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  • October « 2011 « RealClimate
    recently released its first results on ocean salinity The patterns are not particularly surprising there is higher salinity in the sub tropical evaporative regions lower salinity near the equator because of the rain and particularly low salinity near big river outflows the Amazon plume stands out clearly However as we noted earlier the main interest is going to be in the variability Results from the NPP mission will take a while to come out and be cross calibrated with the existing records but given other recent disappointments GLORY and OCO this is a huge boost to the effort to monitor the Earth System Comments pop up 35 The Moscow Warming Hole Filed under Climate Science stefan 26 October 2011 This week PNAS published our paper Increase of Extreme Events in a Warming World which analyses how many new record events you expect to see in a time series with a trend It does that with analytical solutions for linear trends and Monte Carlo simulations for nonlinear trends A key result is that the number of record breaking events increases depending on the ratio of trend to variability Large variability reduces the number of new records which is why the satellite series of global mean temperature have fewer expected records than the surface data despite showing practically the same global warming trend they have more short term variability Another application shown in our paper is to the series of July temperatures in Moscow We conclude that the 2010 Moscow heat record is with 80 probability due to the long term climatic warming trend More Comments pop up 113 Berkeley earthquake called off Filed under Climate Science eric 24 October 2011 Anybody expecting earthshaking news from Berkeley now that the Berkeley Earth Surface Temperature group being led by Richard Muller has released its results had to be content with a barely perceptible quiver As far as the basic science goes the results could not have been less surprising if the press release had said Man Finds Sun Rises At Dawn This must have been something of a disappointment for anyone hoping for something else More Comments pop up 208 Older 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

    Original URL path: http://www.realclimate.org/index.php/archives/2011/10/ (2016-02-13)
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  • September « 2011 « RealClimate
    Arctic and Antarctic Climate Science gavin 21 September 2011 After a record breaking 2010 in terms of surface melt area in Greenland Tedesco et al 2011 numbers from 2011 have been eagerly awaited Marco Tedseco and his group have now just reported their results This is unrelated to other Greenland meltdown this week that occurred at the launch of the new Times Atlas More References M Tedesco X Fettweis M R van den Broeke R S W van de Wal C J P P Smeets W J van de Berg M C Serreze and J E Box The role of albedo and accumulation in the 2010 melting record in Greenland Environ Res Lett vol 6 pp 014005 2011 http dx doi org 10 1088 1748 9326 6 1 014005 Comments pop up 109 Hooked on theWeather Filed under Climate Science Communicating Climate Reporting on climate rasmus 16 September 2011 During the annual European Meteorological Society s EMS annual meeting in Berlin I was pleasantly surprised by a magazine called theWeather issued by the theWeather Club an outreach activity associated with the Royal Meteorological Society TheWeather Club was awarded the EMS outreach Communication award 2011 for this magazine More Comments pop up 64 The unnoticed melt Filed under Arctic and Antarctic Climate modelling Climate Science group 9 September 2011 Guest commentary from Dirk Notz MPI Hamburg Well it s not really good timing to write about global warming when the summer feels cold and rainy a journalist told me last week Hence at least here in Germany there hasn t been much reporting about the recent evolution of Arctic sea ice despite the fact that Arctic sea ice extent in July for example was the lowest ever recorded for that month throughout the entire satellite record Sea ice extent in August was also extremely low second only to August 2007 Fig 1 Whether or not we re in for a new September record the next weeks will show Figure 1 Evolution of Arctic sea ice extent in July and August from 1979 until 2011 NSIDC More Comments pop up 172 Resignations retractions and the process of science Filed under Climate Science Reporting on climate gavin 6 September 2011 Much is being written about the very public resignation of Wolfgang Wagner from the editorship of Remote Sensing over the publication of Spencer and Braswell 2011 and rightly so It is a very rare situation that an editor resigns over the failure of peer review and to my knowledge it has only happened once before in anything related to climate science the mass resignation of 6 editors at Climate Research in 2003 in the wake of the Soon and Baliunas debacle Some of the commentary this weekend has been reasonable but many people are obviously puzzled by this turn of events and unsupported rumours are flying around More Comments pop up 118 Older Entries Site Google Custom Search Recent Comments What is the best description of the greenhouse effect Jim Eager What is

