Monthly Archives: August 2010

Meeting September 7-9 2010 “Surface Temperature Datasets For The 21st Century” Chaired By Peter Thorne

There is a meeting scheduled September 7-9 2010 in the United Kingdom in Exeter titled

Surface temperature datasets for the 21st Century

This meeting has a set of white papers to frame the meeting.

However, at the very start of the meeting, it presents the bias of the organizers of this meeting as they write

“To meet 21st Century requirements it is necessary to reconsider our analyses of historical land surface temperature changes. This is about much more than simply re-engineering existing datasets. These datasets were adequate for assessing whether climate was changing at the global scale. This current exercise should not be interpreted as a fundamental questioning of these previous efforts. But these pre-existing datasets cannot answer all the questions that society is now quite rightly asking. They do not constitute a sufficiently large sample to truly understand our uncertainty at regional scales. At monthly resolution they are also of limited utility in characterising extremes in climate and their changes.”

The  statement that “These datasets were adequate for assessing whether climate was changing at the global scale“, yet “They do not constitute a sufficiently large sample to truly understand our uncertainty at regional scales” is scientifically flawed. The global average trends are composed of the summation of the regional trends!  The data cannot be adequate on the global scale (as an average) but not on the regional scale.

While, we need to wait to see what they actually accomplish at this meeting, the above statement indicates the organizers are persisting in assuming any regional variations are random and that a clear signal emerges when the surface temperature data are globally averaged.  More generally, they appear to be ignoring research that conflicts with their findings.

The Chair of the organizing committee is Peter Thorne and the other members are listed here along with the agenda. This committee includes John Christy, so there will be some ability to present alternative views of the surface temperature trend data.  However, a number of the attendees already have shown a bias in their viewpoints and even explicit successful attempts to suppress alternative viewpoints (e.g. Tom Peterson who is now President Commission of Climatology and NOAA NCDC Chief Scientist and Peter Thorne who is Chair of this meeting and now also works at NOAA NCDC).

I propose a litmus test to ascertain if this meeting is just another exercise by these scientists to endorse the analyses that they have already reported on in the 2007 IPCC WG  and the CCSP reports, or is finally an honest attempt to examine the existing biases and uncertainties.  One test will be how they respond to the peer-reviewed issues we raised in our papers

Klotzbach, P.J., R.A. Pielke Sr., R.A. Pielke Jr., J.R. Christy, and R.T. McNider, 2009: An alternative explanation for differential temperature trends at the surface and in the lower troposphere. J. Geophys. Res., 114, D21102, doi:10.1029/2009JD011841.

Klotzbach, P.J., R.A. Pielke Sr., R.A. Pielke Jr., J.R. Christy, and R.T. McNider, 2010: Correction to: “An alternative explanation for differential temperature trends at the surface and in the lower troposphere. J. Geophys. Res., 114, D21102, doi:10.1029/2009JD011841″, J. Geophys. Res., 115, D1, doi:10.1029/2009JD013655

Pielke Sr., R.A., C. Davey, D. Niyogi, S. Fall, J. Steinweg-Woods, K. Hubbard, X. Lin, M. Cai, Y.-K. Lim, H. Li, J. Nielsen-Gammon, K. Gallo, R. Hale, R. Mahmood, S. Foster, R.T. McNider, and P. Blanken, 2007: Unresolved issues with the assessment of multi-decadal global land surface temperature trends. J. Geophys. Res., 112, D24S08, doi:10.1029/2006JD008229.

Pielke Sr., R.A., C. Davey, D. Niyogi, S. Fall, J. Steinweg-Woods, K. Hubbard, X. Lin, M. Cai, Y.-K. Lim, H. Li, J. Nielsen-Gammon, K. Gallo, R. Hale, R. Mahmood, S. Foster, R.T. McNider, and P. Blanken, 2009: Reply to comment by David E. Parker, Phil Jones, Thomas C. Peterson, and John Kennedy on “Unresolved issues with the assessment of multi-decadal global land surface temperature trends. J. Geophys. Res., 114, D05105, doi:10.1029/2008JD010938.

