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Klapper at 12:01 PM on 21 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
@Skywatcher #14: You are right that the 60 year cycle has a limited data series to prove it out, at least from surface stations. However, if you think there is no 60 year cycle and that the PDO has no forcing ability, go look at Hansen's Figure 6(b) from his Jan.15 2013 report on the 2012 climate update. Look at the net forcing in the period 1910 to 1945. Pretty low isn't it? However, the warming rate from this period was pretty high. Where did this warming come from? The net forcing in Hansen's graph doesn't appear enough to drive warming rates of 0.12 to 0.16C/decade which is the range of the datasets. -
Klapper at 11:43 AM on 21 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
@Tom #13: Point 1) I tried to include the models which I had read were the best emulators of ENSO according to the Dessler comments. However, the model versions used then have been upgraded so I moved on guessing these same models might still be good at emulating ENSO. However, without resorting to watching for ENSO patterns, frame by frame in the monthly global map I can't make that call. However, neither can you. My guess is they do a poor job since ENSO is the primary source of short term variability and these models appear to have not so much as real data. Point 2) There are no volcanos including the the threshold trend of 0.043C/decade so this comment is irrelevant. Point 3) The forcing is definitely not constant, the change over cycle 23 was proably 0.1% to 0.14%. However the 15 year trend should smooth that out. Point 4) The recent papers by Foster & Rahmstorf et al don't include the suppressing effect of anthropogenic aerosols. You're throwing it on the table but can you quantify it? For the record all RCP scenarios have significantly decreasing sulphur over the 21st century (check the link at the bottom) so it is certainly less of a factor going forward. As for the comment on extending the trend, note that from 2080 on emissions decrease in RCP6.0, so it was legitimate to check if at the end of the period we might see some "standstill" trends. However, I did not find any, at least with the models I picked. Here's a link to the various emissions scenarios graphically displayed in CMIP5. https://tntcat.iiasa.ac.at:8743/RcpDb/dsd?Action=htmlpage&page=compare Just click the "+" buttons in column 3 and then one of the sub-options from the expanded menu, like "Total" to generate a graph. Very handy to compare scenarios. -
Klapper at 11:14 AM on 21 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
@Jason #10: I expect the models calculate global temperature "perfectly", that is the weighted surface air temperature by grid cell, by hour, day, month etc. Obviously no observation system in place, either satellite or surface station comes close to that temporal/spatial resolution. We have holes particularly in the Arctic and less so the Antarctic. Does that effect the capturing of natural variability and warming standstills? I don't know. The numbers are what they are. -
skywatcher at 10:40 AM on 21 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
#9 Klapper: My only additional comment (beyond Tom's excellent points; I hadn't thought of the difference in model forcing between early and later 21st Century) would be that it is dangerous to think of the PDO as a '60-year cycle'. In direct observations, we've had less than two periods of this "cycle", which appears significantly acyclical in that time, and longer palaeo studies such as MacDonald and Case (2005) don't show great evidence at all for a pervasive 60-year cycle in PDO. I'm in favour of hypotheses that the PDO is substantially an integrated product of ENSO variations. Certainly the PDO on its own is not apparently a strong global climate driver. To follow up on JasonB's point, using Hadley series as a comparison to models is risky as HADCRUT3/4 are not global teperature data - notably they miss out much of the Arctic, hence their trends will be underestimated with comparison to a model which is outputting global temperature estimates. In that case, GISS (which is global) may be closer to the mark for the past 15 years. -
John Hartz at 10:37 AM on 21 January 20132013 SkS Weekly Digest #3
vroomie: You're welcome and thank you for the positive feedback. PS - Dana actually composes the "SkS in the News" section each week. -
Tom Curtis at 10:26 AM on 21 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
edhawkins @11, Klapper has underestimated the probable frequency of such events because: 1) His sample of models do not all include ENSO mechanisms; 2) The forward model runs do not include volcanic events; 3) The forward model runs include a near constant, albeit low solar forcing; 4) The anthropogenic forcings (particularly aerosols) do not include significant fluctuations over periods of around 15 years; and 5) As he says, "My guess is these models for the most part don't really emulate ENSO very well", suggesting that even the models that incorporate ENSO dynamics understate potential variability in ENSO states. All five of these factors mean the individual model runs will tend to understate variability in 15 year trends, and hence his estimate from the models of a very low frequency of low 15 year trends. What is more, by extending his survey to 2100 on the model runs, he included a period with a significantly greater increase of forcing over time than is currently the case; and hence with a greater underlying trend. That again means his estimate is an underestimate of the probability of such a low 15 year trend at the start of the 21st century. Further, and more importantly, he does not estimate the probability of a low 15 year trend given a near maximum EL Nino state at the start of the 15 years and a near extended La Nina conditions at the end of it. Those two conditions make the probability of a low trend significantly greater than his estimate (or a more accurate, higher estimate if we could find one). All in all, Klapper's estimate is interesting only because it sets a ball park lower bound to the estimate of the probability of such a low trend. It certainly does nothing to suggest that the current low trend given known ENSO fluctuations was in anyway improbable. As noted before, in other analyses it has clearly been shown that the lack of such a low 15 year trend given the background anthropogenic trend plus known ENSO, solar and volcanic variations would be extraordinary. -
Tom Curtis at 10:06 AM on 21 January 2013CO2 is plant food
Soilfertility @14, your response has simply confirmed my point. First, you respond by quoting Albrecht from 1954, having previously made the point that "Albrecht did not address global warming as he was dead before global warming became an issue". If he did not address global warming, then he cannot have analysed which of two potential causes (global warming or loss of soil fertility) has had the greatest impact on changes in climatology. Ergo, if you are basing your claims on Albrechtson (as clearly you are), you have not shown of any particular droughts, floods, temperature rises, etc that loss of soil fertility rather than global warming is responsible. You specifically mention an article by Albrechtson titled "The Drought Myth--An Absence of Water is Not the Problem". Well, in Southwestern Australia an absence of water is clearly the problem:
What is missing in Southwestern Australia is water falling from the sky as frequently, something that is not under the control of soil fertility.
