Monthly Archives: October 2008

Interview On Mother Jones

Mother Jones has just published an interview with me by Kiera Butler that was conducted several months ago: Q&A: Roger A. Pielke Sr.  It is discussed very effectively by my son on Prometheus yesterday (see).

As written in the Prometheus weblog, it is a pretty good interview (although some editing would have made several of the issues clearer and the header to the interview oversimplifies my perspective). Nonetheless, presenting my different perspective, which is broader and more inclusive than reported  in the IPCC and CCSP reports, is an example of open-minded and effective journalism.

For other summaries of my perspective on climate science, please read

Roger A. Pielke Sr.’s Perspective On The Role Of Humans In Climate Change

Roger A. Pielke Sr.’s Perspective On Adaptation and Mitigation


House Testimony of Roger A. Pielke Sr. “A Broader View of the Role of Humans in the Climate System is Required In the Assessment of Costs and Benefits of Effective Climate Policy”.


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Filed under Climate Science Reporting, Q & A on Climate Science, RA Pielke Sr. Position Statements

Comments on a New Report on Climate Change in Colorado: A Synthesis to Support Water Resources Management and Adaptation for the Colorado Water Conservation Board by Ray et al. 2008

Recently a report titled

“Climate Change in Colorado:  A Synthesis to Support Water Resources Management and Adaptation for the Colorado Water Conservation Board” by Andrea J. Ray, Joseph J. Barsugli, Kristen B. Averyt, Martin Hoerling, and Klaus Wolter

was released. The report has valuable information on the climate of Colorado and is written by well-respected climate scientists.

However, the Report is has serious flaws in providing guidance to policymakers on dealing with water resource issues in Colorado in the coming decades. Three of the major deficiencies in the report can be summarized as follows.

1.  Use Of The IPCC Models To Predict Colorado Climate Out To 2050.

The statement in the Report that

“Climate models project Colorado will warm by 2°F by 2025, and 4°F by 2050. The projections show summers warming more (+5°F) than winters (+3°F), and suggest that typical summer temperatures in 2050 will be as warm as or warmer than the hottest 10% of summers that occurred between 1950 and 1999. By 2050, temperatures on the Eastern Plains of Colorado will shift westward and upslope, bringing into the Front Range temperature regimes that today occur near the Kansas border.”

is just a hypothesis based on global models that do not have all of the first-order human climate forcings, as well as all of the important climate feedbacks. There is no skill at regional forecasts decades into the future.

There have been a variety of statements and papers that emphasize that the IPCC multi-decadal climate models have no regional skill (even when downscaled). For example, one of the IPCC Lead Authors, Kevin Trenberth, in a candid weblog [; see also],  stated

“None of the models used by IPCC are initialized to the observed state and none of the climate states in the models correspond even remotely to the current observed climate.”

“I [Kevin Trenberth] postulate that regional climate change is impossible to deal with properly unless the models are initialized.”

“….the science is not done because we do not have reliable or regional predictions of climate.”

A recent example of a peer-reviewed paper that documents the inability of the IPCC models to skillfully predict regional climate is

Koutsoyiannis, D., A. Efstratiadis, N. Mamassis, and A. Christofides, 2008: On the credibility of climate predictions, Hydrological Sciences Journal, 53 (4), 671-684

Where they write

“Geographically distributed predictions of future climate, obtained through climate models, are widely used in hydrology and many other disciplines, typically without assessing their reliability. Here we compare the output of various models to temperature and precipitation observations from eight stations with long (over 100 years) records from around the globe. The results show that models perform poorly, even at a climatic (30-year) scale. Thus local model projections cannot be credible, whereas a common argument that models can perform better at larger spatial scales is unsupported.”
“At the annual and the climatic (30-year) scales, GCM interpolated series are irrelevant to reality……future climate projections at the examined locations not credible. Whether or not this conclusion extends to other locations requires expansion of the study, which we have planned. However, the poor GCM performance in all eight locations examined in this study allows little hope, if any. An argument that the poor performance applies merely to the point basis of our comparison, whereas aggregation at large spatial scales would show that GCM outputs are credible, is an unproved conjecture and, in our opinion, a false one.”
The claim to be able to skillfully project Colorado climate out to 2050 is scientifically invalid and will mislead policymakers. There is no skill in multi-decadal regional climate predictions for Colorado.
2.   The reliance of the Colorado report on the 2007 IPCC and CCSP Reports, which attribute recent climate change to primarily the “thickening blanket of greenhouse gases (including carbon dioxide)” , is scientifically flawed.
The failure of the IPCC and CCSP reports to adequately assess the state of climate science is summarized in Comments On The Draft CCSP Report “Global Climate Change Impacts in the United States” []

Where I wrote

“This Draft CCSP report failed to adequately report on the understanding of the role of humans within the climate system by the climate science community. As just one example, the statement is made in the text that

“Human-induced climate change and its impacts are apparent now throughout the United States. Global warming is unequivocal and is due primarily to human-induced emissions of heat-trapping gases and other pollutants.”