    Original URL path: http://www.realclimate.org/index.php/archives/2011/09/ (2016-02-13)
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  • August « 2011 « RealClimate
    around that I think are noteworthy the use of more interactive Earth System models a focus on initiallised decadal predictions and the inclusion of key paleo climate simulations as part of the suite of runs The term Earth System Model is a little ambiguous with some people reserving that for models that include a carbon cycle and others including me using it more generally to denote models with more interactive components than used in more standard AR4 style GCMs i e atmospheric chemistry aerosols ice sheets dynamic vegetation etc Regardless of terminology the 20th Century historical simulations in CMIP5 will use a much more diverse set of model types than did the similar simulations in CMIP3 where all models were standard coupled GCMs That both expands the range of possible evaluations of the models but also increases the complexity of that evaluation The decadal prediction simulations are mostly being run with standard GCMs see the article by Doblas Reyes et al p8 The different groups are trying multiple methods to initialise their ocean circulations and heat content at specific points in the past and are then seeing if they are able to better predict the actual course of events This is very different from standard climate modelling where no attempt is made to synchronise modes of internal variability with the real world The hope is that one can reduce the initial condition uncertainty for predictions in some useful way though this has yet to be demonstrated Early attempts to do this have had mixed results and from what I ve seen of the preliminary results in the CMIP5 runs significant problems remain This is one area to watch carefully though Personally I am far more interested in the inclusion of the paleo component in CMIP5 see Braconnot et al p15 Paleo climate simulations with the same models that are being used for the future projections allow for the possibility that we can have true out of sample testing of the models over periods with significant climate changes Much of the previous work in evaluating the IPCC models has been based on modern period skill metrics the climatology seasonality interannual variability the response to Pinatubo etc but while useful this doesn t encompass changes of the same magnitude as the changes predicted for the 21st Century Including tests with simulations of the last glacial maximum the Mid Holocene or the Last Millennium greatly expands the range of model evaluation see Schmidt 2010 for more discussion The CLIVAR newsletter has a number of other interesting articles on CFMIP p20 the scenarios begin used RCPs p12 the ESG data delivery system p40 satellite comparisons p46 and p47 and the carbon cycle simulations p27 Indeed the range of issues covered I think presages the depth and interest that the CMIP5 archive will eventually generate There will be a WCRP meeting in October in Denver that will be very focused on the CMIP5 results and it is likely that much of context for the AR5

    Original URL path: http://www.realclimate.org/index.php/archives/2011/08/ (2016-02-13)
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  • July « 2011 « RealClimate
    merit whatsoever in this paper It turns out that Spencer and Braswell have an almost perfect title for their paper the misdiagnosis of surface temperature feedbacks from variations in the Earth s Radiant Energy Balance leaving out the On Comments pop up 282 CRUTEM3 data release except Poland Filed under Climate Science Instrumental Record gavin 27 July 2011 The entire CRUTEM3 database of station temperature measurements has just been released This comes after a multi year process to get permissions from individual National Weather Services to allow the passing on of data to third parties and from a ruling from the UK ICO All the NWSs have now either agreed or not responded except for Poland which specifically refused Since the Polish data is a such a small fraction of the globe and there are a few Polish stations in any case via RBSC or GCOS this doesn t make much difference to hemispheric means or regional climate These permissions were obtained with help from the UK Met Office who have also placed the station data on their website in a slightly different format and whose FAQ is quite informative This dataset has occasionally come up in blogospheric discussions Comments pop up 74 Reanalyses R Us Filed under Climate modelling Climate Science Instrumental Record gavin 26 July 2011 There is an interesting new wiki site Reanalyses org that has been developed by a number of groups dedicated to documenting the various reanalysis products for atmosphere and ocean that are increasingly being made available For those that don t know a reanalysis is a climate or weather model simulation of the past that includes data assimilation of historical observations The observations can be very