Southwestern Australia is a good test case, because the connection between winter rainfall and climate change is straightforward; there has been no appreciable loss of soil fertility (probably the opposite as agriculture in the region is based on irrigation turning desert into wheat fields); and Albrechtson almost certainly never studied the region. Yet because of his studies of the dustbowl you expect his explanation to trump straightforward science in Southwestern Australia.
I look forward to your evidence based proof that the decline in rainfall in Southwestern Australia is caused by declining soil fertility, or your acknowledgement that your assumption that any consequence predicted by both global warming and decreased soil fertility is explained by decreased soil fertility alone.
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vrooomie at 09:28 AM on 21 January 20132013 SkS Weekly Digest #3
Thanks, John....well-done. -
dagold at 08:38 AM on 21 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
As an interested lay person climate activist, there is something I am not 'getting' when following these conversations about 'hiatus periods': There is very little mention of the aerosal factor. ENSO is constantly discussed and solar variability is often mentioned. But...I have heard Kevin Anderson (in his now famous climate lecture) cite the (mostly) Asian aerosals as a HUGE temporary damping factor. And I believe (correct me if I am wrong), there is at least partial attribution to aerosals for the damping of the 1940-1970 period. So...what's up the scant mention of this element of the puzzle. Is it because there is a great deal of uncertainty and so better to leave it out? -
edhawkins at 05:19 AM on 21 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
@JasonB This is a good point, and not taken into account in this particular animation. I have discussed on my blog previously that it makes a small difference exactly how you do this type of comparison. ----------------- @Klapper Agreed that this type of slower trend is not especially common in these simulations (a few % as you suggest), but as there are many 15 year (overlapping) trends it is almost inevitable that we get one or more.Moderator Response: [PW]Hot-linked URL. -
JasonB at 01:57 AM on 21 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
The last 15 years of actual climate are reported as 0.043 °C/decade for HadCRUT4, 0.074 °C/decade for GISTEMP, and 0.036 °C/decade for NOAA, because each uses a different method to calculate the global temperature anomaly. I'm curious to know how the CMIP5 model run temperature anomaly is calculated? I had a quick search but couldn't find an answer. If you're comparing the last 15 years with model runs, you need to make sure that they're being calculated the same way (i.e. that the figure is what e.g. HadCRUT4 would have reported if that simulation exactly matched the real world) to have an apples-to-apples comparison. -
Soilfertility at 01:00 AM on 21 January 2013CO2 is plant food
Hi Tom: Your assumption that my argument "fails at that point" is unjustified. Why? You have failed to review Albrecht's evidence. If you would only have read the article I mentioned on "The Bovine", it would have directed you to Albrecht's article, the basis for the article on "The Bovine". Albrecht's article, titled "Droughts-- The Soil As Reasons For Them", is chapter 23 in Volume I of "The Albrecht Papers". This is the first paragraph from his article: "When one follows the meteorological reports rather regularly since most of us talk about the weather, at least when the radio reports it for us daily, one might well be asking with serious concern, 'How come that we keep on breaking flood records, heat records, past records for droughts or for extent of long-time rain free periods and other weather records?' Are the meteorological conditions changing for the worse, or are the biological manifestations of weather, labeled as drought, merely intensified and on the increase as reciprocal to some other factor under serious decline through which the same meteorological disturbances are magnified in their detrimental aspects? We have larger floods and we have more severe droughts as the records truly report. But should we not examine these in relation to the soil for possibly more comprehensive explanations of them and our reduction or prevention of the disasters?" From the introduction to the chapter: "This paper was read before the 11th Annual Meeting of the American Institute of Dental Medicine, Palm Springs, California, 1954." "The Albrecht Papers" Volume I has been reprinted and is now titled, "Albrecht's Foundation Concepts" and is available from Acres, U.S.A. Also at Acres, U.S.A. there is an article available for download by Albrecht titled, "The Drought Myth--An Absence of Water is Not the Problem. It is available in this list of articles- http://www.acresusa.com/toolbox/articles.htm -
Klapper at 18:27 PM on 20 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
Skywatcher @#8 The solar irradiance input to the CMIP5 model runs is based on repeating cycle 23 (1996 to 2008) going forward. Or at least that is the recommended input. Cycle 23 is a pretty long cycle, longer than the typical 11 years. If you've looked at Hansens Figure 6(a) from his 2012 update, published Jan. 15, you can see he gives very low input to solar irradiance changes. In his text he states that recent declines in the irradiance trend may have decreased the irradiance forcing by 0.1W/m2. However, he doesn't specify the time period this has occurred over. As for the ENSO trend you are right, depending on how you define "recent". It looked the same about 1975. This could be used to support the argument that ENSO trends, rather than being just random noise supperimposed on a warming signal, follow patterns that are not random and are tied to the 60 year PDO cycle. -
skywatcher at 17:19 PM on 20 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