If they ignore these papers and others papers by our colleagues (e.g. McIntyre et al 2010), or dismiss them without a thorough rationale why, this will confirm that this meeting is just a self-justification exercise. If they seriously consider this other work, however, it would be an important step forward to achieving a more robust land temperature assessment.  I am not optimistic, unfortunately.

Finally, we will be reporting on several new papers in the coming weeks and months that will provide further documentation of the serious issues with the use of the land surface temperature  data to assess multi-decadal trends. This will include the quantitative analysis of the well- and poorly- sited USHCN sites that Anthony Watts and volunteers have been instrumental in surveying. 

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Comments By Hans Schellnhuber On Climate Science

There has been recent comments regarding the views of Hans Schellnhuber on climate science, who is a major advisor on climate issues with the German government; i.e. see

Schellnhuber in Der Spiegel

H.J. Schellnhuber Interview in English translation

In 2003, I co-authored a paper with Hans and feel it is useful to post on this paper today, including several extracts from the text that he agreed with. The article is

Pielke, R.A. Sr., H.J. Schellnhuber, and D. Sahagian, 2003: Non-linearities in the Earth system. Global Change Newsletter, No. 55, 11-15.

Excerpts read

“On all time scales, the various non-linear interactions are characterised by drivers and responses that are not proportional. Changes in state are often episodic and abrupt, and multiple equilibria commonly exist. One consequence of such a non-linear system is that forecasts based on current modelling tools should be viewed sceptically. For example, since none of the general circulation models (GCMs) used to project climate change over the next hundred years include all of the important forcings and feedbacks, they should be considered as sensitivity studies rather than forecasts [10]. In Earth System science, climate is not the long term average of weather statistics, but involves the non-linear interactions between the atmosphere, oceans, continental ice, and land surface processes, including vegetation, on all time scales.”

“Research to-date has revealed the need to establish the limits to predictability within the Earth System. It has been shown that climate prediction needs to be treated as an initial value problem with chaotic behaviour. This perspective acknowledges that beyond some time period, our ability to provide reliable quantitative and detailed projections of climate must deteriorate to a level that no longer provides useful information to policymakers.”

These views present a much less certain view in the understanding of the climate system, and the ability to skillfully predict climate in the coming decades than has been presented by Hans in his Die Spiegel article.

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Comment On Tree Ring Proxy Data and Thermometer Type Surface Temperature Anomalies And Trends

There was an interesting conclusion in a New York Times article on the relationship between tree ring proxy temperature trend analyses and thermometer type measures of temperature anomalies and trends.  The article is

British Panel Clears Scientists  by Justin Gillis published on July 7, 2010

The relevant text is on page 2 it is written

“But they were dogged by a problem: Since around 1960, for mysterious reasons, trees have stopped responding to temperature increases in the same way they apparently did in previous centuries. If plotted on a chart, tree rings from 1960 forward appear to show declining temperatures, something that scientists know from thermometer readings is not accurate.”

There are, however, problems with this conclusion. Since the thermometers are not coincident in location with the tree ring data (in the same local area), it would not be surprising that they are different. Indeed, this is yet another example that implies unresolved biases and uncertainties in the surface temperature thermometer type data as we discussed in several of our papers (see and see), as the thermometers are measuring elsewhere then where the proxy tree data is obtained.  This obvious issue has been ignored in the assessment of this so-called divergence between the two methods to evaluate temperature anomalies and trends.

It is possible, of course, that the trees are responding differently due to the biogeochemical effect of added carbon dioxide and/or nitrogen deposition. Nonetheless, to accept the thermometer record as the more robust measurement of spatial representative temperatures is premature.

I have discussed this issue further in the posts

Comments On The Tree Ring Proxy and Thermometer Surface Temperature Trend Data

December 2007 Session ‘The “Divergence Problem’ In Northern Forests

A New Paper On The Differences Between Recent Proxy Temperature And In-Situ Near-Surface Air Temperatures

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Recommended Book “The Climate Fix” By Roger A. Pielke Jr.

