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Comments 1 to 50:

  1. citizenschallenge at 13:17 PM on 29 March 2015
    New measurements confirm extra heating from our carbon dioxide


    I'm hoping you can help clarify something for me.  Jim Steele makes a novel suggestion regarding Heat Waves.  It seems wrong on a number of levels, but I sure can't put it together into words.  I'm hoping you can help, here's the quote:

    "every heat wave get's trumpeted as global warming, but the heat waves usually occur under very dry conditions. Dry conditions allow the earth and air to heat up much more quickly. And when you get this high pressure settle in, it allows for greater solar insolation, that heats the land more quickly and that high pressure dome stops convection that would carry away that heat, much like rolling up the windows in your car, watching your car heat up.

    And because water vapor makes up 80% of the greenhouse gases or even more, the heat waves are actually happening when there's a drop in the concentration of greenhouse gases."

  2. New measurements confirm extra heating from our carbon dioxide

    MarkR @20 Allen et. al. 2014 is included in the graphic.  The error bars make it practically worthless compared to hansen and sato 2010, though it does give a higher mean value as shown on the graphic above.

  3. The UK winter of 2014-15: another Tabloid FAIL

    Another problem that someone on Facebook pointed out to me is the Boy that cried Wolf syndrome. One of these days there could well be a severe low-level blizzard of 1947 magnitude affecting a large swathe of the UK and some people, having read these Tabloid stories over so many years, will misguidedly elect to ignore the deadly serious UKMO warnings, to their great risk. A 50cm fall of level snow with a force 9 gale behind it, while statistically very rare, could quite feasibly happen one winter and it could cause an awful lot of casualties if the public ignore what the best of the science says.

  4. One Planet Only Forever at 00:53 AM on 29 March 2015
    The UK winter of 2014-15: another Tabloid FAIL

    The sensationalized regional forecasts of what could happen more than a few days into the future are indeed a problem. They lead some people to believe that the difficulty in predicting such things must mean there is no way anyone can reliably model the future global climate.

    This potential to develop misunderstanding, or mistrust, of the ability to model forecasts of global climate may be the motive behind some of the Tabloid nonsense, especially by Tabloids owned by deliberate disbelievers of climate science like Murdoch.

    Another consequence of the poorly substantiated sensationalized 'predictions' is the association of those 'failed' predictions with other important climate forecasting that has the potential to be correct and require preventative measures to be implemented 'just in case'. A good example was the recent potential massive Blizzard event predicted for New York city. The storm track was further east than it might have been and as a result Boston and other locations got walloped in the way that New York might have been. The fact that New York was spared was seen by many to be proof of unnecessary sensationalizing of what might have happened. That attitude in a population is what leads to tragedies like Katrina where many people were left at risk in a city that was at serious risk because of a lack of interest in making the changes and improvements identified the last time a big hurricane hit the region because "it might not really be all that bad again soon". In advance of Katrina the residents of New Orleans understood that the freeway system not being elevated all the way through the city was a major concern, and indeed they were correct. And the city did not have any plans to move the poor who had no where to go and no way to get there.

    Not all of these sensationalized predictions will be failures. And New Orleans would have suffered worse if the eye of Katrina and tracked west of the track it actually followed, just as New York was fortunate the Blizzard storm track was not further west than it ended up.

    It is important to differentiate between the reliability of near term regional forecasts, especially the potential variability of storm tracks as little as one day in advance, from the more absured claims made about the regional expected weather more than one week into the future. And whenever that clarification of understanding is presented the completely different reliablity of global climate forecasting of general conditions averaged over many years should be mentioned. More people need to understand that the average contitions in the future can be very reliably forecast, in spite of the variability of the accuracy of near term regional forecasts.

  5. Ipso proves impotent at curbing the Mail's climate misinformation

    A Major US church has labelled climate deniers as immoral. Dr. Martha Stout in The Sociopath Next Door claims 4% of people are sociopaths. Mr. Rose may be both.