This is a very nice graphic - another excellent illustration to support the Escalator and Kevin C's recent animation. Klapper, without going into your point in too much detail... how do the model runs you selected handle solar activity? One of the noticeable features of the past decade and a bit has been the fairly remarkable transition from a pretty active to a pretty quiet Sun. In conjunction with a 15-year trend in ENSO that is unmatched in the recent record (linear trend in bimonthly MEI data leans unusually far from horizontal), the potential for an unusual illusory slowdown in warming has been exceptional. With just ENSO, the conditions of the past decade and a half have been unusual. Adding the unusual pattern of solar activity has made the short-term trend even more weird, yet GHG forcing has continued unabated. Unfortunately for us, neither the solar activity nor the ENSO can go a huge amount lower (notwithstanding very strange low solar activity), and so the GHG-driven warming trend will inevitably dominate once more, aided by the equally inevitable neutralisation of the negative trends in solar and ENSO activity. -
Klapper at 16:35 PM on 20 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
Tom @#4: Your questions on El Nino can't be answered from the data I used, which was a simple global monthly surface ari temperature anomaly series. However I can comment on the nature of the deviations in the AOCGCM models. Two models had no 15 year trends below .07C/decade (GISS and GFDL). Of the 3 remaining, MRI only had 4 months where the rolling 15 year linear regression trend dropped below the threshold, and not consecutively, mostly at the end of the period (near 2050). The two models which made up the bulk of the "standstill" trends, CSIRO and Hadley, had these sub-threshold trends come all in one continuous period, both around 2030. My guess is these models for the most part don't really emulate ENSO very well. I also checked the period from 2050 to 2100. None of the models show any months with a 15 year trend below the threshold of 0.043C/decade. Note that the CMIP5 RCP6.0 scenario is the least aggressive for CO2 emissions growth in the early part of the forecast. In fact under this scenario there is no emissions output growth between 2010 and 2030, which is probably not realistic. However, after 2040 RCP6.0 surpasses emissions growth compared to the scenarios RCP4.5 and RCP2.6, peaking in 2080 or so. -
noelfuller at 16:20 PM on 20 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
Actually Tom, getting a handle on short term variability might enable closure of the gap between the long term trend prediction and the short term weather stuff. If we can put the natural variability into the climate context we are in a better position to explain what is going on and make predictions of value to growers and planners so it is not entirely uninteresting - if the greater context is always there. -
noelfuller at 15:40 PM on 20 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
I fancy you might enjoy my lurching Bedford analogy based on Hansens use of the term standstill. Of course it can't be taken too far: When learning to drive I was one afternoon given the wheel of a 2 ton Bedford truck with an unbaffled tank of water on the back and instructed to drive it from Napier to Taradale. As I pulled out the water surged backwards, then forwards and so forth resulting in an uneven motion of the truck which I struggled to get control of. Ahead was a major intersection. A vehicle was approaching from the right. I clapped on the brakes but nosed onto the inersection with the water slopping forward over the cab. The car having dodged the truck, I tried to keep going but the wave was heading aft. The truck remained almost at a standstill with more traffic coming in all directions – then the wave started forward again with my foot still on the accelerator and the impulse of the wave, the truck rocketed across the remainder of the intersection to the surprise and consternation no doubt of the oncoming drivers. Eventually I got the hang of it. So if we label the wave in the tank ‘ENSO’, the road toward Taradale ‘Climate Change’ and paint ‘Rising Global Surface Temperature’ on the truck we have it. The wave in the forward direction is El Niño, the wave going aft La Niña. Perhaps the engine could be labeled ‘Fossil fuel Combustion’ and the exhaust ‘GHGs’. Hmm, what about the driver? – new video animation for skeptical Science? -
Doug Hutcheson at 13:55 PM on 20 January 2013CO2 is plant food
Soilfertility @ 11, I am still puzzled by your comments. Where in points 1,3,4,5 and 6 in the list, is there a scientific error? You are the one asserting there has been a scientific mistake. No-one is disputing the rôle of soil impoverishment on plant growth. Exactly what error(s) are you claiming? -
Tom Curtis at 13:37 PM on 20 January 2013CO2 is plant food
Soilfertility @11, you introduced your original comment by saying, "... consequences of declining soil fertility are incorrectly said to be caused by global warming." Your evidence of this is that certain predicted consequences of global warming are also predicted consequences of reduced soil fertility. You proceed to make the unjustified assumption that any observed feature that is predicted as a consequence of both global warming and of decreased soil fertility is in fact only a consequence of reduced soil fertility. Your argument fails at that point. Your assumption is unjustified. It appears to be worse, however. You point out that decreased soil fertility can result in increased floods and drought due to, respectively increased water runoff, and decreased water retention. You then simply assume the increased floods and droughts actually experienced are due to reduced soil fertility without providing evidence of that reduces soil fertility at the locations of said floods and droughts, or even checking rainfall figures to see if they have changed over time (they have). So not only do you assume that decreased soil fertility is the proper explanation without examining the evidence, you do so even when it is against the evidence. -
Tom Curtis at 12:58 PM on 20 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