comprehensive satellite in situ multiple variables or relatively sparse say sea level pressure only and the models themselves are quite varied Generally these models are drawn from the weather forecasting community at least for the atmospheric components which explains the odd terminology An analysis from a weather forecasting model is the 6 hour say forecast from the time of observations Weather forecasting groups realised a decade or so ago that the time series of their weather forecasts the analyses could not be used to track long term changes because their models had been updated many times over the decades Thus the idea arose to re analyse the historical observations with a single consistent model These sets of 6 hour forecasts using the data available at each point are then more consistent in time and presumably more accurate that the original analyses were The first two reanalysis projects NCEP1 and ERA 40 were groundbreaking and allowed a lot of analysis of the historical climate around 1958 or 1948 onwards that had not been possible before Essentially the models are being used to interpolate between observations in a hopefully physically consistent manner providing a gridded and complete data set However there are noted problems with this approach that need to be borne in mind The most important issue is

    Original URL path: http://www.realclimate.org/index.php/archives/2011/07/ (2016-02-13)
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  • June « 2011 « RealClimate
    CV as a proper paper or indeed a journal does not want to accept a comment for some reason Less nobly comments are sometimes avoided to try to prevent the original authors from having the last word However there is a risk that this paper never gets published at all perhaps because it has less than one LPU or it isn t very good or it clearly nothing more than a comment on a previous paper or the authors lose enthusiasm In that case the criticism and any response to it from the original authors if they were asked to respond simply disappears from sight While possible in my experience it is very rare that the critics then turn back to the official comment route It is very unusual for any scientific paper to the last word on anything and there are almost always things that in retrospect one would have done differently So it is not surprising that questions get raised through all this that the original authors might want to tackle without themselves submitting a whole other paper Theoretically most papers would benefit from a well refereed post publication commentary Yet without a formal mechanism to shepherd this process this material generally falls through the cracks As readers might have surmised this is leading up to something Two papers that I was an author or co author on in recent years generated a fair amount of blog commentary Schmidt 2009 in IJoC and Benestad and Schmidt 2009 in JGR mostly because they were explorations of issues raised by authors critical of the mainstream view of climate science Despite the blog discussions however in neither case was a comment response pair published A comment was submitted on Schmidt 2009 by Jos de Laat but this did not pass peer review rightly I think and no more has been heard of it In both cases however other authors whose work was criticised specifically Ross McKitrick and Nicola Scafetta submitted new papers to the same journal that were effectively just extended comments A couple of valid points were made but much in the draft texts was either wrong or irrelevant I was asked to respond to both submissions by the editors involved and did so in the form of a signed draft response as if the papers had indeed been submitted as comments In both cases however the papers were eventually rejected A similar paper by McKitrick and Nierenberg appeared in another journal while Scafetta s paper has not been seen again So why bring this up now The fact is well crafted comments and responses on both these papers would have been a useful contribution to the literature and it is a shame that this didn t happen as I stated in at least one of the responses That the authors were unwilling to submit just a comment for whatever reason is part of the story but it is not clear that any actual comment would have stuck to the

    Original URL path: http://www.realclimate.org/index.php/archives/2011/06/ (2016-02-13)
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  • May « 2011 « RealClimate