Most readers of my weblog also probably read that of my son’s [http://rogerpielkejr.blogspot.com/].  For those who do not, however, I am reposting his announcement of yesterday;

Free Preview of The Climate Fix

I have read the book and it should be read by everyone who is interested in climate science and climate policy. I 100% support his recommended path forward.

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Paper On Martian Dust Storms That Is Relevant For Earth’s Climate – Rafkin Et Al 2009

I was alerted to a paper on Martian weather that is relevant for the weather and climate on Earth. It involves the role of dust, as a diabatic heat source, in affecting atmospheric circulations. On Earth, dust comes from a variety of sources, including deserts and degraded semi-arid landscapes.  Biomass burning and industrial aerosol emissions are other sources.

As emphasized om my weblog and in our papers (e.g. see), the heterogeneous heating by aerosol clouds is a major under appreciated human and natural climate forcing, as was reported in NRC (2005).

The Mars paper is

Rafkin, S. C. R. (2009), A positive radiative-dynamic feedback mechanism for the maintenance and growth of Martian dust storms, J. Geophys. Res., 114, E01009, doi:10.1029/2008JE003217.

The abstract reads

“Atmospheric dust disturbances ranging in size from dust devils to planet-encircling dust storms are ubiquitous on Mars. After dust devils, the most common disturbances are local- or regional-scale disturbances. The origin of some of these mesoscale systems has been previously investigated and found to be linked to lifting along frontal systems or cap edge circulations. Very little attention has been given to whether the lifted dust in these systems result in radiative forcing that might modulate the local system dynamics with an amplitude large enough to affect local dust-lifting processes. Idealized numerical modeling results presented herein show that a positive feedback process between local dynamics and radiative forcing of lifted dust can occur under some conditions. The feedback process is distinctly different than an enhancement of the general circulation by increasing atmospheric dust loading because the dynamical effects of this feedback process occur locally, within the disturbance itself. Optimal conditions for growth of initial atmospheric dust perturbations include (1) subtropical latitudes associated with relatively large solar insolation and moderate coriolis force; (2) modest dust-lifting thresholds and dust-lifting efficiencies; (3) relatively large initial dust perturbations; (4) steep background lapse rates; and (5) a barotropic environment. The positive feedback process is explained by a combination of geostrophic adjustment theory and a Carnot engine-like mechanism related to the Wind-Induced Sensible Heat Exchange hypothesis for tropical cyclones on Earth.”

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Soot and Climate Change – A New Article By Jacobson 2010

The article is

Jacobson, M. Z. (2010), Short‐term effects of controlling fossil‐fuel soot, biofuel soot and gases, and methane on climate, Arctic ice, and air pollution health, J. Geophys. Res., 115, D14209, doi:10.1029/2009JD013795.