  6. Ipso proves impotent at curbing the Mail's climate misinformation

    I couldn't find information on the IPSO website, but I can only assume that it is funded by the news industry, with membership from that industry. I wouldn't count on IPSO doing anything.

  7. Ipso proves impotent at curbing the Mail's climate misinformation

    Well, I've just send IPSO an email and tell them what I think, politely, of course. I think this kind of legitimate pressure is vastly underestimated.

  8. The UK winter of 2014-15: another Tabloid FAIL

    The first thing we need to ask about tabloid articicles is " is this a Murdoch rag?"  If the answer is "yes" then we can discount any opinion or editorial therein. If the answer is "no" then there may well be some intelligent, considered and even perhaps scientificically based opinion.  Murdoch has alligned himself with the far right, science denying, "greed is good", "develop at all costs" bunch, so we cannot hope to have rational or considered opinon or commentary from his publications.  There are probably other ratbag media owners that I'm not aware of as a resident of OZ, where his influence is known as the murdocracy.

  9. Ipso proves impotent at curbing the Mail's climate misinformation

    As an outsider it seems to me that IPSO is at best useless and worst incompetent.

  10. Climate change in the Arctic is messing with our weather

    Arctic sea ice hit its annual peak early this year, and climate scientists say the region's below-average ice conditions made this year's maximum extent the lowest on record.

    Every year, Arctic sea ice — ice that forms and floats in Arctic waters — grows during the winter and typically reaches its peak in March. A new report from the National Snow & Ice Data Center (NSIDC), however, reveals this year's Arctic sea ice likely reached its maximum extent earlier than expected, on Feb. 25. At this peak, sea ice covered 5.61 million square miles (14.54 million square kilometers) — the lowest maximum extent since satellite record keeping began in 1979.

    The authors of the NSIDC report also found below-average ice conditions everywhere except in two regions of the North Atlantic Ocean: the Labrador Sea and the Davis Strait. [Images of Melt: Earth's Vanishing Ice]

    Researchers have seen fluctuations in the date of the sea ice's peak, with it occurring as early as Feb. 24 in 1996 and as late as April 2 in 2010. Still, this year's maximum extent occurred 15 days earlier than the March 12 average calculated from 1981 to 2010.

    The Arctic ice cap grows and shrinks with the seasons, and changes in the region's ice cover are largely dictated by variations in sunlight, temperature and weather conditions.

    This year's maximum extent was 425,000 square miles (1.10 million square km) below the average from 1981 to 2010 of 6.04 million miles (15.64 million square km). This year's ice cover was also 50,200 square miles (130,000 square km) lower than the previous record low set in 2011.

    Ice growth this winter lagged behind last year's progress, partly due to unusual patterns in the jet stream in February that created warm pockets over the Bering Sea and the Sea of Okhotsk, in the western Pacific Ocean, according to the NSIDC.

    Yet, officials say a late-season boost in ice growth may still be possible.

    "Over the next two to three weeks, periods of increase are still possible," NSIDC scientists wrote in the report. "However, it now appears unlikely that there could be sufficient growth to surpass the extent reached on February 25."

    The NSIDC is expected to release a full analysis of this winter's sea-ice conditions in early April.

    Moderator Response:

    [DB] Please do not plagiarize the works of another and represent it as your own creation.  Subsequent such infractions will be summarily deleted and could result in a suspension of your commenting privileges here.

    Plagiarized text stricken.

  11. Climate's changed before

    ZMathblasterZ, the first and foremost thing to keep in mind is that CO2 absorbs/emits at various pressure-broadened bands within the thermal infrared range, the range within which the sun-warmed Earth emits.  The emission is in random direction, effectively half up half down.  The process lengthens--in space and time--the path of energy from surface to space.

    Downwelling thermal radiation has been directly measured from the surface.

    So an increase in CO2 is going to result in an increase in energy storage, regardless of the situation.  Beyond that, though, there are interesting questions about the timing of the CO2 amplification effect in the process of the Pleistocene glacial cycles.

