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  • Climate change is coming to a place near you « RealClimate
    weather extremes over that period A harder problem but you guys wouldn t be climate scientists if you shied away from hard problems And the answer translates to project costs which we all understand And believe me those backing the investments will be very interested in the answer maybe enough to support some well targeted research projects Anyway it is always good to communicate your position in the other persons language And dollar cost impact is as close to a universal language as we are likely to get Chuck Preble 11 zebra says 8 Oct 2015 at 6 46 AM This could almost be summed up in a simple mantra All climate change is local All mitigation is local All adaptation is local Wish I had thought of this sooner But snark aside I want to agree with t marvell at 8 If you are a gardener or farmer or outdoors person and you still deny something is going on you must really be blinded by ideology 12 Jim Baird says 8 Oct 2015 at 7 21 AM Move the heat into the oceans sweep it under the rug The alternative is 369 trillion dollars in economic costs over the next 200 years and 250 000 additional deaths every year IMHO a little planetary housekeeping is more than justified 13 Victor says 8 Oct 2015 at 10 58 AM As global temperatures rise then we can expect all sorts of related effects from the earlier than normal appearance of deer ticks to rising algal blooms to an increased rise in sea levels and increased incidence of heat waves Also some positive effects such as longer growing seasons The question remains does most of this warming have an essentially anthropogenic cause When we examine the record we see a steep temperature rise from the late 70 s to ca 1998 followed by a leveling off from that year to now The extent and significance of this hiatus has been disputed but I don t think anyone is claiming Earth s temperatures have risen during the 21st century at anything close to the earlier rate But as a result of this earlier rise the Earth is now considerably warmer than it was around 100 years ago When we examine the evidence for the 20th century as a whole we find another equally steep rise taking place between ca 1910 and ca 1941 after that we see a steep decline lasting through most of the 40s followed by a leveling off until the late 70 s Was that earlier rise due to the burning of fossil fuels Since CO2 emissions increased steeply after the 1950s and were relatively modest prior to then such an explanation seems doubtful Moreover if the earlier rise was caused by increasing CO emissions then why was the trend reversed during the 1940s and for almost 40 years thereafter When we examine the evidence from 1910 to the present we see that the enhanced temperatures we are now experiencing are the product of both the earlier and later 20th century rises the later one building on the earlier If we knew what caused both the earlier increase and the decrease following that then we would be in a better position to assess the possibility of an anthropogenic cause 14 Victor says 8 Oct 2015 at 11 27 AM It s a huge leap to go from an increase in deer tick activity and agal blooms to the dire warnings we ve been getting both here and elsewhere projecting catastrophic increases in the rate and intensity of droughts storms and sea levels In the September open thread I cited studies from legitimate scientific sources reporting that neither the incidence nor severity of droughts hurricanes or tornadoes has increased to any significant degree for any appreciable length of time despite the significant runup in temperatures during the previous century See posts 222 229 31 As for sea level that s been increasing for well over a century long before CO2 emissions exploded and will continue to increase even if all use of fossil fuels were to cease tomorrow Thus sooner or later parts of Florida California the Gulf region and many other coastal areas some now heavily populated will be under water This is inevitable there is no way we can prevent it If we spend our money wisely we can take steps to adapt If on the other hand we spend trillions in a futile attempt to roll back the inevitable we ll be impoverished and helpless when the tides overwhelm us You pays your money and you takes your choice 15 A G Gelbert says 8 Oct 2015 at 5 37 PM According to the recently published Hansen et al 2015 study which models of our future using the Eemian period about 125 000 years ago due to certain similarities with our period excluding the fact that the PPM of CO2 was only about 290 back then the oceans are going to get extremely stormy Besides the large increase in sea level the wave action predicted makes every hull design of modern shipping inadequate It will be very hard to sustain our level of civilization without the benefits of modern shipping Redesigning hulls will not work for the simple reason that the waves now called rogue waves of those oceans will be routine 30 to 35 meter tall waves exert forces on a hull of about 100 tons per square meter No modern hull design exceeds 20 tons per square meter This is a serious issue that should be addressed more by the scientific community Actuaries of insurance companies are already addressing it every year on average more than two dozen large ships sink or otherwise go missing taking their crews along with them http www actuarialeye com 2014 03 30 how many ships disappear each year I am grateful to Paul Beckwith of the University of Ottawa for alerting me to the threat from violent oceans that mankind faces Paul Beckwith is a part time professor at the University of Ottawa and a post graduate studying and researching abrupt climate change with a focus on the arctic Part 4 An Ocean Full of 30 meter Tall Waves by Paul Beckwith Published on Jul 23 2015 Near the end of the previous warm period Late Eemian when the sea level was 5 to 9 meters higher than today persistent long period long wavelength waves 30 meters high battered the Bahamas coastline Will we see these massive storm generated waves soon No ship could survive this https youtu be rq24d3 bIU4 16 Dan H says 9 Oct 2015 at 11 32 AM Victor Agreed The ncdc shows a decrease in tornadic activity over the past half century https www ncdc noaa gov climate information extreme events us tornado climatology trends According to Ryan Maue tropical cyclonic activity shows a better correlation with ENSO activity than global temperatures http weatheradvance com home weather weatheradvance com wp content uploads 2014 04 Global Hurricane ACE ENSO PDO 1024 515 png Droughts do not appear to have changed appreciably either http www nature com nature journal v491 n7424 full 491338a html http www3 epa gov climatechange science indicators weather climate drought html http onlinelibrary wiley com doi 10 1002 2015EA000100 full 17 Kevin McKinney says 9 Oct 2015 at 1 42 PM neither the incidence nor severity of droughts hurricanes or tornadoes has increased to any significant degree See more at http www realclimate org index php archives 2015 10 climate change is coming to a place near you comment page 1 comment 636420 Some do say that about drought Others disagree AR5 said the picture was uncertain But note that it s not haven t increased it s can t be shown to have increased And in fact although the statistics are still muddled there are good physical reasons to expect increasing problems with drought chiefly hot weather makes everything drought related worse See California 2015 As to hurricanes I think there is a significant exception the North Atlantic basin shows a long term increase http www nhc noaa gov climo images Atlantic Storm Count jpg But it s early innings for hurricanes yet the projections I ve seen are over century time scales i e keyed to 2100 Simulation experiments show fewer but more powerful cyclones We ll see But there is reason for concern other than the dreaded extrapolation from deer tick data For tornados there s never been any claim that they will increase in a warming climate though research is ongoing due to the persistent suspicion that even though they are small scale storms and therefore hard to simulate tornados should logically get stronger given more thermal fuel Maybe at some point they will get a handle on that As for sea level that s been increasing for well over a century long before CO2 emissions exploded and will continue to increase even if all use of fossil fuels were to cease tomorrow Thus sooner or later parts of Florida California the Gulf region and many other coastal areas some now heavily populated will be under water This is inevitable there is no way we can prevent it I really admire the smooth manner in which you tacitly exclude the possibility that we can still have a significant influence on the ultimate amount and rate of sea level rise But it s still meretricious If governments achieve drastic emissions cuts from 2020 onward RCP2 6 sea levels are projected to rise by between 26 and 54 cm on 1986 2005 levels by the end of the century The average within that range shown as a line through the middle of the left hand grey box is 40cm Under scenarios where emissions stabilise by the end of the century RCP4 5 or soon after RCP6 0 sea levels are projected to rise by between 32 and 62 cm 47cm on average Under a scenario where emissions continue to rise rapidly RCP8 5 sea levels are projected to rise by between 45 and 82 cm or 62cm on average To sum that up even just the mean difference never mind the total span of the estimates has serious emissions cuts holding SLR by 2100 to just two thirds of what it would be under the most drastic emissions scenario Which sadly is the best match for the current carbon trajectory http www carbonbrief org blog 2013 10 what the new ipcc report says about sea level rise 18 s e says 9 Oct 2015 at 2 31 PM Thanks for this article Very important subject but it seems to me often not being considered as a real problem Example my impression as a health care worker and researcher in Norway is that the question what will the consequences of climate change be for health care in the long run is not posed in a serious way The problem does not really exist There is no planning for a different future A report is made there will be some problem with more ticks and a few other nuisances but nobody really cares Everything will go on as before only a little better We will have more money to throw at any problem We will treat more people The services will be even better I have struggled with climate change since woken up by James Hansen s book Storms of my grandchildren but still can t REALLY wrap my head around the catastrophic things that might happen And I read about these things every day Most people don t It s just an unpleasant story not real How does it become real When it hits you Like the war in Syria not really a problem until thousands of refugees cross our borders Then something must be done But with climate change then it s too late 19 Matthew R Marler says 9 Oct 2015 at 2 37 PM Won t most localities continue to experience wide fluctuations in the future very much like those documentable over the past 135 200 years Mean rainfall and mean temp will be higher or in some cases lower but won t the oscillations continue Lots of places are not even prepared for repetitions of past events say the California flooding of 1863 or the recurrent Indus Valley floods or the many ocean storms of the US Eastern Seaboard 20 Lawrence Coleman says 11 Oct 2015 at 7 07 AM 13 Victor umm you might like to tell that to the hundreds of cattle farmers in 80 of Queensland Australia which are as we type experiencing their worse ever drought on record When you ve finished telling the Queensland farmers that there has been no increase in the number of droughts worldwide you just might like to pop over to the other side of the pacific and tell the same crap to all the Californians and generally anyone on the western seaboard of the US Then take a flight to Indonesia etc etc Why are you so blind One agreement I must have with you is that much more money should be spend on adaptation rather than mitigation However this problem is blatantly and unequivocally anthropogenic I doubt for a second that this situation can be reversed now it is already so advanced so adaptation has got to be the only logical way to go 21 zebra says 12 Oct 2015 at 8 20 AM Kevin Mckinney 17 But note that it s not haven t increased it s can t be shown to have increased And in fact although the statistics are still muddled there are good physical reasons to expect increasing problems with drought chiefly hot weather makes everything drought related worse This is the problem with continuing to defend against claims that nothing is going on based on global averages 1 The statistics are muddled and drought can t be shown to have increased 2 There are good physical reasons to expect increasing problems with drought If I locally experience increased problems with drought why is 2 not sufficient for me to rationally even if not with absolute confidence attribute the effect to the cause Are we forgetting Ockham somehow In all these interchanges there is still this strange implication that maybe the physics is wrong Maybe the system isn t acquiring excess energy Maybe the excess energy will not have an effect I know that there have been papers demonstrating what you say about temps affecting the severity of e g the California drought So what is left to demonstrate Why is it necessary to give credence to the kinds of implications contained in comments such as Victor s It has always seemed to me that the bad effects must show up locally before they manifest globally If anyone would like to correct that perception I would really like to hear an explanation 22 Barton Paul Levenson says 12 Oct 2015 at 10 54 AM DH 16 Droughts do not appear to have changed appreciably either BPL Look again http www ajournal co uk pdfs BSvolume13 1 BSVol 13 20 1 20Article 202 pdf 23 Racetrack Playa says 12 Oct 2015 at 10 56 AM Victor studies repeatedly show that dry areas are getting drier and wet areas are getting wetter accounting for the increased incidence of extreme flooding events as well as severe drought events Yes if you average the droughts and floods together you get little average change but that s little consolation for the affected regions Try summing the economic costs of the extreme flood and severe droughts instead A more useful metric isn t it