The abstract reads

“This study examines the short‐term (∼15 year) effects of controlling fossil‐fuel soot (FS) (black carbon (BC), primary organic matter (POM), and S(IV) (H2SO4(aq), HSO4−, and SO42−)), solid‐biofuel soot and gases (BSG) (BC, POM, S(IV), K+, Na+, Ca2+, Mg2+, NH4+, NO3−, Cl− and several dozen gases, including CO2 and CH4), and methane on global and Arctic temperatures, cloudiness, precipitation, and atmospheric composition. Climate response simulations were run with GATOR‐GCMOM, accounting for both microphysical (indirect) and radiative effects of aerosols on clouds and precipitation. The model treated discrete size‐resolved aging and internal mixing of aerosol soot, discrete size‐resolved evolution of clouds/precipitation from externally and internally mixed aerosol particles, and soot absorption in aerosols, clouds/precipitation, and snow/sea ice. Eliminating FS, FS+BSG (FSBSG), and CH4 in isolation were found to reduce global surface air temperatures by a statistically significant 0.3–0.5 K, 0.4–0.7 K, and 0.2–0.4 K, respectively, averaged over 15 years. As net global warming (0.7–0.8 K) is due mostly to gross pollutant warming from fossil‐fuel greenhouse gases (2–2.4 K), and FSBSG (0.4–0.7 K) offset by cooling due to non‐FSBSG aerosol particles (−1.7 to −2.3 K), removing FS and FSBSG may reduce 13–16% and 17–23%, respectively, of gross warming to date. Reducing FS, FSBSG, and CH4 in isolation may reduce warming above the Arctic Circle by up to ∼1.2 K, ∼1.7 K, and ∼0.9 K, respectively. Both FS and BSG contribute to warming, but FS is a stronger contributor per unit mass emission. However, BSG may cause 8 times more mortality than FS. The global e‐folding lifetime of emitted BC (from all fossil sources) against internal mixing by coagulation was ∼3 h, similar to data, and that of all BC against dry plus wet removal was ∼4.7 days. About 90% of emitted FS BC mass was lost to internal mixing by coagulation, ∼7% to wet removal, ∼3% to dry removal, and a residual remaining airborne. Of all emitted plus internally mixed BC, ∼92% was wet removed and ∼8% dry removed, with a residual remaining airborne. The 20 and 100 year surface temperature response per unit continuous emissions (STRE) (similar to global warming potentials (GWPs)) of BC in FS were 4500–7200 and 2900–4600, respectively; those of BC in BSG were 2100–4000 and 1060–2020, respectively; and those of CH4 were 52–92 and 29–63, respectively. Thus, FSBSG may be the second leading cause of warming after CO2. Controlling FS and BSG may be a faster method of reducing Arctic ice loss and global warming than other options, including controlling CH4 or CO2, although all controls are needed.”

As Bill pointed out in an e-mail, this paper is further confirmation that hypothesis 2a in

Pielke Sr., R., K. Beven, G. Brasseur, J. Calvert, M. Chahine, R. Dickerson, D. Entekhabi, E. Foufoula-Georgiou, H. Gupta, V. Gupta, W. Krajewski, E. Philip Krider, W. K.M. Lau, J. McDonnell,  W. Rossow,  J. Schaake, J. Smith, S. Sorooshian,  and E. Wood, 2009: Climate change: The need to consider human forcings besides greenhouse gases. Eos, Vol. 90, No. 45, 10 November 2009, 413. Copyright (2009) American Geophysical Union.

is the correct one. Hypothesis 2a reads

“Although the natural causes of climate variations and changes are undoubtedly important, the human influences are significant and involve a diverse range of first- order climate forcings, including, but not limited to, the human input of carbon dioxide (CO2). Most, if not all, of these human influences on regional and global climate will continue to be of concernduring the coming decades.”

and that

“In addition to greenhouse gas emissions, other first-order human climate forcings are important to understanding the future behavior of Earth’s climate. These forcings are spatially heterogeneous and include the effect of aerosols on clouds and associated precipitation [e.g., Rosenfeld et al., 2008], the influence of aerosol deposition (e.g., black carbon (soot) [Flanner et al. 2007] and reactive nitrogen [Galloway et al., 2004]), and the role of changes in land use/land cover [e.g., Takata et al., 2009]. Among their effects is their role in altering atmospheric and ocean circulation features away from what they would be in the natural climate system [NRC, 2005].”

There is an AGU press release on this article, and excerpts from the release are reproduced below:

The study shows that soot is second only to carbon dioxide in contributing to global warming. But, climate models to date have mischaracterized the effects of soot in the atmosphere, said its author Mark Z. Jacobson of Stanford University in Stanford, California. Because of that, soot’s contribution to global warming has been ignored completely in national and international global warming policy legislation, he said.

“Controlling soot may be the only method of significantly slowing Arctic warming within the next two decades,” said Jacobson, director of Stanford’s Atmosphere/Energy Program. “We have to start taking its effects into account in planning our mitigation efforts and the sooner we start making changes, the better.”

“Soot — black and brown particles that absorb solar radiation — comes from two types of sources: fossil fuels such as diesel, coal, gasoline, jet fuel; and solid biofuels such as wood, manure, dung, and other solid biomass used for home heating and cooking around the world.