    highly uncertain My Jim one criticism is that I would like to have seen this this point made with reference to experimental or model results The plant ecology and or agriculture discussions would have been a good place to do so given the complexities uncertainties involved The authors strongest points are arguably those dealing directly with well defined and direct human health concerns having demonstrated relationships with well understood climate dynamics Several important points of the book relate to biological thresholds These are ubiquitous in biology at all scales and are illustrated nicely in several places a particularly good example is the effect of temperature changes on malarial epidemiology Malaria is caused by species of single celled parasites in the genus Plasmodium vectored by mosquitoes primarily in the genera Aedes and Anopheles between many vertebrate hosts including humans Debilitating to lethal in effects the disease also comprises a fascinating scientific story This includes for example the effects of weather climate on the population dynamics of rapidly reproducing cold blooded organisms and the epidemiology of disease spread and interesting textbook cases in genetics and evolution as well Dan Ferber Epstein and Ferber describe how small changes in temperature can lead to large changes in malarial dynamics This is a function of both insect and parasite life cycle development time both of which are typically non linear These in turn have non linear effects on malarial epidemiology via changing spatial patterns of temperature and precipitation combined with the spatial pattern of human populations and the genetic resistance to malaria therein So full Plasmodium falciparum development that takes 56 days at 18 degrees C but only 19 days at 22 degrees has very significant implications for a mosquito host that lives only 3 weeks maximum it allows the full development of malarial parasites which are not possible at the lower temperature The insect population dynamic also matters which in an aquatic breeder like mosquitoes will be a function of both temperature and the existence of water reservoirs having a 3 week lifetime which in turn are a function of precipitation intensity and frequency Insect population threshold effects are also discussed in a later chapter devoted to the topic of tree mortality and bark beetle dynamics in western North America The forest that really should not be missed for the trees here is the importance of these non linear dynamics in response to climate change Considering that many biophysical systems are webs that are considerably more complex than the examples provided it takes little imagination to realize the potentially high levels of unpredictability that are quickly reached And this should give any reasonable person and society concern about the consequences of forcing the climate into a state that is without precedent in modern society Science is difficult enough when equilibrium states are the study focus let alone when strongly forced and thus transient Environmental health also includes non biological stressors such as environmental chemicals food water and air quality social upheavals etc Epstein and Ferber address these broader issues as well For example one chapter is devoted entirely to air quality composition and its effects on a wide ranging and chronic disease asthma They also recognize that global change is not just climatic They describe for example the multiple causes of health effects in places like Honduras resulting from the combined effects of mangrove clearing and shrimp farming gold mining El Nino changes and hurricanes each contributing its part to an unhealthy and unsustainable condition Drs Paul Epstein and Steve Gloyd and a Mozambican colleague in Caia Mozambique in 1978 L to R Figure 1 from book The book is also not shy about engaging controversial topics or discussing the disinformation campaign For example Kenyan malarial epidemiologist Andrew Githeko was targeted a decade ago after his model based predictions of the spread of malaria into the highlands of East Africa where it is currently expanding but was historically absent due to the temperature limitations that altitude brings Several of the tactics of denial that are well known to RC readers are discussed Nor are the authors afraid to discuss issues in the socio political world that drive many of the human behaviors that are leading to climate change as well as the unequal suffering that will be experienced due to inequalities in wealth And neither are they reluctant to address the multiple social and environmental costs of fossil fuels such as coal Once trained in making connections across disciplines well the habit tends to express itself In the discussions of climate per se there are a few minor inaccuracies in an otherwise sound discussion of what is known However none of these has any bearing on the bigger picture portrayed For instance the book discusses the essentially non existent effect of El Nino Southern Oscillation on the Gulf stream it is possible that the authors actually had the ocean currents off the Peruvian and Equatorial coasts in mind There is also a misconception in the book s introduction about the strength of a greenhouse and the thickness of the glass panes but this does not translate to the greenhouse effect This is however noted later in the book so the inconsistency is just a glitch The book also asserts that global warming will lead to more storms which is still a disputed issue The situation regarding glaciers on Mt Kenya is probably more complicated than just a question about temperature changes in precipitation pattern will also affect their mass balance The authors are critical towards certain multinational corporations discussing for example the role of economic hit men e g John Perkins And although the book covers many topics it does not discuss population growth and it touches on communication issues only lightly in discussing why the world has so far failed to act on climate change This is somewhat ironic given that the book is one of the best examples we have yet seen regarding the effective communication of climate change issues It suffices