So How does this bimodal response take place Why do some regions get wetter some drier A primary global response to increased atmospheric CO2 is an increase in atmospheric water vapor on the order of 6 7 per 1C of warming In some regions the result is high precipitation North Carolina s flooding was enhanced by atmospheric water vapor fed in from the warming tropics in others the result is drier conditions due to changing atmospheric circulation patterns as well as higher land temperatures that reduce soil moisture Now it may appear counterintuitive for increased water vapor to cause droughts as well as floods but here is where regional conditions become important Desert air 30N S is actually twice as moist as subpolar air 50N S so desert air is not really dry but since the air is too warm for condensation the saturation vapor pressure is too high the water vapor over deserts acts only as an invisible greenhouse gas In contrast in the southern United States that water vapor encounters cold subpolar air lowering the saturation vapor pressure and thus serves as a source of enhanced precipitation leading to record breaking massive flooding Hence drier regions tend to get drier and wetter regions wetter with the driving force being the increase in atmospheric water vapor And this is documented From 1950 to 2002 precipitation increases over Argentina the southern United States and most of western Australia resulted in wetter conditions i e higher PDSI in these regions However most of Eurasia Africa Canada Alaska and eastern Australia became drier from 1950 to 2002 partly because of large surface warming since 1950 over these regions Since 1972 the very dry or wet areas have increased from 20 to 38 of the total land areas with surface warming as the primary cause after the middle 1980s During the last two three decades there was a tendency of more extreme either very dry or very wet conditions over many regions including the United States Europe east Asia southern Africa and the Sahel Dai et al 2004 A Global Dataset of Palmer Drought Severity Index for 1870 2002 24 Victor says 12 Oct 2015 at 12 47 PM 20 Lawrence Coleman Lawrence if you consult this web site http www jaconline com au downloads sose 2004 11 drought pdf you ll see a diagram vertical graph on right illustrating the incidence of major droughts in Australia since 1850 I count 13 and they are fairly evenly spaced I don t see any tendency for droughts to have increased in either frequency or length during this period Much of Australia is desert country anyhow It s the driest continent on Earth by a long shot While it s easy to understand why Australians would be fed up with the current drought I think most of the old timers realize that this is nothing new If the latest has set some sort of record that might relate to global warming if there were some sort of trend toward more and or longer droughts over the last 100 years or so but there is no sign of that either in Australia or the world at large as the report I cited indicates If in fact there has been no trend in the direction of more or longer droughts over the last 100 years then there is no basis for a correlation with either the runup in global warming or the increase in CO2 emissions during that period No one is claiming the world isn t significantly warmer now than it was 100 years ago And one might expect that the increase in warming would lead to a worsening in drought conditions But that does not seem to have been the case And if the warming over the last 100 years hasn t made things worse it s hard to understand how anyone could predict a worsening over the next 100 years 25 Victor says 12 Oct 2015 at 1 53 PM I posted on this topic a few days ago but my post seems to have gotten lost so I ll give it another try First no one would deny that the world is hotter now than it was 100 years ago And there is good reason to assume that the increases in temperature could be having an effect on things like animal and insect migrations polar bear feeding habits loss of polar sea ice and melting glaciers to name a few examples However animal and insect migration patterns and feeding habits have changed many times in the past as have sea ice levels and glacier conditions None of this is really new The question at the present time is given that the current runup in warming is causing the changes we now see then what could be the cause of this runup If in fact the runup in temperatures is caused by CO2 emissions mostly due to the burning of fossil fuels we would expect first of all to see a clear correlation between the increase in atmospheric CO2 and the increase in warming and second of all since correlation does not imply causation we would need to establish that the increased CO2 emissions are the most likely cause of the correlation we see When we examine the history of global temperatures since 1900 however a pattern presents itself that is very far from the clear correlation we would expect Thus regardless of the argument from physics that CO2 has the potential to significantly warm the atmosphere given certain feedbacks that are themselves subject to debate the first equally important condition does not seem to have been met How do I know this From roughly 1910 through 1941 a period of 31 years an increase in global temperature occurred that was at least as extreme as the one observed during the last 20 years of that century Yet the output of fossil fuel generated CO2 during the earlier period was far less than the dramatic runup in CO2 emission during the latter part of the century Since the burning of fossil fuels is unlikely to have been the cause what was Then during the 1940 s there was a dramatic downturn in global temperatures followed by a leveling off until ca 1979 when another significant runup in temps occurred lasting till 1998 Thus from 1941 through 1979 a period of 38 years we see little to no sign of any significant warming So Even if we disregard the period of the so called hiatus from 1998 to present which is admittedly controversial it is impossible to see much sign of any consistent correlation between CO2 emissions and global warming over the entire period when the Earth heated up to the extent we see today What we do see is two periods of extreme warming from 1910 1941 and 1979 1998 with a 38 year period between them in which temperatures essentially leveled off It would seem that the reason the world is so much warmer now than it was 100 years ago is therefore not due to a steady increase in CO2 emissions but to two separate and very possibly unrelated periods of warming in which the later built upon the earlier If the increase in CO2 emissions over the last century were the cause then we would expect to see a concomitant rise in temperatures during the entire period but we don t Now I ve read studies purporting to explain away this discrepancy usually by examining the effects of various forcings during the period in question However the existence of possible ameliorating factors that might appear to save a discredited theory does not in itself demonstrate the correctness of that theory The best such studies can do is suggest possible reasons why the theory appears to fail The claim therefore that studies of this kind are sufficient to prove beyond all possible doubt that the theory is correct after all despite the obvious lack of a clear correlation seems dubious in the extreme 26 Kevin McKinney says 12 Oct 2015 at 2 45 PM Why is it necessary to give credence to the kinds of implications contained in comments such as Victor s See more at http www realclimate org index php archives 2015 10 climate change is coming to a place near you comment page 1 comment 636552 I don t think that contradicting them with clear reasons as to why they are wrong constitutes giving credence 27 Kevin McKinney says 12 Oct 2015 at 2 51 PM 25 Victor you ve said this all before And you ve had the appropriate response before which is that there has always been natural variability in the system and adding an anthropogenic signal won t make that go away You ll still have natural ups and downs but they will be superimposed upon that anthropogenic trend Which would look a whole lot like the observational record http www ncdc noaa gov cag time series global globe land ocean 12 12 1880 2015 Perhaps you find that difficult to see But that doesn t mean that the problem is an objective one 28 MartinJB says 12 Oct 2015 at 3 53 PM Oh Victor If you don t get it yet you probably never will But what the hell one more time for posterity s sake Physics tells us that increasing CO2 concentrations will increase the heat stored in Earth system There is no dispute here In addition physics tells us that other factors also have an impact on the storage of heat in the systems for instance compounds in the atmosphere reflecting light back into space or the distribution of heat within the system for instance oceanic atmospheric interactions causing more heat to be stored in the deeper ocean Again this is nothing controversial At times those other factors will overwhelm the signal from CO2 As a result you should not expect to see a monotonic increase of surface temperature with increasing CO2 at all time scales and periods You could even see a decrease in surface temperature This is all well corroborated by the physical evidence both current and paleontologic Your citation of the recent temperature record as a suggestion that the prediction of AGW is dubious in the extreme displays either ignorance of the facts or a profound lack of understanding about how physical science works The facts have been explained to you many times so I can only conclude that you just can t or wont understand 29 Dan says 12 Oct 2015 at 4 47 PM Now I ve read studies purporting to explain away this discrepancy See more at http www realclimate org index php archives 2015 10 climate change is coming to a place near you comment page 1 comment 636552 Then you have utterly failed to read the peer reviewed science contained referenced in the IPCC reports There is no excuse for such continued scientific intellectual ignorance when it has been clearly demonstrated to you that warming and cooling has occurred over millennia due to natural causes forcings The warming since the 1970s can not be explained by natural causes It can only be explained when the additional forcing from man made greenhouse gases are considered This has been known for a long time yet you continue to show you make absolutely no effort at all to learn but rather lazily regurgitate what you want to believe to heck with the science Busted sport 30 Barton Paul Levenson says 12 Oct 2015 at 5 19 PM V 24 If the latest has set some sort of record that might relate to global warming if there were some sort of trend toward more and or longer droughts over the last 100 years or so but there is no sign of that either in Australia or the world at large as the report I cited indicates BPL As many times as you repeat this I will repeat THIS http www ajournal co uk pdfs BSvolume13 1 BSVol 13 20 1 20Article 202 pdf 31 Barton Paul Levenson says 12 Oct 2015 at 5 21 PM V 25 If in fact the runup in temperatures is caused by CO2 emissions mostly due to the burning of fossil fuels we would expect first of all to see a clear correlation between the increase in atmospheric CO2 and the increase in warming and second of all since correlation does not imply causation we would need to establish that the increased CO2 emissions are the most likely cause of the correlation we see When we examine the history of global temperatures since 1900 however a pattern presents itself that is very far from the clear correlation we would expect BPL Crap CO2 accounts for 82 of the variance of Hadley CRU annual temperature anomalies from 1850 to 2014 That is what anyone in their right mind with some education in statistics would call a clear correlation p 10 40 And it still works if you correct for autocorrelated residuals 32 t marvell says 12 Oct 2015 at 9 30 PM Victor 25 you say that there is a lack of correlation between temperature and CO2 You do that by eye balling the trends finding short term anomalies If you talk about and demand correlation then you should use correlation analysis and not cherry pick elements of the trends In fact the two series are cointegrated the strongest evidence possible of a correlation 33 nigelj says 12 Oct 2015 at 9 43 PM Victor basically claims that correlation is only approximate for CO2 and temperature and sea level rise therefore causation by fossil fuels isn t proven This ignores the fact that in a complex system like climate natural variation makes all correlations rough By analogy its like lung cancer We have only got approximate correlation between tobacco smoking and cancer and a reasonable understanding of causation However the medical community accept smoking causes cancer There are many similar examples 34 Racetrack Playa says 12 Oct 2015 at 9 54 PM Victor are you going to deny that a 1C increase in average surface temperature results in a 6 7 increase in atmospheric water vapor content 35 Richard Caldwell says 13 Oct 2015 at 2 32 AM Victor Also some positive effects such as longer growing seasons RC Wider but perhaps with a month or two hacked out of the middle as too hot and or dry Our geneticists will be very busy Victor I don t think anyone is claiming Earth s temperatures have risen during the 21st century at anything close to the earlier rate RC Pretty much everybody in climate science claims that as a whole the Earth s warming has continued relentlessly What they don t claim is that the teensy part of the Earth we call the bottommost six feet of the atmosphere warmed terribly much between 1998 and 2013 Of course 2015 s first nine months have been rather hot Trends trump weather Victor If we knew what caused both the earlier increase and the decrease following that then we would be in a better position to assess the possibility of an anthropogenic cause RC Dude that s deliberate ignorance Not a pretty debating technique As always there s more detail to learn but climate scientists successfully run models through simulations of the 20th century https www skepticalscience com global cooling mid 20th century advanced htm Victor neither the incidence nor severity of droughts hurricanes or tornadoes has increased to any significant degree for any appreciable length of time despite the significant runup in temperatures during the previous century DH 16 Droughts do not appear