Klapper @3, what percentage of 15 year trends cherry picked to have a record breaking EL Nino event in the start year had low trends? And what percentage cherry picked to stradle a record breaking El Nino at the start, and two very strong La Nina events at the end of the record? And why do we care about cherry picked short term trends when it has been repeatedly shown by different methods that once allowance is made for ENSO influences on temperature, the underlying trend continues unabated? The simple fact is that 15 year trends in temperature are scientifically uninteresting - but they sure make good politics. -
Soilfertility at 12:17 PM on 20 January 2013CO2 is plant food
Hi Doug: I was commenting on numbers 1,3,4,5 and 6 in the list of "...the effects of an increase of CO2 on agriculture and plant growth in general". I was not commenting on any topic on this thread. I thought comments were invited to made on the article itself. In the article I wrote for "The Bovine" titled, "Albrecht on Droughts and Soil Fertility" I have included references to where in Albrecht's papers I came across the evidence. I am not going to retype that article here. If you have any interest whatsoever in challenging the evidence provided by Albrecht you might just go and read the article and then tell me where I am wrong. Ignoring evidence does not refute it. I don't know the name of the person who wrote this article but the person's lack of knowledge of the consequences of declining soil fertility has resulted in the mistake of blaming more carbon dioxide in the air for consequences that are actually caused by declining soil fertility. In conditions of higher soil fertility there would be no need to plant trees and trees would grow better free from insect and disease problems and they would thereby do a better job of removing carbon dioxide from the air and they would make better firewood. If you knew that agriculture produces food for yield at the expense of its nutritional value, would you be concerned? If you would be concerned about this, that would give you another reason to wade through Albrecht's papers which would serve you better than wading through any post of mine. -
Klapper at 11:39 AM on 20 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
In the model world, how rare are months where the previous 15 year trend is less than 0.043C/decade, the current 15 year linear regression? To find out I downloaded a number of runs from CMIP5 for the same scenario used above(RCP6.0)for the parameter SAT. To start I chose the 3 "best" models for simulating ENSO according to Dessler 2011 (MPI, MRI and GFDL). However MPI didn't have a RCP6.0 run (yet) and I needed a better representation than just 3 models. So I added the model used in this post (CSIRO) plus 2 more from prominent institutions (GISS and Hadley). That gave me 5 model runs, not a lot but a start. Where there were multiple runs under RCP6.0, I used a random individual run. Source of the data was the KNMI Climate Explorer website. I ran a 15 year rolling linear regression by month for all 5 runs and found that 3.4% of months had a 15 year linear trend of less than 0.043C/decade, the current number. I used 15 years since that's what the graph above used (1998 to now). So while temperature growth "stand-stills" do happen in the model world they are certainly not common. -
Doug Hutcheson at 10:49 AM on 20 January 2013CO2 is plant food
Soilfertility @ 9, you saidI have come to the conclusion that blaming consequences of declining soil fertility on global warming is a scientific mistake
I asked you for evidence that scientists have made such a mistake, but you have not produced any. Who, exactly, is making this "scientific mistake"? Where is your evidence? Without support for your allegation, it appears you have constructed a strawman argument. I am sure Albrecht makes some interesting points about soil fertility, but what precisely is the connection with the topic of this thread? -
Bob Loblaw at 10:18 AM on 20 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
Yes. I wonder if some of the people that think that the recent (non-significant) observational "trends" are meaningful also think that there are "unknown factors" causing "pauses" in the simulations, too. -
Albatross at 09:02 AM on 20 January 2013Ed Hawkins: Hiatus Decades are Compatible with Global Warming
Now that is a great animated gif by Ed Hawkins, and it really illustrates the problem of cherry picking short windows of time and then making misleading claims about what they suggest for the future. Hey look, there are multiple "slowdowns"/plateaus in the future too, that must be good news for those in denial ;) They can be playing this game of seeking out stalls and claiming AGW has ended many decades from now. PS: My guess estimate was that the blue trace would, in the short term, exceed the red trace but that was wrong. -
DSL at 08:10 AM on 20 January 201316 ^ more years of global warming
Isn't there a paper on the "shift" in the AMO-GST relationship post 1960? You can see the emergence of the GW signal in the development of the lag between GST and AMO post 1960. Or am I hallucinating publications? -
DSL at 08:05 AM on 20 January 20132012 Shatters the US Temperature Record. Fox, Watts, and Spencer Respond by Denying Reality
Oh, come on DB! The entertainment value . . . sigh. Maybe we should have a deleted comments thread--one that doesn't get aggregated into the "all comments" stream.Moderator Response: [DB] Patience. Such a thing is in development. -
Dikran Marsupial at 04:28 AM on 20 January 201316 ^ more years of global warming
@curiousd/ianC Tamino discussed AMO here, and makes the point that AMO may be the effect rather than the cause. -
IanC at 04:07 AM on 20 January 201316 ^ more years of global warming
curiousd, An issue with their analysis, IMO, is that the AMO index used is based on the North Atlantic sea surface temperature, which is not surprisingly highly correlated with global temperature change:
Even though the AMO index is constructed by detrending the north atlantic SST, it is very likely that the nonlinear component of global warming signal is still embedded in the index. The issue is that when you use the AMO index as a regressor, you are potentially trying to use part of global temperature to explain global temperature, which exaggerates the role of the AMO.