  12. ZMathblasterZ at 08:46 AM on 28 March 2015
    Climate's changed before

    Wondering if there are better studies on the idea that CO2 preceded a temperature rise. Ex. More than one warming event. 

    Looking at that abstract are there any studies that support the idea of cause? There is a lot of correlation here but no causality.

    Also is there any additional data on the role on methane in the past events and its involvment in warming and extinction related activity?

    Moderator Response:

    [TD] In all of the following Skeptical Science posts, after you read the Basic tabbed pane, read the Intermediate and then Advanced if they exist:

    And "It's Methane."

    The Search field at the top left of every page is useful.

  13. New measurements confirm extra heating from our carbon dioxide

    jja @17:

    Is this the sort of thing you've been looking for? We now have estimates of the TOA imbalance in each decade.

  14. There's no empirical evidence

    @MA Rodger,

     Sorry for the delay in replies. I realise I have probably poorly stated my argument. So I found a presentation explaining it online. I realise the presentation is not the same weight as a scientific study or even a synthesis. But I hope this will explain my position with more clarity. Please explain to me where you believe this guy is wrong. That will give you context and me a place to start digging.

    PS. You said, "That in itself would be a wonderful thing to achieve if it were possible but it would require a change in agricultural practices worldwide to get such a result, a task almost as difficult as weaning mankind off the fossil fuels which is the primary cause of our problem." I would counter with the fact the green revolution happened almost overnight. A similar change to a carbon farming revolution could be equally rapid in my opinion.

  15. New measurements confirm extra heating from our carbon dioxide

    Theo @5:
    Quick answer is: they did compare measurements to theory and found the model did excellently, see Figure 1 in the paper.

    Your equation is an approximation from Myhre et al. (1998). It's for net change in flux at the tropopause after allowing the stratosphere to adjust, and averaged over 3 different atmospheres (tropical, northern and southern).

    This experiment has measurements from two land surface locations, both Northern Hemisphere, only clear-sky and including changes in temperature and water vapour.

    Since CO2 and water vapour have some absorption band overlap, then they each steal some heating from the other. So if you increase CO2 without increasing water vapour (like in Myhre et al) then the calculated CO2 effect should be bigger than the case where water vapour increases (like in this experiment). That's just one reason why we should be careful with the comparison.

    Both Myhre et al. and this study use line-by-line models that are astonishingly accurate (e.g. Tjemkes et al., 2003). These new measurements gives us even more confidence that these models can be used to estimate radiative forcing.

    We'd already checked these models "in the wild", and satellite measurements also back up expected changes (e.g. Harries et al., 2001). This new study seems to be built on a top quality experiment, but we already had enough experimental evidence to be very confident in the radiative transfer models used to calculate radiative forcing.

  16. The UK winter of 2014-15: another Tabloid FAIL

    well written I couldn't agree more these forecasters want stopping all it's doing is frightening old people with these horror stories.I used to get it when my mother was alive she used to take the Express and would always take notice of what was written about the weather and she would be worring if the cares would be able to get,or I would get to do the shopping.What about all the businesses who have taken notice and over stocked with winter clothing,snow moving equipment which the can't sell because it's been so mild. Here in Lincolnshire we have had very little snow you woudn't be able to build a snowman or have a snow ball fight,didn't even have to clear the driveway.The Express and Madden should write an apology to all the old people and businesses that have been taken for a ride.what about the Easter headlines saying it is going to be cold and wet when 2 weeks ago they were printing headlines it was going to be the hottest Easter on record,its not good for the businesses on the coast with these reports. Kind Regards  P. Hewitt

  17. Climate sensitivity is low

    @316, you mean I've got more reading to do? 

  18. It's not bad

    As an example: if a man on upon hearing about this climate thingy were to question if a 4 metre sea level rise were already locked in by 2300, what sort of answer would he receive?

    I'm not being flippant, I'm directly asking if he would only receive waffle or would he be able to get a direct answer?

    This is what I mean by the communication breakdown arising from the fact sea-levels are not being communicated and thus engaged with. (Yes- I do have method!!)