to have changed appreciably either BPL Look again Kevin McKinney AR5 said the picture was uncertain But note that it s not haven t increased it s can t be shown to have increased hot weather makes everything drought related worse RC I m with Kevin I m particularly bothered by the possibility of widespread spring flooding followed by baked summer ground which makes next spring s flood not soak in The two can feed on each other so even if the drought index doesn t increase much for human utility things could get grim Susan Anderson algal blooms are on the rise RC And the worldwide coral bleaching which now is a regular part of El Nino The least heat tollerant 10 20 of the world s corals will probably die in the current one Hawaii Great Barrier reef Caribbean If we re lucky warm tollerant corals will rebuild Lawrence Coleman I doubt for a second that this situation can be reversed now it is already so advanced so adaptation has got to be the only logical way to go RC Though the 2degree C limit makes it sound binary climate change isn t a light switch If you had the choice of either a 220 pound man or a 200 pound man of equal abilities hit you you d pick lighter Every ton not emitted drops the damage a tad Victor Much of Australia is desert country anyhow It s the driest continent on Earth by a long shot RC Antarctica 36 Lawrence Coleman says 13 Oct 2015 at 2 41 AM 26 Kevin yeah good point move on 37 Lawrence Coleman says 13 Oct 2015 at 2 53 AM I ve been conducting an experiment Whenever the jetstream over the US at around 250mb becomes appreciably rossby like no clear path meandering all over the place deep excursions from north to south forming many eddies and fractured troughs etc I ve predicted an extreme weather event the next day it gets reported here by our media 2 days later Whether it was flash flooding in UTAH or South Carolina etc I ve been spot on 4 5 times sequentially The obvious slowdown in the jetstream seems to greatly affect the incidence and severity of flash flooding events more than anything else Has anyone else noticed this 38 zebra says 13 Oct 2015 at 7 39 AM Kevin McKinney 26 Let me try to frame this in a more concrete way We often in frustration ask people like Victor OK just tell me what would it take to convince you that CO2 is having an effect Rhetorical of course because we know almost certainly nothing will But let me turn the tables and ask the various people here trying to communicate with and educate the public What would it take to get you to say this flooding in SC was caused by anthropogenic CO2 I mean if it happens two more times in the next ten years would that be enough What about an event with say 50 more rainfall than this one Is there anything short of a complete time series into 2115 that will get us past this point Would even that be enough In my universe if I am convinced that the climate is being changed then any event is by definition a result of that change What am I missing 39 Mark Conder says 13 Oct 2015 at 9 55 AM 16 Dan H wrote Victor Agreed The ncdc shows a decrease in tornadic activity over the past half century https www ncdc noaa gov climate information extreme events us tornado climatology trends Attempting to make any conclusions on the trend of tornadic activity in the U S using the U S tornado database is problematic at best and trying to use it to make any conclusions about the impacts of global warming is beyond ludicrous First the U S is pretty much the only country were such detailed if flawed tornado records are kept Many parts of the world e g Australia portions of Europe and Russia India South Africa etc experience significant tornado activity for which records are much less robust Secondly even the U S database has severe issues with detecting recording and assessing the strength of tornadoes A good starting reference for this is Brooks H E 2013 Severe thunderstorms and climate change Atmos Res 123 129 138 doi 10 1016 j atmosres 2012 04 002 40 Dan H says 13 Oct 2015 at 10 33 AM Racetrack and BPL The 2004 paper to which you refer

    Original URL path: http://www.realclimate.org/index.php/archives/2015/10/climate-change-is-coming-to-a-place-near-you/ (2016-02-13)
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  • A hypothesis about the cold winter in eastern North America + Update « RealClimate
    partial recovery after 1990 discussed further below This recovery is consistent with the finding of an AMOC increase since 1993 based on floats and satellite altimeter data19 Reference 19 is to the Willis data I would suggest that before coming here and accusing scientists of something you should check the basic facts first stefan 2 climatehawk1 says 30 Mar 2015 at 9 29 AM One very modest step that can be taken on this post and all other scientific writings in order to help educate interested readers always first give the full name of something and its acronym in parentheses following prior to using the acronym alone e g Atlantic Meridional Overturning Circulation AMOC This is something that new reporters are trained to do because all readers are assumed to be newbies and it would be an excellent discipline for scientific communicators as well Response Thanks good point I ve added a glossary at the bottom 3 Fergus brown says 30 Mar 2015 at 10 56 AM By coincidence the UK is downstream of the North Atlantic cold spot yet we are still seeing above average temperatures note though the cold Winters of 2010 11 probably linked to a THC slowdown which on the surface seems to repeat the pattern you suggest 4 Jim Eager says 30 Mar 2015 at 11 08 AM Carl don t need no stinking facts 5 Chuck Larlham says 30 Mar 2015 at 11 14 AM And you ve just perfectly demonstrated the problem the climatology scientists have Your jargon is unintelligible nor could most of them do any better with the biological jargon in which my research work was soaked and the general public can t read either of them Too much prior understanding is assumed I for instance having read the first part three times I m almost ready to start diagramming sentences still do not understand why you reversed the signs in the warming cooling gyres at least I know what a gyre is Granted I hold only a Master of Science in Ecology and Environmental Science from USU s School of Wildlife Biology but I am nonetheless a scientist and I am made to feel utterly ignorant Now if I become frustrated enough I can dig this stuff apart and figure out the details or I can say Well I trust the methodology used by competent scientists which is my more likely response And I have valid reason for that Unfortunately the general public and that includes the lawyers who make up the vast majority of our State and federal Representatives and Senators does not They just get lost in this stuff Response Agreed this post was written too quickly as a follow up and assumed prior knowledge of the key terms from my previous post Btw you don t need to understand why in some cases the temperature pattern is plotted for an increase and in some cases for a decrease in the AMOC as long as you get the point that the colours in some plots are just the other way round although they show the same thing stefan 6 Durou says 30 Mar 2015 at 11 25 AM This more recent research on the AMOC suggests it is still declining but not as the climate models suggest http www ocean sci net 10 29 2014 os 10 29 2014 pdf 7 SecularAnimist says 30 Mar 2015 at 12 49 PM Well doc based on this diagnosis what is the prognosis 8 Kevin McKinney says 30 Mar 2015 at 1 10 PM 1 and response Ah but to a denialist real data is data that kinda sorta somehow supports the argument that he happens to be making at the moment at least if you look at it squinch eyed in the exactly the right light 9 Racetrack Playa says 30 Mar 2015 at 2 04 PM I m a bit confused could the current east Pacific SST anomalies also be playing a contributing role or is that included in the above analysis http www nhc noaa gov aboutsst shtml The role of Pacific SSTs could be something like this the large body of warm water along the North American west coast must be dumping more moisture into the atmosphere this moisture is carried by the jet stream northwards hence not ending up falling out as snow over the Sierra Nevada Cascade Range etc over Canada where it encounters cold dry subpolar air sweeping down from the Arctic hence what you have in this configuration is record snowfalls and cold snaps across the eastern United States This is interesting in that some scientists are now saying that a reduced average equator to pole temperature gradient will mean less extreme weather not more but that argument seems to ignore seasonality i e while average temperature gradients may decrease the seasonal transitions would become more abrupt due to masses of warm wet tropical air mixing with breakouts of cold dry arctic air Here s the press release for that claim out of Zurich and Caltech http www sciencedaily com releases 2015 03 150327132207 htm The study s point of departure was that higher latitudes are indeed warming faster than lower ones which means that the temperature difference between the equator and the poles is decreasing Imagine for a moment that this temperature difference no longer exists This would mean that air masses would have the same temperature regardless of whether they flow from the south or north This report seems a bit iffy due to the seasonal temperature changes brought on by the tilt of Earth s axis 10 Carl says 30 Mar 2015 at 2 30 PM You should perhaps check with Norwegian oceanographers http www nrk no verden golfstraumen har ikkje endra seg 1 12287209 Response But that article first wrongly claims that the Willis data contradict our results as you did and then secondly discusses thermohaline flows to the north of the cold patch we discuss namely the exchange with the Nordic Seas which according to our Fig 2 does not correlate at all with that cold patch south of Greenland and about which we have accordingly made no claims whatsoever No inconsistency with our paper there stefan 11 Robert says 30 Mar 2015 at 3 29 PM Interesting essay As I look at Fig 1 I see a pattern that seems reminiscent of the winter of 2013 2014 colder than average along the eastern part of the U S and warm and dry on the west coast with above normal SST for eastern Pacific and western Atlantic I don t recall seeing a figure like Fig 1 for last winter Dec 2013 Feb 2014 Would be interesting to compare the two if available You mention last winter and refer to Fig 5 but the two images in Fig 5 are labeled Dec 12 2014 and Feb 11 2015 which I interpret as being for the winter we just had i e this winter we still have snow on the ground here in the Boston area and in fact seems to be within the same time frame as your Fig 1 Is that what you meant by last winter But perhaps I m reading it wrong wouldn t be the first time In any case I m wondering if this pattern is the new normal If so should we in the Boston area expect another interesting winter next year And what is the future of California agriculture if this is the new normal Or as SecularAnimist asked comment 7 what is the prognosis 12 Thomas says 30 Mar 2015 at 8 34 PM Is the West coast warm anomaly the right number actually fractional of Rossby wavelength away from the dipole that it serves to strengthen weaken the effect of global circulation If this hypothesis works out to be true what does it say about the extreme dryness heat we ve been having on the west coast 13 patrick says 31 Mar 2015 at 12 00 AM Chuck Larlham I sympathize and I disagree It s a pleasure and a great lesson to find someone who isn t afraid to think out loud in public This kind of leadership is rare and valuable If the person is a substantial thinker then it s all the more so The contributors and guest post authors on this site can be found on Facebook Twitter and any number of science culture and news sites as well as in the books textbooks and research they have authored Citizen scientist his term Peter Sinclair is a good example of another kind He s the public too and he got it 14 patrick says 31 Mar 2015 at 12 25 AM Durou 30 Mar 2015 at 11 25 AM Thanks for the document This research is reference 28 on the new study by Rahmstorf et al which is the topic of the previous post by Stefan http www nature com nclimate journal vaop ncurrent full nclimate2554 html Context from UK National Oceanography Centre of the Natural Environment Research Council on the reference you cite http noc ac uk news ten years ocean monitoring uncovers secrets changing uk winters 15 patrick says 31 Mar 2015 at 12 48 AM Durou 30 Mar 2015 at 11 25 AM Thanks for the document It Smeed et al 2014 is the 28 reference on the new study by Rahmstorf et al which is the topic of the previous post http www nature com nclimate journal vaop ncurrent full nclimate2554 html Context from UK National Oceanography Centre of the Natural Environment Research Council on the reference you cite http noc ac uk news ten years ocean monitoring uncovers secrets changing uk winters 16 Martin Smith says 31 Mar 2015 at 2 35 AM When the AMOC runs at it s normal speed the heat off the US east coast would be carried to the cold spot to cancel it out 17 zebra says 31 Mar 2015 at 6 34 AM Following up my comment in the previous thread for which this is a perfect example I am not asking for a prognosis as SecularAnimist and robert are but rather what would you need to give a confident relatively definitive prognosis for this regional effect How or when would the characterization of a new normal for Eastern USA become part of the science if there were to be such a characterization Is there any new methodology in the works that can get us beyond just waiting for the time series to fill in 18 Eric Swanson says 31 Mar 2015 at 10 26 AM Racetrack Playa 9 I m always a bit leery about sweeping claims based on simple models The study you point to uses a model described thusly We test the validity of the theoretical arguments and changes in the PDF of near surface potential temperatures more quantitatively in simulations with an idealized GCM which has a hydrologic cycle an entirely water covered surface and a simple representation of ocean heat transport in low latitudes A Water World with no sea ice and no land with orographic effects and different albedos or seasonality What good is that Of course the report goes much further comparing their results with those from 8 models taken from the Coupled Model Intercomparison Project CMIP5 RCP8 5 simulation