Jacobson found that the combination of the two types of soot is the second-leading cause of global warming after carbon dioxide. That ranks the effects of soot ahead of methane, an important greenhouse gas. He also found that soot emissions kill over 1.5 million people prematurely worldwide each year, and afflicts millions more with respiratory illness, cardiovascular disease, and asthma, mostly in the developing world where biofuels are used for home heating and cooking.

Jacobson found that eliminating soot produced by the burning of fossil fuel and solid biofuel could reduce warming above parts of the Arctic Circle in the next fifteen years by up to 1.7 degrees Celsius (3 degrees Fahrenheit). For perspective, net warming in the Arctic has been at least 2.5 degrees Celsius (4.5 degrees Fahrenheit) over the last century and is expected to warm significantly more in the future if nothing is done.”

There is another summary of this article that Bill alerted us to with a model simulation graph:  http://www.wired.com/wiredscience/2010/07/soot-control/

This is yet another peer reviewed study that highlights the incompleteness of the 2007 IPCC assessment reports.

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Paper “Water Vapor And The Dynamics Of Climate Changes” By Schneider Et Al 2010

There is a recent paper on the role of water vapor in the climate system which presents an much needed broadening beyond the role of carbon dioxide as the dominant climate forcing, as is emphasized in the 2007 IPCC WG report [and thanks to Faisal Hossain for alerting us to it!] .The paper is

Schneider, T., P. A. O’Gorman, and X. J. Levine (2010), WATER VAPOR AND THE DYNAMICS OF CLIMATE CHANGES, Rev. Geophys., 48, RG3001, doi:10.1029/2009RG000302.

The abstract reads

“Water vapor is not only Earth’s dominant greenhouse gas. Through the release of latent heat when it condenses, it also plays an active role in dynamic processes that shape the global circulation of the atmosphere and thus climate. Here we present an overview of how latent heat release affects atmosphere dynamics in a broad range of climates, ranging from extremely cold to extremely warm. Contrary to widely held beliefs, atmospheric circulation statistics can change nonmonotonically with global-mean surface temperature, in part because of dynamic effects of water vapor. For example, the strengths of the tropical Hadley circulation and of zonally asymmetric tropical circulations, as well as the kinetic energy of extratropical baroclinic eddies, can be lower than they presently are both in much warmer climates and in much colder climates. We discuss how latent heat release is implicated in such circulation changes, particularly through its effect on the atmospheric static stability, and we illustrate the circulation changes through simulations with an idealized general circulation model. This allows us to explore a continuum of climates, to constrain macroscopic laws governing this climatic continuum, and to place past and possible future climate changes in a broader context.”

The finding that

“Contrary to widely held beliefs, atmospheric circulation statistics can change nonmonotonically with global-mean surface temperature…”

reinforces what we have reported on; e.g. see

What is the Importance to Climate of Heterogeneous Spatial Trends in Tropospheric Temperatures?

that it is the atmospheric and ocean regional circulation patterns  [rather than a global average of any climate metric] that matters in terms of such societally and environmentally important events such as droughts, floods etc.  While the Schneider et al 2009 paper still emphasizes a global perspective (since they use an idealized global circulation model), their conclusion regarding atmospheric circulations is a message that the new IPCC assessment needs to heed.

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Illustration Of The Spatial Distribution Of The Russian Heat Wave

Anthony Watts at Watts Up With That has provided us with the analysis of surface temperature anomalies from NASA’s Earth Observatory of the July 21-27 2010 relative to the same dates in the years 2000-2008.  The regional distribution of the warm and cold events is clear from this figure.

Heatwave in Russia

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Heat Wave In Russia – Is It From Global Warming?

There has been considerable discussion of the heat wave in Russia and of the floods in Pakistan and China as to whether these events are from global warming.  Examples of this in the media include

Will Russia’s Heat Wave End Its Global-Warming Doubts?  By Simon Shuster / Moscow

Climate change whips up floods, fire and ice by Brian Sullivan and Madelene Pearson

The second article starts with the text

CLIMATE change has been blamed for floods that have killed thousands and left millions homeless from Pakistan to North Korea, fires and a heatwave in Russia that have left 5000 dead and disrupted global food markets, and a severe tropical storm threatening Bermuda.

and includes the statements

The weather drew comment from officials and activists at international climate change talks in Bonn.