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Klaus Flemløse at 03:43 AM on 20 January 2013Accumulated Cyclone Energy Questions and Answers
It has been positive to read R. N. Maue's blog with easy access to data. However, I am somewhat surprised to read one of his conclusions of his paper, namely that R. N. Maue:“Additionally, the global frequency of tropical cyclones has reached a historical low”. Considering the fact that the tropical storms have only a small impact on ACE – approx. 12 %? - and it is common knowledge among climate scientists that the proportion of Major Hurricanes is growing, it is difficult to understand why R. N. Maue reaches his conclusion. He ought to have concluded: “The number of Tropical Storms has according to my analysis and in line with IPCC been decreasing and Major Hurricanes increasing. It is a paradox that we have not seen an increasing ACE.” Remember that scientists love paradoxes. Therefore R.N. Maue ought to be happy that I have appointed a paradox to him. -
citizenschallenge at 03:29 AM on 20 January 2013Accumulated Cyclone Energy Questions and Answers
And how does the Power Dissipation Index (PDI) fit into this? Atlantic tropical cyclone (hurricane) activity, as measured by both frequency and the Power Dissipation Index (which combines storm intensity, duration, and frequency) has increased. ~ ~ ~ ~ ~ ~ ~ And for discussion sake there's this: https://ams.confex.com/ams/90annual/techprogram/paper_165391.htm 18th Conference on Applied Climatology (5B.5) The misuse and misinterpretation of the ACE and PDI indices for hurricane energetics Angela M. Fritz, Georgia Institute of Technology, Atlanta, GA; and J. I. Belanger, J. A. Curry, and G. J. Holland "The Accumulated Cyclone Energy (ACE) index and the Power Dissipation (PDI) Index are widely used as metrics to quantify seasonal hurricane activity both in the Atlantic basin and worldwide. It can be shown that both of these indices are based on inaccurate assumptions that lead to a misuse and misinterpretation of the resulting index. Towards advancing the indices of hurricane energetics that are associated with potential damage, we develop a new methodology for calculating an integrated kinetic energy (IKE) climatology. A simple, observation and dynamical – based radial wind speed model is used with the Extended Best Track dataset to calculate IKE for North Atlantic Hurricanes from 1988 to 2008. The method is evaluated against previous methods of tropical cyclone intensity analysis, and the results are compared to traditionally misinterpreted indices in terms of characterizing storm energetics and relating it to storm surge. It is shown that the traditional indices are inaccurate measurements of hurricane energetics, and the assumptions that they are based on are not valid." Session 5B, Topics in Applied Climatology II Tuesday, 19 January 2010, 1:30 PM-3:00 PM, B212 -
JoeT at 03:17 AM on 20 January 20132013 SkS Weekly News Roundup #3
Thank you for putting together this round-up. I always find something interesting to learn. One thing I would point out --- in the article titled "Megadrought took long-lasting toll on Amazon rainforest" there is this quote from Sassan Saatchi, of NASA's Jet Propulsion Laboratory, the lead author of the paper: "Our results suggest that if droughts continue at five- to 10-year intervals or increase in frequency due to climate change, large areas of the Amazon forest are likely to be exposed to persistent effects of droughts and corresponding slow forest recovery," Saatchi said. "This may alter the structure and function of Amazonian rainforest ecosystems." I would point out that Ranga Myneni is a co-author on the paper. Myneni is the guy who Matt Ridley quotes in his Wall Street Journal article as saying that the increasing greening of the planet is half due to increased warming or rainfall and half due to carbon fertilization. All the more reason for someone to check with Myneni and see if his views were represented accurately. -
Philippe Chantreau at 02:15 AM on 20 January 20132012 Shatters the US Temperature Record. Fox, Watts, and Spencer Respond by Denying Reality
I perused through Backslider's posts and I did not see a single real scientific reference. Plenty of rethoric with words such as "very", "unscientific", "qualified" and what not. No analysis, no peer-reviewed paper, nothing. How am I to take it seriously? I'll add that arguing Urban Heat Island when the temp records are across the entire country is a rather amusing stand. Ironic that this happens on a thread about denying reality. -
citizenschallenge at 02:08 AM on 20 January 2013Accumulated Cyclone Energy Questions and Answers