  19. It's not bad

    ...and 'that' is bad!!

  20. It's not bad

    I hope I am not posting in the wrong thread, but: instead of aiming for a less than 2 degree rise in temperature shouldn't we be talking in terms of sea level rise?


    For instance I live on a hill and 5 metres isn't going to get to where I live but it will decimate the city and every supporting resource for the best part of 100 square kilometres, minimum!


    The answer could be quickly retorted that we don't know what kind of temperature that equates to and seeing as 2 degrees is a nice round figure that a population of billions can understand we'll go with that...


    Thus, the problem can now be seen as an inability to communicate at the most basic level making this a very bad problem indeed! Further, I am saying that the inability to respond to this basic communication problem will lead to panic when the problem becomes understood by the masses yet the lack of communication skills to be able to indicate that it has been appreciated and understood becomes the more pressing issue.

    .. I'm saying the important issue of the clear and present danger involved, i.e. a numerical value for sea level rise, is missing from the conversation!

  21. It hasn't warmed since 1998

    Tristan @302, it is not just the industry (or not just the industry).  Engineers (and doctors) are disproportionatly represented among creationists as well.  I think what happens is that the engineers are aware that they have a good technical education in areas that are closely related to science.  However, they are taught those skills as a recieved body of knowledge, so that they do not train themselves to not decieve themselves when it comes to science.  That leaves some engineers (and by no means all, or even most) prone to assume they can speak authoritatively on a subject that they do not understand.

    Nor should it be believed that this is a disease that only afflicts engineers, although the etiology is no doubt different for physicists:

    Finally, I agree with Glenn Tamblyn - engineers not afflicted with this peculiar arrogance do have the skills to understand climate science quickly and well.  They just have to be prepared to learn first. 

  22. It hasn't warmed since 1998

    I would imagine that the apparent increased incidence rate of denialism among engineers and geologists has less to do with the curriculum or knowledge base of those disciplines and more to do with the industry they often find themselves working within.

  23. The UK winter of 2014-15: another Tabloid FAIL

    Friends have pointed out that while I was writing this post, the nonsense continued apace:

    "Britain set for HOTTEST Easter EVER as temperatures to rocket to 80F in holiday heatwave" Express, 16th March 2015.

    "Easter weather forecast: TEN inches of snow, gales and plummeting temps - happy Easter" Express, 26th March 2015.

    And so it continues!

  24. Glenn Tamblyn at 16:47 PM on 27 March 2015
    It hasn't warmed since 1998

    Speaking as someone who did qualify as a Mechanical Engineer, I suppose I should step in to defend my profession. Mechanical Engineers, perhaps more than any other branch of engineering are actually uniquely qualified to evaluate climate science. So long as they are prepared to go back to their roots; to the core subjects they studied.

    Mech Engies don't just deal with gear trains and machinery. At it's core is a lot of study of thermodynamics, fluid mechanics, physics, maths etc. Other branches of engineering have a different balance. Electrical engineers don't do much fluid mechanics, Civil engineers don't do as much thermodynamics, etc.

    The problem for Mechanical engineers is that we tend to get channelled into dealing with machinery in our working lives and put the underlying core science we learn't on the back burner. If a Mech eng' can go back to their original training they have all the tools needed to assimilate climate science. As examples:

    • Heat Transfer - the Earth's Radiative Balance for example
    • Viscosity - how the wind imparts a shear force on the oceans and in turn shear forces within the oceans generate Ekman Transport.
  25. It hasn't warmed since 1998

    It saddens me to agree with one of the specific comments regarding engineers as having a poor grasp of science. I failed Mechanical engineering and basically can't have a considered opinion by default but do know this: Mechanical engineers are the most variedly paid engineers, presumably meaning some barely passed and possibly took decades to finish just for the status involved with such a title.

     I have talked to retired engineers who simply don't accept CO2 as being mechanically forced into the closed system called our atmostphere even though that is exactly what they were involved with doing all those years: truly weird, I must admit, but seemingly not an uncommon phenomenon.