One US delegate said Russia’s heatwave and the recent floods that have devastated Pakistan are ”consistent with the kind of changes we would expect to see from climate change and they will only get worse unless we act quickly”.

A new article in the Economist

Green View: A taste of things to come

has a more complete discussion for these weather events. Excerpts from the article includes the text

“The immediate cause of the problems is the behaviour of the jet stream, a band of high-level wind that travels east around the world and influences much of the weather below it. Part of the jet stream’s meandering is tied to regular shifts of air towards and away from the pole, called Rossby waves. The Rossby waves set up wiggles in the jet stream, wiggles which, left to themselves, would move westward. Since the jet stream is flowing eastward, though, the net effect of the Rossby waves varies. When the waves are short, they go with the jet’s flow and the resultant wiggling heads downstream to the east. When they are long they go against the flow, and the jet’s wiggling is transmitted upstream to the west. In between, there is a regime in which the waves move neither west nor east, and the weather stays put.”

Part of the straightforwardness of that analysis is that it treats all the previous years equally. When instead Dr van Oldenborgh takes into account that there has been a general warming trend over those past 60 years the heatwave starts to look less improbable—more like the sort of thing you might expect every century. As the warming trend continues in the future, the chances of such events being repeated more frequently will get higher. A single heatwave cannot be said to have been caused by global climate change; but what is known about climate change says such heatwaves are now more probable than they were.

The intensity of this heatwave has been remarkable. It is hotter than at any time in the instrumental record. According to an analysis by Geert Jan van Oldenborgh of the Royal Netherlands Meteorological Institute a straightforward comparison of the temperatures seen this summer with those of the past 60 years suggests that a large patch of Russia is experiencing temperatures which might be expected only once every 400 years or so. Some places within that patch are hotter than might be expected over several millennia.

In a world where greenhouse warming gets stronger, the tropics expand—an effect the beginning of which has already been observed. The paths of the jet streams to the north and south of the tropics will change in response to this. What that means for the interactions between jet streams and Rossby waves that lead to blocking, though, is unclear. Tony Lupo, an atmospheric scientist from the University of Missouri, has been looking at the question with some Russian colleagues. He says their climate modelling provides some reason to believe blocking effects might become more common in a warmer world, but also less forceful.

The attribution of the heat wave to atmospheric blocking this summer is a scientifically sound conclusion.   The heat can occur from

  • the advection of hot air from lower latitudes on the west side of a warm core anticyclone
  • from compressional warming due to sinking air in the troposphere associated with the warm core anticyclone
  • from a larger portion of solar insolation going into sensible versus latent surface heating as result of dry soils and stressed vegetation that occurs due to the absence of rainfall associated with the core of these anticyclones
  • from added heating of the atmosphere from the absorption of solar insolation by aerosols from forest fires that occur in this dry environment.

[for a discussion of warm core anticyclones, see

Pielke Sr., R.A. 2002: Synoptic Weather Lab Notes. Colorado State University, Department of Atmospheric Science Class Report #1, Final Version, August 20, 2002.]

 However, the statements that the tropics have expanded in recent years and the probabilities that such heat waves are becoming more common has not yet convincingly been made.

Indeed we looked at this issue for the heat wave in Europe in 2003 in the paper

Chase, T.N., K. Wolter, R.A. Pielke Sr., and Ichtiaque Rasool, 2006: Was the 2003 European summer heat wave unusual in a global context? Geophys. Res. Lett., 33, L23709, doi:10.1029/2006GL027470

where we found that the 2003 heat anomaly was particularly extreme near the surface (perhaps due to dry soil) but less anomalous in the rest of the troposphere. Our conclusions were confirmed in

Connolley W.M. 2008: Comment on “Was the 2003 European summer heat wave unusual in a global context?” by Thomas N. Chase et al. Geophys. Res. Lett., 35, L02703, doi:10.1029/2007GL031171.