This claim is inconsistent with the conclusions in the 2005 NRC report that there are other first-order human climate forcings;

National Research Council, 2005: Radiative forcing of climate change: Expanding the concept and addressing uncertainties. Committee on Radiative Forcing Effects on Climate Change, Climate Research Committee, Board on Atmospheric Sciences and Climate, Division on Earth and Life Studies, The National Academies Press, Washington, D.C., 208 pp

where it is concluded that

“Regional variations in radiative forcing may have important regional and global climatic implications that are not resolved by the concept of global mean radiative forcing…Regional diabatic heating can also cause atmospheric teleconnections that influence regional climate thousands of kilometers away from the point of forcing. Improving societally relevant projections of regional climate impacts will require a better understanding of the magnitudes of regional forcings and the associated climate responses.” [page 5 of the 2005 NRC report]


Several types of forcings, most notably aerosols, land-use and land-cover change, and modifications to biogeochemistry, impact the climate system in nonradiative ways, in particular by modifying the hydrological cycle and vegetation dynamics. Aerosols exert a forcing on the hydrological cycle by modifying cloud condensation nuclei, ice nuclei, precipitation efficiency, and the ratio between solar direct and diffuse radiation received. Other nonradiative forcings modify the biological components of the climate system by changing the fluxes of trace gases and heat between vegetation, soils, and the atmosphere and by modifying the amount and types of vegetation…..Nonradiative forcings have eventual radiative impacts, so one option would be to quantify these radiative impacts. However, this approach may not convey appropriately the impacts of nonradiative forcings on societally relevant climate variables such as precipitation or ecosystem function. Any new metrics must also be able to characterize the regional structure in nonradiative forcing and climate response.” [page 6 of the 2005 NRC report].

Thus, the scientific evidence presented in the 2005 NRC report supports the perspective that

The human influence on the climate system is significant and involves a diverse range of first-order climate forcings, including, but not limited to the human input of CO2

The failure of the IPCC and CCSP process to accurately communicate the current understanding of climate science is also summarized in

Pielke Sr., Roger A., 2008: A Broader View of the Role of Humans in the Climate System is Required In the Assessment of Costs and Benefits of Effective Climate Policy. Written Testimony for the Subcommittee on Energy and Air Quality of the Committee on Energy and Commerce Hearing “Climate Change: Costs of Inaction” – Honorable Rick Boucher, Chairman. June 26, 2008, Washington, DC., 52 pp

 where the oral statement reads, in part,

“The human addition of CO2 into the atmosphere is a first-order climate forcing. We need an effective policy to limit the atmospheric concentration of this gas. However, humans are significantly altering the climate system in a diverse range of ways in addition to CO2. The information that I am presenting will assist in properly placing CO2 policies into the broader context of climate policy.
Climate is much more than just long-term weather statistics but includes all physical, chemical, and biological components of the atmosphere, oceans, land surface, and glacier-covered areas. In 2005, the National Research Council published a report “Radiative forcing of climate change: Expanding the concept and addressing uncertainties” that documented that a human disturbance of any component of the climate system, necessarily alters other aspects of the climate……
Thus climate policy that is designed to mitigate the human impact on regional climate by focusing only on the emissions of CO2is seriously incomplete unless these other first-order human climate forcings are included, or complementary policies for these other human climate forcings are developed. Moreover, it is important to recognize that climate policy and energy policy, while having overlaps, are distinctly different topics with different mitigation and adaptation options.
A way forward with respect to a more effective climate policy is to focus on the assessment of adaptation and mitigation strategies that reduce vulnerability of important societal and environmental resources to both natural and human caused climate variability and change. For example, restricting development in flood plains or in hurricane storm surge coastal locations is an effective adaptation strategy regardless of how climate changes.

In conclusion, humans are significantly altering the global climate, but in a variety of diverse ways beyond the radiative effect of carbon dioxide. The CCSP assessments have been too conservative in recognizing the importance of these human climate forcings as they alter regional and global climate. These assessments have also not communicated the inability of the models to accurately forecast future regional climate on multi-decadal time scales since these other first-order human climate forcings are excluded. The forecasts, therefore, do not provide skill in quantifying the impact of different mitigation strategies on the actual climate response that would occur as a result of policy intervention with respect to only CO2.”

Thus the basic foundation of the Colorado report on the attribution of the dominate reason for climate change to be “the thickening blanket of greenhouse gases (including carbon dioxide)” is scientifically invalid.