experiments There s quite a bit to digest from their effort but the basic assumption is that the CMIP5 results are a valid projection for the future so it s just another brick in the wall IMHO 19 Frank says 31 Mar 2015 at 10 40 AM The pattern is indeed a strong hint for a weakening of the AMOC as observed since 2004 and very strong during 2014 see SSTspg When one compares the correlation of the SSTspg http www directupload net file d 3943 dn63d7xe jpg htm via CE with GISShttp data giss nasa gov tmp gistemp NMAPS tmp GHCN GISS ERSST 1200km Anom1203 2015 2015 2000 2007 nmaps gif as the deviation from the early years of the century there could be a clear connection of the pattern to the impact of a strong weakening of the AMOC 20 Jai Mitchell says 31 Mar 2015 at 10 54 AM I am surprised that your line of inquiry did not address the nearly zero ocean heat accumulation in the northern hemisphere during the ARGO buoy period with ALL OHC accumulation in the south This is a stark declaration of the dimming of northern hemisphere sun by anthro aerosols This effect works to temporarily increase the rate of the AMOC masking the effects of recent glacial melt as well as helps establish the West Pacific Ridiculously Resilient Ridge blocking pattern which funneled the aerosol stream north into the Yukon and then into a standing wave pattern through the Eastern U S and up into the North Atlantic 21 vukcevic says 31 Mar 2015 at 5 00 PM Slowing or speeding of sub polar gyre makes very little difference a single cycle takes anything up to 20 years What matters is the feedback driven oscillation between the SST and westerly winds further north two down welling areas surprisingly but for a good reason the Nordic Seas summer s down welling is the dominant influence on the SST multi decadal oscillations 22 Hank Roberts says 31 Mar 2015 at 6 48 PM The cold spot is fresher water and equally cold but saltier water would sink allowing the surface warmer salty water to move into that area I m asking I m not at all sure of the time sequence over say a decade here with changes in temperature and salinity of parcels of water I found Nature 457 711 714 5 February 2009 doi 10 1038 nature07717 Received 17 March 2008 Accepted 9 December 2008 Holocene oscillations in temperature and salinity of the surface subpolar North Atlantic David J R Thornalley1 Harry Elderfield1 I Nick McCave Model studies predict a weakening of AMOC in response to enhanced Arctic freshwater fluxes4 although the inflow can compensate on decadal timescales by becoming more saline5 Our data suggest that such a negative feedback mechanism may have operated during past intervals of climate change 23 S Molnar says 31 Mar 2015 at 7 17 PM I also have to disagree with Chuck Larlham and by extension with Stefan himself I guess Stefan referenced his previous post at the top of the current post so anyone paying attention and a fotiori any scientist should have read that post before complaining about jargon in the current post Is the sum of the two posts still a problem Well it isn t for me and I m not a scientist at all I suppose it s possible that there s something undefined that an educated reader could not be expected to understand but I don t see it As for the sign reversals in the temperature patterns well that s pretty basic stuff I think even my 10 year old would get it but I haven t done the experiment yet so I m not certain 24 Eric Swanson says 31 Mar 2015 at 8 45 PM Hank Roberts 20 Here s a link to another interesting paper on changes to the subpolar gyre STG at the end of the Eemian associated with the return of Ice Age conditions Oceanographic dynamics and the end of the last interglacial in the subpolar North Atlantic They conclude with this comment This allowed the warm and salty waters from the STG to penetrate to higher latitudes in the northeast Atlantic and into the Nordic seas which in turn contributed to the intensification of northern AMOC during glacial inception as proposed by previous model and data inferences Paradoxically despite the northward heat transport of this inflow the intensified deep overturning at this time may have contributed to the regional and thus global glaciation by providing a moisture source for incipient glaciers 25 Eric Swanson says 31 Mar 2015 at 8 48 PM Hank Roberts 20 Here s a link to another interesting paper on changes to the subpolar gyre STG at the end of the Eemian associated with the return of Ice Age conditions Oceanographic dynamics and the end of the last interglacial in the subpolar North Atlantic They conclude with this comment This allowed the warm and salty waters from the STG to penetrate to higher latitudes in the northeast Atlantic and into the Nordic seas which in turn contributed to the intensification of northern AMOC during glacial inception as proposed by previous model and data inferences Paradoxically despite the northward heat transport of this inflow the intensified deep overturning at this time may have contributed to the regional and thus global glaciation by providing a moisture source for incipient glaciers Something to think about 26 Thomas MH Witt says 1 Apr 2015 at 6 36 AM I feel that too often the wheel is re invented every year Looking at the SST anomaly pattern off the US East Coast here it strongly reminds me on my thesis from about 20 years back in an uncoupled atmospheric GCM study where I compared one decade of a positive SST anomaly to a 100 years climatological reference run of a T42 model with 95 t test The study is in German but the graphics are self explanatory to the expert I got a large literature compilation which you may use as further reference to previous studies kindly quote me http www scribd com doc 231457635 Der Einfluss Nordatlantischer Meeresoberflachentemperaturanomalien SST Anomalien auf die globale Zirkulation der Atmosphare The Impact of North At The impact is purely generated by that pattern of localized positive SST anomaly off the US East Coast The only force in the Control Run of the GCM is the underlying monthly mean global SST The study was fundamental to further as well coupled studies at the time and is more sophisticated than a pure water

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  • What’s going on in the North Atlantic? « RealClimate
    circulation amplified by the presence of the coastline http oceanmotion org html background western boundary currents htm Conceptually it s hard to see how the Gulf Stream western boundary current could be weakened by conditions around Greenland this is a fluid dynamics system not a mechanical belt a backup due to less deep water formation should have little effect on the physics of the gyre and the formation of the western boundary current and it also seems the tropical warming and the resulting equator to pole heat transport are the drivers but perhaps modulation by jet stream meandering is playing some role in the cooling Paleoclimate studies of tropical ice cores tend to support the scenario of changes in the tropics propagating northwards too not the reverse Hence the entire North Atlantic Driven Global Climate Change theory might be in need of revision conditions in the North Atlantic may instead be responding actively to changes in the tropics not the other way around This is a touchy topic for advocates of Broecker s theories but the paleoclimate data collected in the tropics just don t support that scenario There don t seem to be any master switches in the North Atlantic region that can toggle global climate into one state or another Response We are talking about the AMOC here not the western boundary current which indeed is largely wind driven and more specifically about the thermohaline driven part of the AMOC Its variations are controlled by density changes in high latitudes and not from the tropics In paleoclimate I would say it is well established by now that things like the Younger Dryas event or the climatic response to Heinrich events are driven by high latitude buoyancy mainly freshwater forcing Fans of the tropics as climate driver have tried but in my view failed to come up with alternative explanations for these events stefan 16 Thomas O Reilly says 23 Mar 2015 at 10 00 PM Our recent study Rahmstorf et al 2015 attributes this to a weakening of the Gulf Stream System which is apparently unique in the last thousand years this indicates that climate models UNDERESTIMATE the weakening of the Atlantic circulation in response to global warming That this might happen as a result of global warming is discussed in the scientific community since the 1980s It is 2015 now 35 years later What are you and the rest of the Climate Science community going to do about it now Stefan More research More reanalysis Another Paper Another article for Real Climate An AR6 IPPC Report in a few years time Insanity doing the same thing over and over again and expecting different results Albert Einstein Response What is your suggestion what we should do as scientists other than study the system to our best ability and communicate what we find stefan 17 Alec Barken says 23 Mar 2015 at 10 46 PM Apologies for not posting a data or research related question I m a bass player Does this paper scare anyone else like it kinda scares me Again I m not a scientist and maybe not used to clinical detachment but everyone seems so calm Except for Box That dude looks like he has a lot of bad news to deliver Is it not a big deal Is it just that we have no reference for this type of event trend Also I get the whole Day After Tomorrow plot reference attention grab thing but it trivializes the severity of the issue IMo Seems like maybe The Road would be more appropriate That movies plot connection was 1 Humans break the the Oceans acidification check irradiation from subs reactor flush accidents Fukishima check toxification heavy metals from industry oil spills toxic waste dumped at sea plastic gyres check 2 Really bad things happen 18 Chuck Hughes says 24 Mar 2015 at 12 23 AM Does anyone know how to put the toothpaste back in the tube once you ve squeezed too much out I m having trouble understanding how anyone expects to fix this problem Any ideas Thanks 19 Hank Roberts says 24 Mar 2015 at 1 16 AM Wili we know we re f ed The devil is in the details to know those we need good science for choosing to work toward the right changes Time and energy and attention and resources are limited Wasting them is unwise Some of the plans being pushed are scams excuses to make money fast Some are well meaning fantasies Figuring out what s what takes attention Fear is the mind killer Don t waste time Don t echo confusion and fear Deal with it 20 richard pauli says 24 Mar 2015 at 2 34 AM 17 Alec You are quite right it is astounding And I invite you to respect your fear and maybe try to dismiss or move past it Many people hold it in awe and deep admiration for the wondrous complexity of the science The ramifications are beyond all comprehension Nothing in all history of civilization is this momentous And yes the data and news and reports now come faster than ever It is hard to process It s just that many here have been studying related topics via this site for years many years This is the only place on the Internet I know of where great and respected scientists and lay amateurs can continually converge in a civil manner seeking information The very design of this site enables this conference like exchange It was built and evolved for both exchange and as a great reference Sometimes in a crisis it is comforting to do science to explain and dissect and understand It s like in medicine when we get a diagnosis of a cancer one way of dealing with the shock is to dive into the medical science As did the late Dr Stephen Schneider look for his videos for a balanced attitude Everyone I meet is stunned about it but each person processes it at different levels Work helps Learning how to best communicate is vital It seems like everyone respects anticipatory grief Many know it is there and just prefer to keep working on the science It is huge It deserves our full attention It is a huge topic to examine how humans might best process news and science that seems so ruthlessly harsh 21 richard pauli says 24 Mar 2015 at 3 04 AM And Alec there s a great need for a bass player more music The movement and the science needs new anthems operas and marches to inspire and get us moving I found a couple of YouTube playlists that total about 100 pieces of music some are very old and classic Some rock some humor plenty of variety but more music needed https www youtube com watch v qB4UEQzUmWc list PLU5dY2n3AbGHCgJ9OiDxG5hjY9QYAkQ55 https www youtube com playlist list PLaSHX1Y3kE0yqRjnOxIp9fB EmZbkb0qU 22 CM says 24 Mar 2015 at 3 28 AM In the paper you mention that and indeed the time history of Greenland meltwater runoff is not included as a forcing in the CMIP5 ensemble 2nd para before end Is it the precise time history that is the point that is that with natural variability and all models might not be expected to capture the timing of the 1970 1990 cooling Or is the freshwater flux to the ocean from the melting ice sheet for some reason not represented in the models as a forcing on the circulation That s how I first read it but it doesn t rhyme Response Indeed it is the latter most global climate models do not yet include continental ice sheet models stefan 23 Mary Paino says 24 Mar 2015 at 6 12 AM I live on the NH seacoast and have directly observed an ocean that has had a significant decrease in wave height on average wave height has only been 1 3 ft On most days it is very difficult to differentiate between the tide coming in or going out The water rises and lowers but there is very little wave action on the approach of the high tide Also I believe we are seeing the beginning of a new glacial southern migration the Arctic ice cap has thinned and the surface mass has been on the increase which to me is indicative of a glacial formation 24 jyyh says 24 Mar 2015 at 6 59 AM 17 not posting a data or research related question I m a bass player Hi there I knew it Takes a basist to now one Haven t seen The Road so can t comment on that but one single spot of cool on the ocean surface won t stop the warming on the continents for most of the year so The Day After Tomorrow is out Maybe this keeps the winters a bit cooler that s to say normal or only slightly warmer than previously in east coast of North America and European shores of Atlantic Jason Box has really some nasty things