    The well paid would never talk like this, would they?

  26. It hasn't warmed since 1998

    Albert H, you forget the possiblity of the ice sucking up the added heat content: it is my considered (lol, check me out: failed engineering student!!) opinion that the energy is going toward phase-change-mode.

    Politically the IPCC reports are by default conservative as all Governments involved have to agree as to what goes into them thus giving rise to my slightly panicked thoughts on this matter.

    The idea of 'diminishing returns' can be easily interpreted by the masses as wasted effort and the double-handling of matters tires us all. The need to Nip this problem of correlation with gap between rich and poor means climate denialism is over and the disinvestment campaign by the aroused consuming voter wins. What else is economics but a reason to get out of bed and do what needs to be done as the problem presents itself?

  27. Rob Honeycutt at 09:17 AM on 27 March 2015
    It hasn't warmed since 1998

    Albert H...  That might seem like a logical assumption, but with all due respect to your engineering experience, the assumption would be wrong. There's far more that you should endeavor to learn about ocean-atmosphere coupling before coming to any conclusions. Here is a good place to start: LINK

    There are also many great informative articles here on SkS that you should take the time to read through. Nearly all of the articles here are fully cited with the relative current research which, if you have further questions, you should locate and read through.

  28. It hasn't warmed since 1998

    Albert H, for the following I have used the Berkely Earth Surface Temperature (BEST) as I consider it the best currently available surface temperature index.  That is because it is constructed using (by far) more temperature records in determining the series than any other temperature index, and also constructed with a less controversial method than any other temperature index.

    Using the SkS trend calculator, I find the trends are as follows:

    1977-1997: 0.11 C per decade

    1999-2014: 0.121 C per decade

    I notice that the 1999 onward trend is slightly greater than the 1977-1997 trend.

    Of course, if I use 1998 for a terminal and initial year respectively, if find trends of 0.126 C per decade (1977-1998) and 0.09 C per decade (1998-2014).

    I will note first that that is not so large a difference as to justify your conclusion.  Your conclusion, therefore, is based on using an alternative, unspecified, and objectively inferior temperature index.

    More importantly, your conclusion is shown to follow primarilly from using 1998 as your bridge year.  1998, however, is an unusual year in that it was the year of the strongest or second strongest El Nino event on record.  (Its only rival occured at the same time as a major volcanic erruption, with the effects of the two events on temperature essentially cancelling each other out.)  1998's unusual warmth, on which your claim relies, is therefore a consequence of short term internal variability, not radiative forcing.

    Finally, the trend over the whole period was 0.164 C per decade, within error of model predictions.

    So much for the technical discussion.  I notice as an aside you claim to be an engineer with 40 years experience.  As such you would clearly know certain basic principles of data usage:

    1) You would know to use trends rather than end points in analysing rates to avoid "endpoint effects";

    2) You would know to use clearly identified sources of data;

    3) You would know to use the best available data, or at least to justify your choice when you do not; and

    4)  You would know not to cherry pick end points for data analysis.

    You have clearly violated each of these principles.  I am therefore forced to conclude that your claim to tenuous authority (engineers often have very bad understanding of science, together with an over inflated belief in their understanding of science) is false; or that you have deliberately violated good practise to strengthen a very weak argument.  Which is it?


  29. It hasn't warmed since 1998

    Albert, where are you getting your OHC figures?


  30. It hasn't warmed since 1998

    Hi. The year 1977 was the last year that the global temperature was ~the 20th century average of 13.9D C. - 21 years later, 1998 the gt was ~14.5. The 21st centruy average is so far 14.44D C. - 2005, 2010 and 2014 beat the 1998 temperature by a margin-total of just 0.1D C. -w/2014 being 14.6D C (warmest ever - with a measurement magin of error of 0.1D C ??)

    Today's rate of CO2 emissions has increased over the last century. The oceans of today that are "accumulating" heat existed back in the 20th century as well, yet the rate of change over 21 years was 0.6D C and the rate of change over the past 17 years (since) is only 0.1D C.