It would be interesting if a future update of this post included a comparison of the strengths and weaknesses of these two metrics and what they tell us. ~ ~ ~ ~ ~ ~ ~ Alternative Metrics of Tropical Cyclone Impact http://www.aoml.noaa.gov/hrd/ike/ Tropical cyclone damage potential, as currently defined by the Saffir-Simpson scale and the maximum sustained surface wind speed in the storm, fails to consider the area impact of winds likely to force surge and waves or cause particular levels of damage. Integrated kinetic energy represents a framework that captures the physical process of ocean surface stress forcing waves and surge while also taking into account structural wind loading and the spatial coverage of the wind. Integrated kinetic energy is computed from gridded, objectively analyzed surface wind fields of hurricanes now available in near real-time from the H*Wind web page http://www.aoml.noaa.gov/hrd/data_sub/wind.html ~ ~ ~ 11/02/2012 Superstorm Sandy packed more total energy than Hurricane Katrina at landfall By Brian McNoldy ~ ~ ~ -
curiousd at 01:49 AM on 20 January 201316 ^ more years of global warming
Technical Question on Zhou and Tung, J. Atm, Sci. vol 70, Jan 2013 pp. 3-8. Quite on topic, just out to academic libraries.. They do a regression analysis including the AMO and find this addition strongly reduces the rate at which the temp increases due to GHG. But they have data all the way back to 1850 and try only fits that are linear with time. Why should one even expect the GHG contribution is linear with time, especially over this long a time period? See their Fig. 4 to see problems that arise. If driven by CO2 temp increase is linear with respect to log to base two of COs concentration ratio, not linear with time and the difference will be pronounced if you go back to 1850. In my figure in comment 47 above, I get a good fit with a c.s. of 2.035 plus or minus .074. We should have, perhaps, a discussion about the Zhou and Tung paper. -
Bernard J. at 01:40 AM on 20 January 20132012 Shatters the US Temperature Record. Fox, Watts, and Spencer Respond by Denying Reality
Backslider at #34:I might also remind you Tom that climate events do not constitute climate change.
Even with the most generous of concessions, this is not true. A single climate event, if sufficiently extreme, can indicate a change in climate by simple fact of the nature of its extremity. And a particular trend in the nature of "climate events" can certainly "constitute" climate change. At #42:In my very logical opinion, a Stevenson box is the most unscientific contraption ever invented. I don't actually accept any of their readings as being close to accurate.
With due respect, there is little that resembles logic in your opinion. 1) Stevenson invented the screen in 1864, and it was introduced into Australia in the 1880s, with almost universal use by the first decade of the 20th century. Therefore the use of the screen was prevalent before any appreciable signal from human-caused global warming. 2) Even if there was a warming bias resulting from a Stevenson screen (and as Albatross notes at #46 the bias is actually in the opposite direction), the nature of the bias in the temperature record would be consistent across time. And as the use of Stevenson screens pre-dates global warming, there is no change in the nature of the temperature record resulting from any bias - and certainly not in a warming direction. You may not accept the data obtained from Stevenson screens as "being close to accurate", but the data do not have any regard for your opinion. Even if a bias exists it is systematic, rendering your protestation moot. Interesting churning of a denialist meme though - I was unaware of this particular nonsense from Watts and Codling until you dragged it here. -
sauerj at 00:02 AM on 20 January 2013Skeptical Science and social media - Ask not what SkS can do for you, but what you can do for SkS
I've put key graphs on my FB "Cover". I think this is a good way to advertise to friends key persuasive information. When they mouse over your profile picture, they will see this cover picture pop up. I've had one image in place now for several months; it would be better if I rotated through different pictures so to keep interest up. But, one issue is that to effectively show the whole picture requires cropping and re-sizing the image to 712(W)x260(H) pixels. This is a very wide & squatty image. This doesn't work for most of the graphs and yet still show a proportionally sized image. Not asking for a lot of work to issue 2nd set of images, but just laying this out as something to think about when generating these images. -
Soilfertility at 21:01 PM on 19 January 2013CO2 is plant food