to say that I however I would like can t refuse true Ocean is not too large that humans could not influence it Does fish taste different today than twenty years ago I can t say either but maybe 20 years from now 25 Icarus62 says 24 Mar 2015 at 7 10 AM Wasn t this scenario described by James Hansen in his book Storms of My Grandchildren 26 Slioch says 24 Mar 2015 at 7 11 AM What are the long term and how long term consequences of a failure of the Atlantic meridional overturning circulation for i global oceanic circulation and ii ocean anoxia in a warming world There is evidence reported by Peter Ward of purple sulphur bacteria detected via the existence of long lived fingerprint molecules that require oxygen free H2S abundant conditions with sunlight in therefore shallow seas at the end Permian mass extinction and other such events If the Amoc slowdown is the first step towards ocean anoxia it would appear also to be the first step towards utter catastrophe 27 CM says 24 Mar 2015 at 7 31 AM Stefan 22 thanks I had somehow got the idea that ice sheets were included now but I should have checked the AR5 is explicit they re not coupled in CMIP5 My bad 28 Yvan Dutil says 24 Mar 2015 at 7 39 AM Correct me if I am wrong This cold spot is likely to come from the Arctic glacial melting This is not include in climate model Therefore we don t know what will be the global consequence It is my understanding that such cold spot could be the source of the permanent high that bring the Jet Stream south and kept the East of North America cold for the last two years Accordingly this might be a semi permanent climatic feature This semi permanent state might end up when the AMOC will stear its trajectory or slow down to the point that it no longer bring heat into the Artic ocean which may refreazed get colder and stop the Greenland melt I plan to do a blog post on this So any additional information would be interesting 29 Hank Roberts says 24 Mar 2015 at 7 58 AM for Alec A Song of Our Warming Planet Ensia ensia com videos a song of our warming planet Jun 28 2013 What does climate change sound like approach called data sonification to convert global temperature records into a series of musical notes using music to communicate the latest in climate science converts global temperature records into a series of musical notes with the coldest year on record 0 47 C in 1909 set to the lowest note Stay with the base and let s hope there s no call for ukeleles 30 Sven says 24 Mar 2015 at 8 18 AM Any comment on this paper showing there is no slowdown And why is this paper not referenced http onlinelibrary wiley com doi 10 1002 2013GL058636 abstract Abstract In contrast to recent claims of a Gulf Stream slowdown two decades of directly measured velocity across the current show no evidence of a decrease Using a well constrained definition of Gulf Stream width the linear least square fit yields a mean surface layer transport of 1 35 105 m2 s 1 with a 0 13 negative trend per year Assuming geostrophy this corresponds to a mean cross stream sea level difference of 1 17 m with sea level decreasing 0 03 m over the 20 year period This is not significant at the 95 confidence level and it is a factor of 2 4 less than that alleged from accelerated sea level rise along the U S Coast north of Cape Hatteras Part of the disparity can be traced to the spatial complexity of altimetric sea level trends over the same period Response There is many more papers we could have discussed but the journal allows only 50 references to be cited actually we even have 51 due to one citation error that was discovered only at proofs stage The Rossby paper is not that relevant to our paper because it deals with much shorter time scales 20 years of data while we use decadally smoothed data over 1100 years and with the Gulf Stream rather than the AMOC Actually for those 20 years analysed by Rossby our index shows an increase in the AMOC but that is so small that it would be within the uncertainties of Rossby s calculated trend in the Gulf Stream So no inconsistency there stefan 31 Susan Anderson says 24 Mar 2015 at 8 40 AM Mary Paino you may set your fears at rest The record shows quite the opposite For more detailed information you might go to Neven s or for a matter of that any of the more official bodies such as the NSIDC that regularly update their information based on the latest observations http neven1 typepad com blog Politics will not change reality the ever evolving methodology of science which attempts to look at and understand reality is our best bet for knowing the big global picture And the science involved with the effects of accumulating heat trapping greenhouse gases increasing the energy in our earthly circulatory system goes back to Arrhenius and Tyndall and has only become clearer over time http www aip org history climate index htm Of course there are local variations in sea level height as you personally attest for a variety of reasons However you bring forward a deeper problem which is the prevalence of short term and local observation supported by what is sometimes called blog science and the media s acceptance of false balance that provides you with a massive amount of unreliable information some of it very professionally presented using the best PR money can buy from the wealthiest industries on earth with an infrastructure that mimics the real thing and encourages you to reject what is an overwhelming agreement amongst the world s best expertise about what is going on 32 tom says 24 Mar 2015 at 8 55 AM Does this have any link to colder winters in eastern North America I m hoping the answer is no 33 Hank Roberts says 24 Mar 2015 at 8 57 AM So ah this was in 2005 Set in an America of the almost now Fifty Degrees Below and the first volume of the trilogy Forty Signs of Rain tells the story of the efforts of a loosely connected group of scientists campaigners and politicians to provoke a national response to the crisis of global warming Unfortunately for them as environmental aide Charlie Quibbler observes it s easier to destroy the world than to change capitalism even one little bit It is not until the combination of two colliding storm systems and an unprecedented tidal surge causes Washington s Potomac river to bursts its banks and overwhelm the country s capital at the climax of book one that the world sits up and takes notice But by this point the polar ice caps have already begun to melt in earnest shutting down the warm waters of the Gulf Stream Kim Stanley Robinson about the trilogy and the ideas and political circumstances that gave rise to it I read years ago about the possibility of global warming leading to the West Antarctic ice sheet detaching and the level of water displacement that would entail he explains And I started thinking well what would we do Would it be possible to do anything And at that point you get into terraforming and science fiction http www theguardian com books 2005 sep 14 sciencefictionfantasyandhorror sarahcrown I d welcome a topic on what the climate scientists have been reading I recall long ago how Ray Bradbury was given a tour of a NASA facility and was taken completely by surprise when everyone there knew who he was They d grown up on his stories about space travel What are you young climate scientists and your kids growing up reading 34 Leif Knutsen says 24 Mar 2015 at 9 16 AM Capitalism unrestrained by the requirements of Planetary life support systems is guaranteed mutually assured destruction Socially enabled capitalism is clearly a failed paradigm Help end tax funded pollution of the commons for starters We are all leaders family friends community etc followers the thousands of enlighten luminaries throughout history and boots on the ground do what you can every day to make the world a better place We don t have a right to ask whether we re going to succeed or not the only question we have a right to ask is What s the right thing to do What does this Earth require of us if we want to continue to live on it Wendell Berry 35 Thomas O Reilly says 24 Mar 2015 at 10 06

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  • Limiting global warming to 2 °C – why Victor and Kennel are wrong + update « RealClimate
    to address the issue It is not too cynical of me to believe that the usual suspects will read Victor and Kennel s editorial and claim SEE the science is NOT settled I ve been convinced for some time that the science communities effects on actual national policies on this issue have maxed out that we are left with the large body problem of national and international politics which are driven by more basal issues than the fineries of intellectual debates within small circles of academics 5 Alvin Stone says 1 Oct 2014 at 6 02 PM What is the likelihood we have enough energy in the system that we have already blown the 2 degree limit It seems to me this is likely especially if sensitivity is towards the top end of estimates If that is the case what do we do then when 2 degrees no longer has value simply push the next limit up to 3 degrees Perhaps the issue to be explored here is that natural variation has such a large influence on global average temperatures that at the very least we may need to factor in other measures with defined numbers to give governments a clearer idea of where we really are at in terms of the limits on carbon emissions While I disagree with the Nature article I wonder if there is some merit in making other indicators as prominent as the 2 degree limit to highlight the urgency of the climate situation and encourage action 6 BillS says 1 Oct 2014 at 7 45 PM In the mid 1980s as the debate over whether there was a causal link between lung cancer and smoking cigarettes was escalating a tobacco company famously said Our product is doubt and confusion The scientists supporting that product were Victor Kennel s ancestors with similar expertise on the matter at hand One should always ask Cui bono about such opinion pieces 7 Adam Gallon says 2 Oct 2014 at 2 16 AM Where did the 2C limit come from what peer revued papers 8 Chris Vernon says 2 Oct 2014 at 3 28 AM That something is affordable 0 06 of global GDP doesn t show that it is feasible I expect the global population becoming largely vegetarian is hugely affordable even profitable due to the relative inefficiencies of meat production but is isn t going to happen any time soon Whilst it s clearly technically feasible to avoid 2C warming in my opinion it is no longer politically culturally feasible 9 Kevin McKinney says 2 Oct 2014 at 4 38 AM 7 Adam your question about the genesis of the 2 degree limit seems to presuppose a simple answer one in which there are a couple of papers you could look up and be done But let s reread the relevant description from the post above A tolerable temperature window up to 2 C above preindustrial was first proposed as a practical solution in 1995 in a report by the German government s Advisory Council on Global Change WBGU It subsequently became the climate policy guidance of first the German government and then the European Union It was formally adopted by the EU in 2005 Also in 2005 a major scientific conference hosted by the UK government took place in Exeter covered at RealClimate to discuss and describe scientifically what avoiding dangerous climate change means The results were published in a 400 page book by Cambridge University Press Not least there are the IPCC reports as mentioned above and the Copenhagen Climate Science Congress in March 2009 synthesis report available in 8 languages where the 2 C limit was an important issue discussed also in the final plenary with then Danish Prime Minister Anders Fogh Rasmussen Don t give us too many moving targets it is already complex That s mostly about the political deliberations to be sure not the scientific underpinnings of the goal But note the citations the CUP book the relevant Assessment Reports presumably TAR and AR4 and the Copenhagen Synthesis Report of 2009 That s a bunch of reading of course I m presuming that that means that as with so much in the climate change context that there are many many papers on impacts mitigation and adaptation that figured into the debate Frustrating but that may just be how it is 10 Juvamend Review says 2 Oct 2014 at 4 41 AM Hi there just wanted to give you a brief heads up and let you know a few of the images aren t loading correctly I m not sure why but I think its a linking issue I ve tried it in two different browsers and both show the same outcome 11 handjive says 2 Oct 2014 at 5 25 AM Part 8 The Invention of the Two Degree Target A group of German scientists yielding to political pressure invented an easily digestible message in the mid 1990s the two degree target But this is scientific nonsense Two degrees is not a magical limit it s clearly a political goal says Hans Joachim Schellnhuber director of the Potsdam Institute for Climate Impact Research PIK The world will not come to an end right away in the event of stronger warming nor are we definitely saved if warming is not as significant The reality of course is much more complicated Schellnhuber ought to know He is the father of the two degree target Yes I plead guilty he says smiling The idea didn t hurt his career In fact it made him Germany s most influential climatologist Schellnhuber a theoretical physicist became Chancellor Angela Merkel s chief scientific adviser a position any researcher would envy http www spiegel de international world climate catastrophe a superstorm for global warming research a 686697 8 html Response Typical Spiegel stuff a rather imaginative story Of course the 2 C limit is a political choice who else other than elected representatives would have a mandate for a normative choice for climate policy Science can only help to inform this choice i e provide an analysis of the risks that come with different warming levels as thousands of peer reviewed studies and the assessment of this literature by the IPCC do What level of risk society wants to accept and thus what goals are considered appropriate for climate policy is not for scientists to decide It is a decision similar to that about a speed limit on a piece of road which is also a risk assessment that can be informed by scientific data like accident statistics but remains a political decision And of course a limit of 50 km h is not chosen because at 51 km h something terrible happens risks overall increase gradually That even applies in the presence of thresholds