    2/3rds of the globe is ocean. Oceans are warming, per your statements, yet the 2/3rds of the planets atmosphere, above the oceans are only warming by 1/9th the rate, of previous warming.

    It would seem to this engineer in my 45th year as an engineer, that the atmosphere has reached a warming saturation and that all the heat trapping GHGs can't seem to provide any additiona warming in the atmosphere no matter how much the "plate" at our feet warms (accumulates) or how much CO2 enters the atmosphere.

    Something is not adding up. It would appear we need more heat-in to warm pass the curent highs we have been seeing. The highs can be beat by 0.01 or 0.03 degrees C but they will not increase by 0.6 without more heat input, it would seem.


  31. The UK winter of 2014-15: another Tabloid FAIL

    I'm glad I'm not the only one who notices these ridiculous predictions. You would really think that the "newspapers" - or their readers - would work out that these predictions are 100% wrong and cease and desist.

    I do remember the winter of '63 - I was 11 years old at the time and had just started secondary school. The snow seemed to last for ever and opposite my school the lake in Lister Park froze over.

    I also remember the winter of '71 when the River Cam froze in Cambridge. That has never happened since.

    I don't of course remember '47 but I have talked to people in the Cambridgeshire Fens who do - when the snow started to melt the pumping station at Tydd ran day and night for 2 months and they had to sandbag the doors to keep the water out. Upstream, there was catastrophic flooding when dykes broke across the Fens.

    Now those really were winters.

  32. The UK winter of 2014-15: another Tabloid FAIL

    Expect the same again next winter ..... :(

  33. So what did-in the dinosaurs? A murder mystery…

     Apology for unintended duplicate post above.

    In my quest of seeking confirmation on historical WARMING Data, I re-examined the Graph derived from Vostok, Antarctica Ice Core Data;
    which examined both Temperature levels, And, CO2 levels - vs TimeBP.

    The quantifications of the Climate Parameters (Temp levels and CO2 levels)
    are Not based on each other: rather, their levels are directly derived independently from each other - from the data measured in the ICE core.

    The cause of the obvious repeating and abrupt up and down cycles shown in the Vostok Ice Core are attributed to - as others here have advised me - Milankovitch Cycles - which in turn are all unconnected with, e.g., CO2.

    Taking a re-look at the Vostok Ice Core, what jumped out to me in looking at the two graphs (Temp and CO2) is that a Rise in Temps drives the Rise in CO2 - with the lag time of CO2 being somewhere in the vicinity of 800 years!

    One might quickly argue:

    "Then how do you explain the current parallel-in-time correlation
    of Rise in Temps - with Rise in CO2?"

    My response: 

    "IF as the Vostok graph clearly shows - Temps drive CO2 - and not the other way around, THEN, the current rises in CO2 would have to have been driven by rises in Temps 800 years ago.

    The only c.800 TimeBP rise in Temperature Anomaly that I can find which would correspond to the recent CO2 rise - is the Medieval Warm Period - previously mentioned by this website."

    Note: The CO2 ppm concentration is indicated by the pink graph


    Moderator Response:

    [PS] This is now completely offtopic. Take it here but read the article first before regurgitating a myth. 

  34. The UK winter of 2014-15: another Tabloid FAIL

    But they do, Wili! How do we get them to start reading Viz comic instead? Far funnier.

  35. So what did-in the dinosaurs? A murder mystery…

    This topic is "So what did-in the dinosaurs? A murder mystery…"

    The Moderator @56 stated that the discussion was far offtopic, which I disagree with, yet does not seem to think it is true here. Why not? 

    Moderator Response:

    [PS] I agree it is far offtopic and latest post from watchdog has been deleted.