Hi Doug: I said that I have come to the conclusion that blaming consequences of declining soil fertility on global warming is a scientific mistake. I did not say that any scientist has ever written a scientific paper blaming the consequences of declining soil fertility on global warming. I am not aware of any global warming research scientist who has knowledge of the consequences of declining soil fertility that would allow his or her writing of such an paper. What lead to my coming to that conclusion was, as I suggested at the end of my post answering the question I posed, was my reading of papers left by the late soil scientist, William A. Albrecht, Ph.D. In his papers, Albrecht explains many consequences of declining soil fertility. Albrecht did not address global warming as he was dead before global warming became an issue. Around the middle of the last century, Albrecht explained how declining soil fertility was increasing the severity of weather hazards such as floods and droughts. He also explained that the soil fertility controls the erosion of the soil itself with lower soil fertility being the primary cause, not the wind or rain. With respect to CO2, the subject of the article above, he explains how the carbon dioxide dissolving in the rain creates a weak carbonic acid that is beneficial in increasing soil fertility by breaking positive ions necessary for life (such as calcium, magnesium and potassium) out of rocks that contain these elements when such rocks are still in the soil. This certainly suggests how to restore or increase soil fertility when parent rocks containing these minerals have been exhausted from the soil and soil fertility is necessarily declining. If you wish to read an article I wrote I titled "Albrecht on Droughts and Soil Fertility" you can read it here: http://thebovine.wordpress.com/2012/08/11/droughts-and-soil-fertility/ Hopefully it might inspire you to wade through Albrecht's papers which I think will serve you better than wading through a post of mine. -
skywatcher at 20:39 PM on 19 January 20132012 Shatters the US Temperature Record. Fox, Watts, and Spencer Respond by Denying Reality
Well worth noting the utter lack of support for Backslider's claims, especially the allegations of impropriety made in the second paragraph of #42. In science, Backslider, we require evidence. You don't appear to have anything but your incredulity. A more measured take on Australia's heatwave comes from this informative article in The Conversation, written by the BoM, and published the morning before Sydney broke it's all-time high temperature record. Particular attention might be drawn to the ratio of high to low temperature records, and the ratio of night-time to daytime temperature records, consistent with the expected effect of an enhanced greenhouse effect. Others can probably highlight the links to studies showing how rural stations also show warming and are an integrl part of temperature monitoring. I'd like to draw attention to measures that cannot be attributed to UHI - the near-universal retreat of mountain glaciers, the melt in Arctic sea ice, the temperature of the lower troposphere, and the shifting poleward of species. The tough truth is, when conditions are right, heat records are much, much more likely to fall than cold records in our warming world. -
Doug Hutcheson at 16:51 PM on 19 January 2013Skeptical Science and social media - Ask not what SkS can do for you, but what you can do for SkS
Excellent, John. Puts things handy for quick reference. -
John Cook at 16:48 PM on 19 January 2013Skeptical Science and social media - Ask not what SkS can do for you, but what you can do for SkS
Note: I've just added icons in the SkS left margin linking to our YouTube channel and Pinterest page. -
Albatross at 16:05 PM on 19 January 20132012 Shatters the US Temperature Record. Fox, Watts, and Spencer Respond by Denying Reality
Regarding the outrageous (and unsupported claim) made by poster "backslider" about Stevenson screens. The fact of the matter is that, if anything, Stevenson screens have a slight cool bias when compared against the reference instruments. From a World Meteorological Organization report. (conducted in Australia as it happens): "It has been recognised since the early part of the century (Koppen 1913) that the Stevenson screen impacts significantly on the temperature measured. Its large thermal mass results in a large thermal lag and as a consequence underestimates the maximum and minimum temperature. Despite this it remains a useful screen." Other field tests have made similar findings, see here for example. Stevenson screens are not the problem here, it is some people's ignorance and denial about global warming that is the real problem. -
Tom Curtis at 15:55 PM on 19 January 20132012 Shatters the US Temperature Record. Fox, Watts, and Spencer Respond by Denying Reality
Backslider @41:"We have records since the first fleet in fact, kept by reputable scientists using well calibrated equipment and a far more sane method of measuring which is totally at odds with a Stevenson hot box."
My, the joys of being a Sydney-sider and imagining that Sydney is all of Australia. Anyway, more importantly, name these "reputable scientists" and their scientific qualifications. You will in fact find that they are, in the early period, army or navy officers with a pro-forma interest in accurate temperature records using instruments of far inferior quality to those today."Try sitting in your car in forty degree heat with the windows down - that's what a Stevenson box is like."