like that for marine ice sheet instability because it is not precisely known where they are so that the risk of crossing them gradually increases with more warming stefan 12 James Wimberley says 2 Oct 2014 at 6 40 AM The IPCC s 0 06 reduction on GDP growth rates should be read and should have been prestnted as as zero to well within measurement error Economic indicators are inherently much much more uncertain than physical ones GDP isn t a measurement it s an estimate consult any manual of national income statistics or methods pages of statistics agencies on the numerous judgement choices and corrections that you have to make For instance production GDP NNP and income statistics GNI NNI should match perfectly They never do in practice The discrepancy for the US in 2003 was 23bn or 0 02 Past GDP is routinely corrected with changes an order of magnitude higher than 0 06 Any economist would say that forecasting next year s GDP to within 0 1 is fanciful For 50 years it s a joke 13 Dan H says 2 Oct 2014 at 6 46 AM Adam Good question It appears to have originated with the UNEP advisory group in 1989 when they stated 2ºC increase was determined to be an upper limit beyond which the risks of grave damage to ecosystems and of non linear responses are expected to increase rapidly In 1996 the EU established its 2C policy target to avoid the worst impacts of global climate change The number appears to be more of a convenient choice rather than a strict barrier Indeed some have been quite critical of this choice The 2 deg C limit is talked about by a lot within Europe It is never defined though what it means Is it 2 deg C for the globe or for Europe Also when is was the base against which the 2 deg C is calculated from I know you don t know the answer but I don t either I think it is plucked out of thin air Phil Jones email to Christian Kremer 06Sept2007 Response In the original proposal by WBGU in 1995 in the EU decision of 2005 linked to above to ensure that global average temperature increases do not exceed pre industrial levels by more than 2 C and in the Cancun decision cited above these points are clearly defined Not sure what the point is of citing some old email by someone who simply says he does not know how it is defined stefan 14 PeteB says 2 Oct 2014 at 6 48 AM Climate policy needs a long term global goal I disagree that s one way of doing it The other way is a pigovian tax to price carbon based on the likely harm taking into account the uncertainties and the non linear impacts A Goal isn t needed fossil fuels will only be burnt if they are economically providing more value than harm of course we can ramp up the carbon tax over time to work with the grain of the economic cycle and reduce the economic dislocation so for example existing power stations can be used for the remainder of their useful life but the prospect of a steadily increasing carbon tax rate would make building new fossil fuel power stations uneconomic 15 Arun says 2 Oct 2014 at 6 50 AM Off topic but necessary to say Indian Prime Minister Modi in his visit to the US at the event at Madison Square Garden at the Council for Foreign Relations spoke repeatedly of the crisis that climate change is bringing upon the planet and of his plans for clean energy for India He has the slogan zero defect zero effect for manufacturing in India i e Indian manufacturing will try to be world class and try to have zero net effect on the environment Strange that this has received next to zero coverage in the US media and blogs If you estimate the sustainable rate of carbon dioxide emission so that CO2 concentration remains constant for the planet and divide it by the world population you get a per capita carbon budget tons of CO2 per person per year Response I would say that the sustainable rate of CO2 emission is zero Simplifies the math if not the situation David Two important observations Indians as of 2007 were well below this per capita limit 1250 million Indians want to industrialize and fast that is why they voted for Modi So what India is able to do is crucial to the future of the planet s climate When the Indian Prime Minister Modi comes to the US and talks about climate change and his aspiration to industrialize in a carbon neutral way and the US media collectively gives a yawn it is infinitely and amply clear that climate change is not taken seriously here even in the liberal section of the media When a key player in the world s carbon dioxide economy lands on their shores and talks planet friendly it is a non event Conclusion Climate change doesn t exist for the Republicans and for the Democrats it is merely a way to bash Republicans as anti science 16 James Wimberley says 2 Oct 2014 at 6 52 AM Sorry 25 6 bn Wikipedia 17 jgnfld says 2 Oct 2014 at 7 08 AM 7 Uh did you read the article A summary of the scientific process that led to the 2 degree guideline is pretty clearly given This process included much peer review and discussion 18 SellaTheChemist says 2 Oct 2014 at 8 05 AM The link to Climate Analytics is malformed Response Thanks should work now Stefan 19 Chris Dudley says 2 Oct 2014 at 9 02 AM Sabotage is the correct word I think that we have not considered targets below preindustrial which is a shame Dropping sea level by a couple meters would likely pay for itself in coastal real estate development 20 SecularAnimist says 2 Oct 2014 at 9 43 AM We don t need goals and targets We need to end all fossil fuel use as rapidly as possible period It s very simple 21 Clayton Gearhart says 2 Oct 2014 at 10 25 AM William Nordhaus s new book the title of which triggered a spam warning has a lot to say along these lines that is for the most part consistent with this post 22 ajki says 2 Oct 2014 at 11 03 AM If this piece will be reposted on Klimalounge my clear projection is it ll break the 200 barrier by Schellnhuber Rahmstorf PIK haters within hours If only this energy could be conserved 23 MS says 2 Oct 2014 at 11 36 AM Thank you Stefan for this post It is a very informative and well documented history of the 2 C limit 24 MARodger says 2 Oct 2014 at 12 24 PM Adam Gallon 7 I believe the 2ºC limit first appeared in 1990 as part of the work of the AGGG The limit thus predates the foundation of the WBGU suggested as the source in the Der Spiegel article mentioned 11 The need to define targets had first been identified at the Vallach Bellagio workshops organised by WMO UNEP ICSU in 1987 which led to the AGGG being formed While some of the 1990 numbers appeared first at Villach Bellagio the 2ºC wasn t among them The development of the targets as described in the full 1990 report was the work of G W HElL and M HOOTSMANS who acknowledge that their temperature targets agree with the temperature targets suggested by the Deutsche Bundestag 1989 Those who can read German may be able to gleen from Deutsche Bundestag ed 1989 Protecting the Earth s Atmosphere An International Challenge what is meant by agreeing Some may find this five page PDF extract from the full report s Preface more managable than the whole thing There is also some rather fanciful comment on line I ve seen that say these limits were first written on the back of a napkin in a Stockholm restaurant presumably after a well lubricated meal Note that the danger engendered is not specifically about mankind but about ecosystems as well as about non linear responses by the climate The 2ºC was only one of six targets two for SLR one CO2e ppm one for rate of surface warming and two absolute temperature targets of which the 2ºC was the higher limit which engenders risks of grave damage to ecosystems rather than just possible extensive ecosystem damage 25 Mike Roddy says 2 Oct 2014 at 1 27 PM Arun re India It remains to be seen if Modi means it His clean energy goals are abstract and in the future India is still building coal power plants for example I hope you re right but I worked in India for a while Modi s political party BJP has strong relationships with local holding companies such as Tata and Reliant They are likely to block any attempts to decarbonize 26 Chris Colose says 2 Oct 2014 at 3 52 PM Unfortunately I think that a lot of the incoherency e g about the hiatus and ocean uptake in the Victor and Kennel piece takes away from a good dialogue on why one could sensibly advocate for multiple climate targets while still not losing sight of the gold standard near zero emissions e g see Ken Caldeira s tweet and further expressed here While zero emissions is a goal that can be made independent of targets the science in particular the questions we can ask of climate models has advanced to the point where we can answer practical questions that policymakers have test the response to mitigation strategies e g temperature response to carbon emitted quantify responses to gases that exhibit feedbacks on atmospheric chemistry or agents like soot that feature climate health co benefits etc this acts to create improved discourse along the halfway point between a step function zero emission extreme and the political reality that such a future won t happen overnight Proposals to extend the 2 C target to other metrics and to better fulfill Article 2 of the UNFCCC have already been advanced e g Steinacher et al 2013 People have also argued that ocean acidification ought to follow under the Article 2 mandate to allow ecosystems to adapt naturally to climate change to ensure that food production is not threatened and to enable economic development to proceed in a sustainable manner However Steinacher et al have shown that temperature targets aren t generally the most restrictive and also you encounter lower probability of meeting multiple targets simultaneously for given emissions than you do for even the most restrictive target on a list of your favorite subset of things we ought to avoid In such cases I don t see much distinction between replacing a 2 C limit and adding to it It is here where I take some issue with Stefan s discussion relating to Figure 2 in the post the arrow chart We already have a very useful vehicle for linking anthropogenic input to impacts discussed here including ocean acidification this whole concept of cumulative carbon emissions Stefan argues that moving further toward the beginning of the causation chain creates extra steps of uncertainty but I d argue that 1 There are countless papers now that rather robustly link peak temperatures roughly linearly to cumulative carbon emissions plus some accounting for short lived non CO2 greenhouse gases and 2 what you lose in creating another step from emissions to temperature to impacts you gain from creating a more tractable and concise metric for policy makers and one that still projects onto non temperature related metrics like ocean acidification So a quick list of where we can make sense of a temperature target 1 If your favorite metric is purely climatic then I basically agree that you can usually scale the severity of most things to global mean temperature This includes the amount of water vapor in the air Arctic warming sea ice loss land warming and I suspect but haven t checked the fraction of global land covered by n sigma temperature extremes at any given time relative to climatology pick your favorite n For more local impacts like rainfall over southern South America these things may be less robustly linked or coupled strongly to other factors e g ozone depletion recovery and the large scale hydrologic cycle but see point 2 below 2 If you consider other forcings e g black carbon or aerosols that force interhemispheric asymmetries or vertical structures in radiation anomalies then you get things like ITCZ migration global precipitation temperature scalings break down etc and start to lose contact between global temperature metrics and changes in the hydrologic cycle things we care about and which still exhibit some robust large scale responses to CO2 forced warming 3 Even for sea level rise even though this relates to temperature SLR continues well after global temperatures stabilize due of heat mixing into the oceans e g Meehl et al 2012 even before you think about slow components associated with ice sheets so you end up with a breakdown in relating temperature to SLR commitments before equilibrium 4 If we extend our interest to ocean acidification then the temperature target is of no validity All of these things can be traceable in some respect to total emissions but there are many value systems in addition to different vulnerabilities risks so I don t see the inherent danger in presenting multiple metrics of what constitutes dangerous What emerges from this is probably a cumulative emission goal that would lead to warming of far less than 2 C as Stefan noted But the logic that this added complexity will hinder political progress is just as odd as the notion that we should dispel of a 2 C target because we won t have the political will to meet it 27 Chris Dudley says 2 Oct 2014 at 4 04 PM Mike Modi feels he has already taken some action on climate prior to becoming PM http www narendramodi in convenient action 2 28 Adam Gallon says 2 Oct 2014 at 4 18 PM I see the problem Extrapolate the trend line out until it reaches the 2C line and we re looking at well into the next century That s not going to frighten anyone sufficiently is it That s why the tack is being changed 29 Rob Ellison says 2 Oct 2014 at 5 22 PM Neither annual variation or decadal changes are the right metric Short term variations are irregular and involve significant changes in global surface temperature http www cru uea ac uk cru data temperature HadCRUT4 png It results in part from significant changes in cloud radiative forcing associated with changes in ocean and atmospheric circulation e g http meteora ucsd edu jnorris reprints Loeb et al ISSI Surv Geophys 2012 pdf The CERES net product look like this http watertechbyrie files wordpress com 2014 06 ceres ebaf toa ed2 8 anom toa net flux all sky march 2000toapril 2014 png What it shows is large variability in TOA radiative flux Earlier ERBS data looks like this http watertechbyrie files wordpress com 2014 06 erbs png It shows a 0 7 W m2 decrease in IR forcing and a 2 1 W m2 increase in SW forcing AR4 s3 4 4 1 This data shows a dominant role for natural warming in the 1976 to 1998 warming although you may always critique the data These are anomalies an order of magnitude more precise than absolute values At the very least it raises some interesting questions The critical multi decadal periods are obvious in the surface