  36. The cause of the greatest mass-extinctions of all? Pollution (Part 2)

    The diagram shows NOx emissions, but I see no mention of the ozone that results when NOx reacts to VOX and UV radiation.  As mentioned in the article, acid rain from sulpher dioxide, then and now, is more localized and not long lasting; however, ozone precursors travel in the troposphere and raise the background level of ozone globally.  It is highly toxic to vegetation according to countless research papers and governmental agencies including the US EPA - so I am curious why it isn't even considered here as a potential driver in the Permian extinction of plants and ultimately animals that rely upon them.  It is certainly a primary reason for current forest dieback:  

  37. So what did-in the dinosaurs? A murder mystery…

    CBD -  

    "CO2 certainly correlates with Temps."  — I say,  "Yes, it does."

    So do: SO2, Sky Darkenings, Volcanic Emissions, Crop Failures, Etc, 
    - correlate with Global Temps.

    Without anyone reverting to "CO2 levels" and only "CO2 levels",  
    I still await science data or data-generated graphs
    which quantify Temps (not CO2 levels) versus Dates
    which in turn show correlation with historical Mass Extinctions! 

  38. 2015 SkS Weekly News Roundup #13A

    Climate Central now has a piece devoted to the article on the slowdown of the AMOC.

  39. The UK winter of 2014-15: another Tabloid FAIL

    Isn't putting the word "fail" next to the word "tabloid" some kind of tautology or redundance or something??

    It's sad that anyone actually looks to these rags as sources of information.

  40. So what did-in the dinosaurs? A murder mystery…

    Watchkog, one of the primary suspected causes of "The Great Dying" (i.e. the P-T extinction event) is rapid CO2 increase/global warming. You will no doubt revert to, 'there are other theories!' again... but that is true about all of the 'evidence' you have been citing as well. Evidence about past events is often inconclusive.

    There is no question that rapid changes in atmospheric CO2 levels can cause corresponding rapid changes in global temperatures OR that such rapid temperature changes can cause extinctions. Further, there is very little question that such changes have occured in the past... only debate over which precise events were due to these vs other kinds of changes.

    One way to minimize uncertainty is to look at regional shifts in the more recent past... as you do with the 'Little Ice Age'. Taking the same approach for 'recent' warm events we find the collapse of the Chaco culture ~900 years ago, the Maya ~1200 year ago, the Khmer ~600 years ago, California the past three years, et cetera. Maybe next you'll say, 'those events were not all caused by rising CO2'... but that's irrelevant. The cold events you cite weren't all caused by the same factor either. You've conceded that "CO2 certainly correlates with Temps"... leaving your only apparent argument, 'warming does not cause extinction'... but there is overwhelming evidence to the contrary.

  41. So what did-in the dinosaurs? A murder mystery…


    The minor Cold Climate "blip" aka the Maunder Minimum, caused widespread Famine, and Forced Migrations of Peoples - including, forcing Vikings to abandon their colonies in the Land which became labeled "Green" due to the immediately prior Global Warming blip oft-referred to as, The Medieval Warming Anomaly.

    This Website discusses the Medieval Warming Period and its Causes. 

    How does the Medieval Warm Period compare to current global temperatures?

    " It has now become clear to scientists that the Medieval Warm Period occurred during a time which had higher than average solar radiation and less volcanic activity (both resulting in warming). "  

    Yes. Papers exist supporting its contention that: "warming would occur due to less volcanic activity resulting in higher solar radiation" - and I concur.  

    The article also presents a graph showing Temps surpassing the higher Temps of the MWP at some point in the 20th century due to AGW..



    So that I'm clear:
    I've never said: "Global Warming does not exist.
    Neither have I denied, "Periods of Global Cooling have existed".
    Nor have I denied, "Climate Change occurs with or without Man's input." 

    Please Show Me Temp Data - where Warmth Itself (which is "presented" as being predominately caused by its "predominate driver" - CO2, Yes? ) is the Climate- Parameter cause of Mass Extinctions? 

  42. keithpickering at 23:49 PM on 26 March 2015
    One satellite data set is underestimating global warming

    Please note that the datasets being compared here are for TMT, middle troposphere, and are NOT the TLT lower troposphere data generally used as a proxy for surface temperatures. 