Do you even know what a Stevenson Screen is? They are double louvred on all sides so that there is no impediment to passing breezes, and no possibility of accumulating heat through restricted convection. The proper comparison is sitting under an extensive wooden roof guaranteeing full shade but not restricting any air flow. I tire of you now. You have done nothing but regurgitate talking points from Jonova without any apparent understanding of what you are talking about. What is more, you are demonstratably making up claims to bolster your case with no knowledge of the relevant facts ("respected scientists", "explorers ... were scientists"). You are adding nothing useful this conversation except for those with a taste for the absurd. -
Tom Curtis at 15:42 PM on 19 January 20132012 Shatters the US Temperature Record. Fox, Watts, and Spencer Respond by Denying Reality
Backslider @37: 1) You may not be able to get your head out of Sydney, but the rest of Australia can. We (those Australian's outside of Sydney) are talking about a heat wave not because of two very hot days in Sydney, but because of 46 individual maximum temperature records in Australia so far in 2013; and because of repeated Australian mean maximum temperatures at or near record levels. 2) The early explorers were not scientists, but ex-Navy or Army officers like Charles Sturt and Burke with the occasional surveyor like Wills. (And for non-Australian's, please read up on the Burke and Wills expedition to see just how absurd is this suggestion that because records were taken by explorers, they were taken with unusual competence.) Charles Sturt was, of course, very competent, but the suggestion that measurements made on thermometers packed and carried very day, then set up in an ad hoc fashion in tents or in the partial shade provided by eucalypt trees, and at an unknown distance from the ground should be more accurate than that provided by Stevenson Screened instruments is absurd. 3) I do not have to make a comparison between Stevenson Screened instruments and others. It has already been done:"In view of the implications for the assessment of climatic changes since the mid-nineteenth century, systematic changes of exposure of thermometers at land stations are reviewed. Particular emphasis is laid on changes of exposure during the late nineteenth and early twentieth century when shelters often differed considerably from the Stevenson screens, and variants thereof, which have been prevalent during the past few decades. It is concluded that little overall bias in land surface air temperature has accumulated since the late nineteenth century: however, the earliest extratropical data may have been biased typically 0.2°C warm in summer and by day, and similarly cold in winter and by night, relative to modern observations. Furthermore, there is likely to have been a warm bias in the tropics in the early twentieth century: this bias, implied by comparisons between Stevenson screens and the tropical sheds then in use, is confirmed by comparisons between coastal land surface air temperatures and nearby marine surface temperatures, and was probably of the order of 0.2°C."
See also here for comparisons between modern methods. I also know, as you obviously do not, that temperatures taken in the shade in poorly ventilated locations locations, or unusually close to the ground can exceed temperatures recorded in Stevenson Screens by up to ten or 15 degrees. That is why it is now law in Australia that you are not permitted to leave unattended children in parked cars. Poor house design in outback and subtropical Australia can easily result in internal temperatures several degrees above that found in neigbouring Stevenson Screened instruments, as indeed can internal temperatures in tents, particularly tents lacking a fly. @38, living in Mount Isa, I know from personal experience that the numbers of birds described as dying are way in excess of the carrying capacity of the land they are described as dying in. I also know that hyperbole is a favoured technique in Australian story telling. You do the maths. So many birds they snapped the branches of the trees, according to one account. Which makes a good yarn, and a better one when some (--snipped--) can't recognize when a yarn is being spun.Moderator Response: (Rob P) Inflammatory snipped. -
Backslider at 15:38 PM on 19 January 20132012 Shatters the US Temperature Record. Fox, Watts, and Spencer Respond by Denying Reality
And yes JasonB, the equipment., even from the 1700's has been acknowledged as very accurate by very real modern day scientists..... -
Backslider at 15:30 PM on 19 January 20132012 Shatters the US Temperature Record. Fox, Watts, and Spencer Respond by Denying Reality
@Jason - Let me be clear. In my very logical opinion, a Stevenson box is the most unscientific contraption ever invented. I don't actually accept any of their readings as being close to accurate. The biggest flaw with modern climatology is all the unscientific generalisation and adjustments being made, which ultimately are based only upon opinion. "Oh yes, I think we should deduct a degree or two here and perhaps add a couple over there". That, in truth, is what we have. A far better measure is to collate records only from areas that have not subsequently become urbanised. Then we would have a far clearer picture of the true situation. Then we would havesomething that I could regard as perhaps a little closer to scientific (except for Stevenson screens). Alas, we do not have that. -
Backslider at 15:24 PM on 19 January 20132012 Shatters the US Temperature Record. Fox, Watts, and Spencer Respond by Denying Reality
@JasonB - Exactly where have I said that old temperature records are suspect? Or do you think that your "scientific" generalisation fits just because you want it to? Old records show global warming do they?.... I don't think so. They show a far hotter Australia way back in the 1700's -
Backslider at 15:22 PM on 19 January 20132012 Shatters the US Temperature Record. Fox, Watts, and Spencer Respond by Denying Reality
"the first time that has happened since record keeping began in 1910" Since record keeping accepted by you began you mean. We have records since the first fleet in fact, kept by reputable scientists using well calibrated equipment and a far more sane method of measuring which is totally at odds with a Stevenson hot box. Try sitting in your car in forty degree heat with the windows down - that's what a Stevenson box is like. -
Doug Hutcheson at 15:20 PM on 19 January 2013CO2 is plant food
Soilfertility @ 7, After wading through your post, I find you saidblaming consequences of declining soil fertility on global warming is a scientific mistake
Excuse my ignorance, but exactly which scientific papers are you referring to? I cannot recall ever hearing a scientist blame 'consequences of declining soil fertility on global warming'. It sounds suspiciously like a strawman argument to me. -
JasonB at 15:14 PM on 19 January 20132012 Shatters the US Temperature Record. Fox, Watts, and Spencer Respond by Denying Reality
It's funny how old temperature records are considered suspect when they show warming, but are made by "scientists, using calibrated equipment which has been acknowledged as accurate" when they show high temperatures in the past. Anyway, my favourite is Darwin and the change that happened during WWII. :-)
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