    Original URL path: http://www.realclimate.org/index.php/archives/2011/05/ (2016-02-13)
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  • April « 2011 « RealClimate
    methane the dominant component of shale gas Seeing how this specific piece of science is being brought into a policy debate is rather interesting More Comments pop up 88 An Emerging View on Early Land Use Filed under Climate Science group 15 April 2011 Guest article by William Ruddiman More than 20 years ago analyses of greenhouse gas concentrations in ice cores showed that downward trends in CO2 and CH4 that had begun near 10 000 years ago subsequently reversed direction and rose steadily during the last several thousand years Competing explanations for these increases have invoked either natural changes or anthropogenic emissions Reasonably convincing evidence for and against both causes has been put forward and the debate has continued for almost a decade Figure 1 summarizes these different views More Comments pop up 98 The warm beer chart Filed under Climate impacts Climate Science IPCC gavin 13 April 2011 Perhaps a way to connect with Joe Sixpack Tagline If we can pay as much attention to the Earth as we do to our beer we probably wouldn t need to worry about global warming Design by S Han loosely based on IPCC 2007 courtesy of the Artist as Citizen initiative Full size pdf version Comments pop up 55 Older 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 Contributors Highlights Dummies Guide to the latest Hockey Stick controversy El Nino Global Warming and Anomalous U S Winter Warmth Hurricanes and

    Original URL path: http://www.realclimate.org/index.php/archives/2011/04/ (2016-02-13)
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  • March « 2011 « RealClimate
    airborne ground penetrating radar studies of the Antarctic Ice Sheet is a great example The ice sheets themselves are the biggest challenge for climate modelling since we don t have direct evidence of the many of the key processes that occur at the ice sheet base for obvious reasons nor even of what the topography or conditions are at the base itself And of course the future fate of the ice sheets and how they will dynamically respond to climate warming is hugely important for projections of sea level rise and polar hydrology The fact that ice sheets will respond to warming is not in doubt note the 4 6 m sea level rise during the last interglacial but the speed at which that might happen is highly uncertain though the other story this week shows it is ongoing More Comments pop up 119 Wahl to Wahl coverage Filed under Climate Science IPCC gavin 9 March 2011 Eugene Wahl asked us to post a statement related to some incorrect claims circulating in the blogosphere The Daily Caller blog yesterday contained an inaccurate story regarding a correspondence that was part of the emails hacked from East Anglia University Climate Research Unit CRU in November 2009 For the record while I received the email from CRU as forwarded by Dr Mann the forwarded message came without any additional comment from Dr Mann there was no request from him to delete emails At the time of the email in May 2008 I was employed by Alfred University New York I became a NOAA employee in August 2008 The emails I deleted while a university employee are the correspondence I had with Dr Briffa of CRU regarding the Fourth Assessment Report of the Intergovernmental Panel on Climate Change all of which have been in the public domain since the CRU hack in November 2009 This correspondence has been extensively examined and no misconduct found As a NOAA employee I follow agency record retention policies and associated guidance from information technology staff Dr Eugene R Wahl March 9 2011 Further questions can be addressed to Katy G Human at noaa gov Our comments These claims are simply the latest attempt to try and manufacture scandals and smear scientists particularly Mike Mann based on the UEA emails The story appears likely to have come from Senator Inhofe s office who presumably had access to the transcripts taken by the NOAA Office of the Inspector General whose investigation found no evidence of any wrongdoing by NOAA employees The story was planted with Steve McIntyre Anthony Watts and Chris Horner and then linked to by Inhofe s office to provide a little plausible denialability a rather blatant media spin operation But the facts of the case do not support the narrative they are pushing at all While Jones original email was certainly ill advised as we stated immediately it came to light in Nov 2009 Eugene Wahl was not subject to FOIA at the time since he was

    Original URL path: http://www.realclimate.org/index.php/archives/2011/03/ (2016-02-13)
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