record Changes in the trajectory of surface temperature occur in 1909 1944 1976 and 1998 This coincides with shifts in ocean and atmospheric indices Anastasios Tsonis of the Atmospheric Sciences Group at University of Wisconsin Milwaukee and colleagues used a mathematical network approach to analyse abrupt climate change on decadal timescales Ocean and atmospheric indices in this case the El Niño Southern Oscillation the Pacific Decadal Oscillation the North Atlantic Oscillation and the North Pacific Oscillation can be thought of as chaotic oscillators that capture the major modes of climate variability Tsonis and colleagues calculated the distance between the indices It was found that they would synchronise at certain times and then shift into a new state It is no coincidence that shifts in ocean and atmospheric indices occur at the same time as changes in the trajectory of global surface temperature Our interest is to understand first the natural variability of climate and then take it from there So we were very excited when we realized a lot of changes in the past century from warmer to cooler and then back to warmer were all natural Tsonis said The changes at these multi decadal scales would seem to be climatologically significant The complex dynamical mechanism in play suggest on the basis of past behavior that the hiatus could persist for decades Indeed this has been addressed in a past RC post Warming interrupted much ado about natural variation 30 David Small says 2 Oct 2014 at 8 54 PM Their argument was that a hemispheric annual average temperature is not a meaningful metric of anything What is so wrong with a metric that objectively measures bad outcomes for human beings Could it be that by all objective measures of extreme events people and the planet are doing just fine despite a 1 C increase in temperature Why don t we quit wasting our time worrying about meaningless measures of global annual average temperature and worry about how to develop sustainably protect our water resources and distribute natural resources more equitably 31 patrick says 2 Oct 2014 at 9 00 PM 11 The idea didn t hurt his career In fact it made him Germany s most influential climatologist Schellnhuber a theoretical physicist became Chancellor Angela Merkel s chief scientific adviser a position any researcher would envy This is an outright slur because it doesn t say what led this particular and particularly brilliant theoretical physicist to become a climatologist The PNAS profile of H J John Schellnhuber is very helpful It s a biography that is totally intriguing an intrigue not of the Spiegel kind The institute is on the north coast of Germany and specializes in tidal flat research Tidal flats are very peculiar ecosystems he says They are a sort of fractal structure It s interesting how the water is transported and how nutrients are transported through these fractal structures how algae start to settle there Researchers from geology biology and chemistry came to ask him for advice about how to construct a mathematical model for their specialties So I started to become interested in ecosystems he says not because I was a green activist it was simply through sheer scientific curiosity His own group focused on the stability of nonperiodic orbits using Kolmogorov Arnold Moser theory That is probably the most complicated mathematical issue you can do in nonlinear dynamics he says Meanwhile his colleagues in the institute were considering how algae grew in the mud I found it refreshing he says You cannot do 12 hours a day thinking of Kolmogorov Arnold Moser theory There may be some people doing that but in general you do it a few hours a day I found it more enjoyable to talk to people and even go out to the tidal flats to look at the structures http www pnas org content 105 6 1783 full The Spiegel kind of intrigue is happening alright as observed here http www slate com articles health and science science 2014 10 the wall street journal and steve koonin the new face of climate change html Being a smart physicist can just give you more elaborate ways to delude yourself and others along with the arrogance to think you can do so without taking the time to really understand the subject you are discussing If you expose a panel of physicists who are ignorant of climate science to 50 percent wisdom and 50 percent nonsense one cannot hold out much hope for a good outcome 32 Arun says 2 Oct 2014 at 10 10 PM Mike Modi is not going to not industrialize as fast as he can just because he lacks clean energy sources He wants to if he can to the extent possible etc which is why I think he wanted to learn from Americans what might be possible and to what extent they are willing to help Anyway this was India s stand on refrigerant gases before Modi http www thehindu com news national no phasing out refrigerant gases india article5266096 ece This is after Modi http www washingtonpost com national health science obama modi announce modest progress in joint efforts to fight global warming 2014 09 30 c3e7464e 48aa 11e4 b72e d60a9229cc10 story html You can see Obama Modi had some tiny progress I was hoping for much much more Arun 33 Hank Roberts says 2 Oct 2014 at 11 02 PM 2 degrees needs uncertainty bars or gray fuzz around it for the same reason any other number or point or line should be shown as somewhere in this range the slippery slope begins to accelerate http 0 tqn com y grammar 1 G S S blackboard slippery slope jpg All politics takes place on a slippery slope George Will Statecraft as Soulcraft What Government Does Simon Schuster 1983 34 Titus says 3 Oct 2014 at 3 54 AM It appears from the graph that the warming from 1905 to 1945 is a very close match to the rise from 1965 to 2000 Can this be explained in layman terms that make a strong argument that the latest rise is man made whereas the earlier rise was natural I think this is an obvious question from anybody looking at this graph and would be good to have a few words of explanation included 35 Tony Weddle says 3 Oct 2014 at 4 00 AM Thanks Stefan However you seem to be more saying that there is a strong case for a temperature limit rather than there is a strong case for the 2 C limit The UNFCCC wants to avoid dangerous climate change As you ve shown the 2 C limit probably won t do this e g the risk of GIS destabilisation is at 1 C The safe operating space for humanity that you cited puts the safe CO2 concentration at 350 ppm IIRC Hansen et al 2013 puts the possibly safe limit at 1 C possibly because it may be lower Regarding that estimate of the costs of achieving 2 C I understand the IPCC report said that all analyses are incomplete so I m not sure what the benefit of stating an incomplete estimate is especially as it is unknown what the concentration of CO2 has to be limited to to achieve the goal Having an unmoving goal of something one doesn t know how to achieve doesn t seem to me to be an advantage of it If as you say the CO2 concentration needs to be adjusted to keep warming below 2 C then that greatly alters the possibility of achieving the goal So I m not convinced that it is a good goal Hansen s target of 350 ppm seems a much better one it s something tangible but will likely cost far too much so won t be adopted Which leaves us with 36 Kevin McKinney says 3 Oct 2014 at 5 30 AM 26 Mm some of the Modi renewables initiatives seem pretty concrete to me But it s true that there seems little concern on climate the emphasis on solar may be more motivated by the shortcomings of the coal dominated status quo India s new environment minister Prakash Javadekar said in an interview with The New York Times What cuts That s for more developed countries The moral principle of historic responsibility cannot be washed away India s first task is eradication of poverty Twenty percent of our population doesn t have access to electricity and that s our top priority We will grow faster and our emissions will rise http thediplomat com 2014 10 indias renewable energy opportunity 37 Dan H says 3 Oct 2014 at 5 46 AM MA Thanks you the reference It was rather informative Contrary to the post 17 the value was a target rather than a limit There was nothing magical about this value but was a convenient goal It was much easier to target a whole number in subsequent discussion than a fraction as those involved realized that there is a continuum of consequences that will occur as temperatures rise Others jumped on this convenient value and it was incorporated into the previously mentioned documents 38 Sean says 3 Oct 2014 at 7 31 AM Limiting global warming to 2 C why Victor and Kennel are WRONG This article is what is known as a REACTIVE Response to the COGNITIVE FRAMING already created by David Victor and Charles Kennel What we have here is a classical example of the Dog being Wagged by the Tail This approach has and will always FAIL to achieve the Goals of the Author Stefan and Real Climate The only people this article will reach or positively influence are the already True Believers and not the middle ground and definitely not the Political Power Base The only power that is able to effect lasting change This issue of Framing public discourse is well known is scientifically based and has been used in advertising and politics now for over 40 years By defaulting to responding to the specific arguments put by David Victor and Charles Kennel only serves to REINFORCE those very arguments and the overall Framing of the Public discourse This approach is doomed to fail It has never worked and will never work to positively effect any change people s thinking or judgment Change your approach or you will lose not just this minor battle but the whole War at hand The Hook has been baited and Stefan has taken it hook line and sinker To use a fishing METAPHOR It s not an analogy The only solution is to bring in real professionals in public communications and set your own FRAMING of the debate using powerful Linguistic tools that are well known and science based Several come to mind here George Lakoff George Marshall Will Stefan Luke Menzies Will Grant Peter Ward Hans Rosling Kevin Anderson Yale Forum on Climate Change the Media et al Now what if the 2C is wrong anyway Like because it is set too HIGH The article quotes to hold the increase in global average temperature below 2 C above pre industrial levels And yet the facts suggest at least to many that the past 10 20 years projections estimates of the Physical Manifestations in Changes expected from increasing CO2 rising and Temperature increase over pre industrial are OBVIOUSLY occurring much faster than any major body or qualified science group has ever predicted since Rio or before Many several scientists bodies are indicating that 2C is already in the pipeline on the existing CO2 emissions already produced The real question to be asked and answer urgently in my humble opinion is should the below 2C be lowered to below 1C That is the proper framing of the debate that needs to be had the Scientific Public and Political dialogues need to be FRAMED by the Scientific community using Scientific based communication approaches that actually do work and can generate real change This kind of approach means that the focus will not continue to be driven by the likes of the Murdoch Press Der Spiegel Judith Curry nor by David Victor and Charles Kennel Whatever they say will become redundant and irrelevant to the MAJORITY and the global political dialogues AS interesting and factual and logical Stefan article is attempting to debunk the nature article I fear all it has done is brought unnecessary attention to do and allowed them to take the High Ground in this particular battle of to 2C or not to 2C But that ain t the critical question anyway and will answer and solve nothing Peace 39 Hank Roberts says 3 Oct 2014 at 8 19 AM Nordhaus interview story at NPR http www npr org 2014 02 11 271537401 economist says best climate fix a tough sell but worth it 40 jef says 3 Oct 2014 at 9 37 AM Alvin Stone I really appreciate what Dr Mann said in this statement If we miss the 2 C mark it doesn t mean we just stop and give up because 3 C degrees is worse than 2 5 C and 4 C is a whole lot worse So if we miss that exit ramp we still have to

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  • Nenana Ice Classic: Update « RealClimate
    Great Lakes By this winter s weather coverage these were described as related Arctic cold moving south into the US leaving Alaska and the Arctic warmer Maybe attributed to a polar vortex 13 Magma says 27 Apr 2014 at 7 24 PM I wonder what the TV weatherman will be saying over at WUWT this year Probably maintaining a discreet silence http www donotlink com g0j 14 Jodi says 27 Apr 2014 at 7 50 PM I used that graph along with many other graphs charts tables and information to enter the pool this year I chose April 20 21 22 25th 12 25pm That is just a 3H 23M difference We ll see if anyone else is as close or closer than I am and who knows maybe I ll take the cake In doing all of my research there are definite variances from one year to the next however the climate is definitely on a warmer path Just look at Greenland They are now able to prospect areas that have never been accessible before because of glaciers Now the once ice covered land is bare and exposed It is not like a river or lake freeze where they can say Oh the weather was warm this year maybe it will freeze next year Glaciers are moving melting and calving much faster than history has shown 15 mgardner says 28 Apr 2014 at 5 08 AM 3 siloch Yes we need to look at trends in variability as well One of the problems I see in this discussion is a kind of tunnel vision as people get attached to and focus on one variable or the other It would be also be useful if we clarify particularly in discussion with skeptics what exactly is the question we are answering Some effects are good indicators that system energy is increasing while others as you suggest might be more in the category these are the kinds of negative effects we are likely to experience When we fail to make those distinctions we allow skeptics to be the ones framing the debate 16 Steve Metzler says 28 Apr 2014 at 5 08 AM Magma 13 If you don t want a link to boost the PageRank of a site you re linking to just add the rel nofollow attribute like this a href http www example com rel nofollow Link text a Lot easier than having to go through a proxy site 17 Edwardio says 28 Apr 2014 at 9 57 AM Response The point is surely that we have 98 years