We updated our analysis in

Chase, T.N., K. Wolter, R.A. Pielke Sr., and Ichtiaque Rasool, 2008: Reply to comment by W.M. Connolley on ‘‘Was the 2003 European summer heat wave unusual in a global context?’’Geophys. Res. Lett., 35, L02704, doi:10.1029/2007GL031574.

 In the Chase et al 2008 paper we reported that

Figure 1 updates Chase et al. [2006] through 2006 for 2.0 and 3.0 SD levels and adds to our original conclusion that 2003 was not very unusual in terms of the spatial coverage of extreme depth-averaged temperatures.

and

However, the addition of three additional summers (2004– 2006) to the time series, all of which appear to be relatively warm, now indicates the possible emergence of an upward trend as suggested in previous work [Stott et al., 2004]. For example 2.0 SD warm anomalies now appear to have an upward trend (p = 0.05) though this trend should be viewed with caution because of the small sample size and the dominant effect of data points at the end of the series. The rise in 3.0 SD anomalies comparable to the 2003 heat wave is, however, still insignificant (p = 0.16) and so the increased probability of such extremes with time suggested by Stott et al. [2004] is not yet apparent.

Tom Chase will be updating this analysis through August 2010 in early September when the data becomes available. Then, instead of qualitative claims about an expanding tropics and a greater frequency of heat waves, actual climate data will be available to quantify whether or not the claims made concerning the tropospheric temperature anomalies are robust or not.

We have certainly seen a warm troposphere this year. The July lower tropospheric temperature anomalies were presented in my August 5 2010 post and the global spatial plot is reproduced below

The heat wave in western Russia is clear in the data along with a substantial warm anomaly in eastern Russia and part of China, as are smaller warm anomalies in other locations worldwide. Only Antarctica has a large negative anomaly [although interestingly, Pakistan has a modest below average lower tropospheric temperature anomaly]

This warmth presents an opportunity in the coming months to assess whether this is really related to a long term global warming related effect, or is due to some other aspects of the climate system (perhaps as modified by spatially heterogeneous forcing due to human activity including land use change and aerosols).

If it is a long term global warming signature, than the global average tropospheric warm anomaly will persist when the blocking pattern is removed.  If, however, the lower tropospheric temperatures cool to or below their long term average and this heat cannot be found in the oceans, long term global warming cannot be the culprit.  I will report on this early in 2011. 

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“Is Jim Hansen’s Global Temperature Skillful?” Guest Post by John R. Christy

Guest Post By John R. Christy of the University of Alabama at Huntsville

The three warm-color time series are taken from Hansen’s published testimony in June 1988 in which global surface air temperatures were projected under three scenarios by his global climate model. The red curve follows a scenario (A) of continued emissions growth based on the previous 20 years before 1988 (which turned out to be an underestimate of actual emissions growth.) The orange represents a scenario (B) of fixed emissions at the rate achieved in the 1980s. The yellow curve portrays a scenario (C) in which “a drastic reduction” in GHG emissions is assumed for 1990-2000. The observations are global tropospheric temperatures adjusted to mimic the magnitude of surface temperature variability and trends according to published climate model simulations (i.e. a reduction in satellite anomalies by 0.83.)

After tying all time series to a 1979-83 reference mean, one can see the significant divergence in the results. (Notes: 1. observed 2010 is Jan-Jul only; 2.) tropospheric temperatures are used as the comparison metric due to many uncertainties and biases in the surface temperature record, i.e. Klotzbach et al. 2009, 2010 ; 3.) both models and observations included the 1982 eruption of El Chichon while B and C scenarios included a volcano in the mid 1990s – not too different from Mt. Pinatubo.)

The result suggests the old NASA GCM was considerably more sensitive to GHGs than is the real atmosphere since (a) the model was forced with lower GHG concentrations than actually occurred and (b) still gave a result that was significantly warmer than observations.

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