    The issue identified here thus has no effect on surface temperature trends as measured from satellite (where UAH's trend is higher than RSS's trend). It does, however, affect the tropical troposheric "hot spot" at 10 km, which Dr. Roy has implied (based in part on his UAH TMT data) does not exist. 

  43. Glenn Tamblyn at 21:12 PM on 26 March 2015
    So what did-in the dinosaurs? A murder mystery…

    "CO2 is presented as being the cause of Global Warming."

    Umm... No It's Not!

    It is 'presented' as the most significant (but not only) driver of warming in our current context.

  44. One satellite data set is underestimating global warming

    How very interesting and informative.  

  45. So what did-in the dinosaurs? A murder mystery…


    "Earth's Temperature is oft-presented as being too Warm for the Biota."

    Citation for the above please.


    Mass extinctions are associated with rapid change - change too fast for adaptation. As other commentators have pointed out, change from cool to warm is indeed implicated in previous mass extinctions. Extinctions from change to cold (eg YD) are more controversial. The objection to the YD for megafauna extinction has been that it doesnt fit well with species that disappeared compared to those that survived.

    CO2 can be released very rapidly but it is harder to reduce it quickly so it is natural to look at its effects. Volcanism warms in long run - it only cools in very short term. 

    We dont blame climate change on CO2 because of correlation but from basic physics. If the sun suddenly put out an extra energy to tune 4W/m2 received at surface, then noone would be even slightly surprized at temperature change. Why the surprize when you get 4W/m2 from extra CO2 and a frantic search for alternative explanations?

  46. One satellite data set is underestimating global warming

    Thanks to both of you (Tom and Ian).  I understand the issue now . 

    Still, there is apparently  a different problem with RSS that has been publicized and even discussed by Spencer...  and the Trend calculator is going to leave people wondering about this (if they are using it as intended).    Since I "knew" that RSS was giving me lower readings than UAH based on the calculator and that it had a problem I also read with that bias making it harder to see the forest... too many trees.    

  47. New measurements confirm extra heating from our carbon dioxide

    jja @17, Feldman et al measured the surface radiative forcing of CO2.  The total surface radiative forcing will have been larger than that.  Therefore, for comparison I compared it with the radiative forcing of CO2.  The net TOA energy flux that you discuss includes the total forcing since 1750 from all sources, minus the increase in net upward energy flux due to increases in GMST including feedbacks on that temperature increase.

  48. So what did-in the dinosaurs? A murder mystery…

    KR@80 - My Apology for my sometimes opaque grammar. 

    No.. I am not saying CO2 causes Cooling

    Nor do I agree with this following:  
    "Long declines in CO2 causes Cooling."

    I am saying that Extended Periods of Extreme Cold
    are most definitely injurious to the Biota

    I am also saying that Blockages of Solar Radiation from e.g., Volcanism, 
    will directly cause Lowering of Temps. 

    With that above statement said, 
    I'm not saying that COLD is the only cause of injury to the Biota.

    Nor am I saying: Volcanism is the only cause of Lowered Solar Radiation.

    I am saying: Volcanism indeed reduces Solar Radiation / Temperature.

    Which brings me to CO2.

    CO2 certainly correlates with Temps
    - as does Black Carbon aka Soot, 
    - as does other Climatic parameters.

    Refer again to the Vostok Graph of Temp & CO2 @69
    and take close note of their correlation...

    CO2 is presented as being the cause of Global Warming.

    Which brings me to Global Warming

    Earth's Temperature is oft-presented as being too Warm for the Biota.

    I've several questions - and I'll begin with this one: 

    Has Warm Climate ever been the Cause of mass extinctions?

  49. One satellite data set is underestimating global warming

    If UAH (0.139C/dec) underestimates global warming, then RSS (0.122C/dec) underestimates it by even more.

  50. So what did-in the dinosaurs? A murder mystery…

    John Mason:

    More grist for the mill...

    Fact or Fiction?: Dark Matter Killed the Dinosaurs by Lee Billings, Scientific American, Mar 25, 2015

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