not 24 gavin Not sure what that you mean And I am not trying to be disagreeable or confrontational My eyes see a graph showing an insignificant 20 year trend with no trend in the prior 50 years or the 24 years since To portend a 98 year trend is to report significance which does not exist Assessing significance accurately matters much With all of our observations 18 Hank Roberts says 28 Apr 2014 at 1 29 PM the rel nofollow attribute Hilight any link above and view source and you ll see that attribute has been added automatically by the browser software here 19 Magma says 28 Apr 2014 at 11 35 PM Steve 16 thanks for the tip that is easier Are there any downsides to using that attribute for example does it break urls on some webpages 20 Eli Rabett says 29 Apr 2014 at 6 35 AM How does this track the average winter temperature Parts of Alaska were very warm this winter 21 WhiteBeard says 29 Apr 2014 at 6 01 PM To follow up my comment 9 with a visual http www alaskadispatch com article 20140428 yukon river communities brace earlier expected breakup The village of Gelana is 230 mi 370 km as the raven flies WNW of the small town of Nenana where the break up tripod is set on the Tanana River s ice every winter The Tanana joints the Yukon 140 mi 230 km above Gelana Eagle s 85 souls are about 10 mi west of the Alaska Yukon boarder and Circle s 100 or so residents are another 110 mi 180 km further down river In general the core regions of Alaska had an exceeding cool ending to winter then transitioned very rapidly to summer to conditions which it sustained at above norms in 2013 April at Nenana was more than 10 ºF below norms and that location only had nights above freezing from May 23rd 22 tegiri nenashi says 29 Apr 2014 at 8 57 PM Can we ignore medium sized city Fairbanks sitting just 50 mi upriver It certainly has grown during last century and who knows what its power and water heating facilities discharge into Tanana river Wouldn t global sea ice cover be a more robust proxy of climate change or the lack of thereof 23 Paul D says 29 Apr 2014 at 11 34 PM 17 Edwardio You don t use your eyes you do a statistical regression analysis and in any regression analysis more data points is always better for the reliability of any inferences There will always be short term fluctuations and 20 years is most decidedly short term 24 Slioch says 30 Apr 2014 at 6 29 AM Well early yesterday I provided a fairly comprehensive and hopefully helpful response to 11 Edwardio including links to some Tamino Open Mind articles that dealt with understanding time series eg Don t get Fooled Again The result I was automatically informed that my post was regarded as spam and had been deleted I emailed direct to Realclimate to ask for this to be remedied but so far my post remains undisplayed I can appreciate that a site like Realclimate may get bombarded with all manner of dross but if its systems and operators are unable to distinguish between dross and genuine posts leading to the latter being deleted then the site s discussions becomes

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  • The Nenana Ice Classic and climate « RealClimate
    at the changing distribution of guesses for Nenana I mean obviously the actual time and date of ice out reflects changes in local climate but the guesses would reflect what people who live in the region perceive as normal which would also be important data 8 Dan H says 9 Mar 2014 at 10 39 AM Yes Magma Selecting those dates would suggest that Just like using 2014 contiguous U S winter temps Conversely choosing 1998 or the U S winter of 2012 would indicate the opposite There is a definitive long term trend and a good correlation with the pdo on shorter intervals 9 John Mashey says 9 Mar 2014 at 1 14 PM This is a nice reminder of a long ago visit to Nenana on way from Denali to Fairbanks I do believe British viticulture has progressed since 2006 and Richard Selley s 2 editions of the The Winelands of Britain are delightful but sadly not easy to buy However from examinination of current data I think there are enough vineyards in Yorkshire to support a wine tour on our next visit there As Gavin notes UK vineyard count is not necessarily a good temperature proxy for various reasons such as varying geology buildover of earlier vineyards different grapes etc Although I don t know of academic studies a better vineyard proxy with fewer confounding factors than uk might be the recent history of Okananagan B C wine region in which vinifera plantings have generally spread northward around a 70 mile long lake Obviously this could only be a recent proxy for mid 20th century temperatures as I doubt there was a medieval wine industry here 10 Kevin McKinney says 9 Mar 2014 at 6 08 PM 9 Ontario too http en m wikipedia org wiki Ontario wine Especially the intrepid souls on the Bruce Peninsula 11 tegiri nenashi says 10 Mar 2014 at 7 53 PM On the ice page there is a lot more info than just the breakout date They have several ice thickness measurements varying from just 6 points 1990 to more than dozen Don t you think a graph based on this data would be more robust 12 Bob says 10 Mar 2014 at 10 46 PM Tamino well that must be it because correlation is always causation Hmm 13 Ray Ladbury says 11 Mar 2014 at 4 54 AM Bob you want to try that comment again but this time try making sense 14 Bob Maginnis says 11 Mar 2014 at 10 24 PM Gavin It is the Tanana River that breaks up at the town of Nenana 15 BillS says 11 Mar 2014 at 10 29 PM In Maine USA ice out the day that a local lake sheds its ice has been a wagering date for 100 years or more Ice out day is both a source of amusement and hope hope that spring is not that far off Data for some of the lakes goes back to about 1850 or earlier The US Geological Survey has compiled data on 29 New England lakes ice out dates Data can be found here me water usgs gov reports OFR02 34 pdf Unfortunately the USGS hasn t updated the data since about 2000 This year may be an outlier 16 Steve Metzler says 12 Mar 2014 at 7 53 AM BillS 15 tamino had this one covered too about 3 years ago in response to yet another lame attempt at WUWT to correlate ice out dates with anything but AGW Ice Out 17 BillS says 12 Mar 2014 at 9 59 AM 16 Steve Metzler Thanks for the link Nice to see someone else bothered to plot the dates While the USGS has stopped compiling the dates Maine s Dept of Parks Lands has ice out dates from 2003 2013 but the list of lakes ponds varies from year to year I suppose an alternative explanation to AGW is that the ice departs when the ice fishermen run out of beer 18 BillS says 12 Mar 2014 at 10 01 AM opps forgot the URL http www maine gov dacf parks archive programs boating ice out03 html 19 Walter says 12 Mar 2014 at 10 46 AM non traditional data sets that can shed some light on climate changes A 6 day per century trend You have got to be kidding or you have waaaaaaaaaaay too much time on your hands to be playing with this and then to also spend the time to write it up as an real article about climate science here or anywhere else Maybe giving a drunk presentation at the xmas party would fit 20 WebHubTelescope says 12 Mar 2014 at 11 46 AM Minnesota is the land of 10 000 lakes and I have a blog post looking at the ice out trends as well http theoilconundrum blogspot com 2012 09 lake ice out dates earlier and earlier html The last year and likely this year are upticks in the ice out date but that is not surprising as it does fluctuate quite a bit Minnesota is large enough that I separated the regression curves out in 1degree latitude zones 21 Gonzo says 12 Mar 2014 at 5 59 PM Interesting if you invert Nenana data it looks a lot like pre adjusted land temp records If I was a betting man I d the trend will be going down later break up dates as the trend since the 98 El Nino i know a cherry pick is certainly down 22 Steve Metzler says 12 Mar 2014 at 8 53 PM Walter 18 Sure the Tanana river at Nenana is one data point Have a look at the 3 Maine lakes that tamino examined in the Ice Out link from my post at 15 Just since 1970 those lakes are icing out 8 10 days earlier That s a pretty significant trend And worrying for those that appreciate the implications of such Liked the science

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  • Climate impacts « RealClimate
    Instrumental Record gavin 7 March 2014 I am always interested in non traditional data sets that can shed some light on climate changes Ones that I ve discussed previously are the frequency of closing of the Thames Barrier and the number of vineyards in England With the exceptional warmth in Alaska last month which of course was coupled with colder temperatures elsewhere I was reminded of another one the Nenana Ice Classic More Comments pop up 28 Thames Barrier raised again Filed under Climate impacts Climate Science gavin 14 January 2014 Back in 2007 I wrote a post looking at the closures of the Thames Barrier since construction finished in 1983 Since then there has been another 7 years of data and given that there was a spate of closures last week due to both river and tidal flooding it seems a good time to revisit the topic More Comments pop up 40 From global climate change to local consequences Filed under Climate impacts Climate modelling Climate Science Communicating Climate IPCC Reporting on climate rasmus 3 November 2013 Some will be luckier than others when it comes to climate change The effects of a climate change on me will depend on where I live In some regions changes may not be as noticeable as in others So what are the impacts in my region More Comments pop up 13 Older Entries Newer Entries Site Google Custom Search Recent Comments What is the best description of the greenhouse effect Jim Eager What is the best description of the greenhouse effect Patrick Eriksson What is the best description of the greenhouse effect Kevin McKinney Anti scientists Carbomontanus What is the best description of the greenhouse effect Spencer Marvel et al 2015 Part III Response to Nic Lewis SteveS What is the best description of the greenhouse effect Chris Colose Blizzard Jonas and the slowdown of the Gulf Stream System doiknow What is the best description of the greenhouse effect James Powell Unforced Variations Feb 2016 Jim Galasyn With Inline Responses Marvel et al 2015 Part III Response to Nic Lewis SteveS Marvel et al 2015 Part III Response to Nic Lewis steve s Marvel et al 2015 Part III Response to Nic Lewis Andrew Kerber Blizzard Jonas and the slowdown of the Gulf Stream System Hank Roberts Blizzard Jonas and the slowdown of the Gulf Stream System doiknow Marvel et al 2015 Part III Response to Nic Lewis MartinM Anti scientists Don McKenzie Marvel et al 2015 Part III Response to Nic Lewis Matt Skaggs Anti scientists mikeworst New On line Classes and Models Marcus Pages Acronym index Data Sources Categories Climate Science Aerosols Arctic and Antarctic Carbon cycle Climate impacts Climate modelling El Nino Geoengineering Greenhouse gases Hurricanes Instrumental Record IPCC Oceans Paleoclimate Sun earth connections Communicating Climate Reporting on climate skeptics Extras Attic Comment Policy Contributor Bio s FAQ Glossary In the News Reviews Supplemental data Tutorials hydrological cycle Open thread RC Forum Scientific practice statistics The Bore Hole Books

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  • Climate impacts « RealClimate
    twentieth century slowdown in Atlantic Ocean overturning circulation Nature Climate Change vol 5 pp 475 480 2015 http dx doi org 10 1038 nclimate2554 Comments pop up 33 Limiting global warming to 2 C why Victor and Kennel are wrong update Filed under Climate impacts Climate Science Instrumental Record IPCC stefan 1 October 2014 In a comment in Nature titled Ditch the 2 C warming goal political scientist David Victor and retired astrophysicist Charles Kennel advocate just that But their arguments don t hold water It is clear that the opinion article by Victor Kennel is meant to be provocative But even when making allowances for that the arguments which they present are ill informed and simply not supported by the facts The case for limiting global warming to at most 2 C above preindustrial temperatures remains very strong Let s start with an argument that they apparently consider especially important given that they devote a whole section and a graph to it They claim The scientific basis for the 2 C goal is tenuous The planet s average temperature has barely risen in the past 16 years More Comments pop up 71 Nenana Ice Classic Update Filed under Climate impacts Climate Science Instrumental Record gavin 25 April 2014 Somewhat randomly my thoughts turned to the Nenana Ice Classic this evening only to find that the ice break up had only just occurred 3 48 pm Alaskan Standard Time April 25 This is quite early the 7th earliest date regardless of details associated with the vernal equinox or leap year issues though perhaps unsurprising after the warm Alaskan winter this year 8th warmest on record This is in strong contrast to the very late break up last year Break up dates accounting for leap years and variations in the vernal equinox As mentioned in my recent post the Nenana break up date is a good indicator of Alaskan regional temperatures and despite last year s late anomaly the trends are very much towards a earlier spring This is also true for trends in temperatures and ice break up mostly everywhere else too despite individual years like 2013 2014 being anomalously cold for instance in the Great Lakes region As we ve often stressed it is the trends that are important for judging climate change not the individual years Nonetheless odds on dates as early as this years have more than doubled over the last century Comments pop up 29 Older Entries Site Google Custom Search Recent Comments What is the best description of the greenhouse effect Patrick Eriksson What is the best description of the greenhouse effect Kevin McKinney Anti scientists Carbomontanus What is the best description of the greenhouse effect Spencer Marvel et al 2015 Part III Response to Nic Lewis SteveS What is the best description of the greenhouse effect Chris Colose Blizzard Jonas and the slowdown of the Gulf Stream System doiknow What is the best description of the greenhouse effect James Powell Unforced Variations Feb 2016

    Original URL path: http://www.realclimate.org/index.php/archives/category/climate-science/climate-impacts/%5C (2016-02-13)
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