3.   In documenting recent changes in Colorado climate, the report was incomplete in presenting peer-reviewed research which presents a more complex pattern of variability and change.

These papers include

Pielke Sr., R.A., T. Stohlgren, W. Parton, J. Moeny, N. Doesken, L. Schell, and K. Redmond, 2000: Spatial representativeness of temperature measurements from a single site. Bull. Amer. Meteor. Soc., 81, 826-830.

Pielke Sr., R.A., T. Stohlgren, L. Schell, W. Parton, N. Doesken, K. Redmond, J. Moeny, T. McKee, and T.G.F. Kittel, 2002: Problems in evaluating regional and local trends in temperature: An example from eastern Colorado, USA. Int. J. Climatol., 22, 421-434

 [this paper is included in the report, but its major findings are not].

Davey, C.A., and R.A. Pielke Sr., 2005: Microclimate exposures of surface-based weather stations – implications for the assessment of long-term temperature trends. Bull. Amer. Meteor. Soc., Vol. 86, No. 4, 497-504.

Pielke Sr., R.A., C. Davey, and J. Morgan, 2004: Assessing “global warming” with surface heat content. Eos, 85, No. 21, 210-211.

Hanamean, J.R. Jr., R.A. Pielke Sr., C.L. Castro, D.S. Ojima, B.C. Reed, and Z. Gao, 2003: Vegetation impacts on maximum and minimum temperatures in northeast Colorado. Meteorological Applications, 10, 203-215.

Pielke Sr., R.A., and T. Matsui, 2005: Should light wind and windy nights have the same temperature trends at individual levels even if the boundary layer averaged heat content change is the same? Geophys. Res. Letts., 32, No. 21, L21813, 10.1029/2005GL024407.

Lin, X., R.A. Pielke Sr., K.G. Hubbard, K.C. Crawford, M. A. Shafer, and T. Matsui, 2007: An examination of 1997-2007 surface layer temperature trends at two heights in Oklahoma. Geophys. Res. Letts., 34, L24705, doi:10.1029/2007GL031652.

Fall, S., D. Niyogi, R.A. Pielke Sr., A. Gluhovsky, and E. Kalnay, 2008: Impacts of land surface properties on temperature trends using North American regional reanalysis over the USA. Int. J. Climatol., in revision.

Pielke Sr., R.A., N. Doesken, O. Bliss, T. Green, C. Chaffin, J.D. Salas, C. Woodhouse, J.L. Lukas, and K. Wolter, 2005: Drought 2002 in Colorado – An unprecedented drought or a routine drought? Pure Appl. Geophys., Special Issue in honor of Prof. Singh, 162, 1455-1479, doi:10.1007/200024-005-2679-6.

Pielke, R.A. Sr., K. Wolter, O. Bliss, N. Doesken, and B. McNoldy, 2006: The July 2005 Denver heat wave: How unusual was it? Nat. Wea. Dig., 31, 24-35. 

In the Pielke et al. (2002) paper, for example, we evaluated long-term trends in average maximum and minimum temperatures, threshold temperatures, and growing season in eastern Colorado and found a wide variety of trends. Davey and Pielke (2005) photographically documented the poor siting exposures of the sites used to examine long-term temperature trends [and this photographic documentation should be a required part of the current report for each of the stations listed in this report].

Pielke et al. (2004) showed that unless the trends in dewpoint temperature are measured at the same times as the dry bulb temperature, the attribution of temperature changes to large-scale atmospheric, rather than to surface landscape changes, could be erroneous. Pielke and Matsui (2005) and Lin et al. (2007) show that the use of the minimum temperature, measured at just one level, results in a significant warm bias if the overall boundary layer were warming (e.g., due to cloud cover changes, land-use change, as well as local increased atmospheric concentrations of CO2 and/or water vapor). In the global long-term temperature record, about 30% of the reported warming, that has been reported by the IPCC can be explained by this one warm bias.

The report ignored research studies in Colorado which present a more complex variation of regional climate during the last several decades, as well as document a diversity of reasons for these variations.


With respect to the report on trends and variability of temperature and precipitation in Colorado in the past, the report should have included the information that they did provide, but it needs also to be inclusive of all the available studies that present a more complex pattern of trends.

The summary of the data should not use the IPCC models to attribute the trends to primarily human-induced emissions of heat-trapping gases and other pollutants, nor to provide regional forecasts to policymakers. The authors of the report are just repeating the claims in the IPCC and CCSP reports which have been shown to be seriously incomplete.

I had recommended in my reviews of the report that they delete the section on the projection of the climate for Colorado for the coming decades, and replace with the vulnerability framework reported on in Chapter E in

Kabat, P., Claussen, M., Dirmeyer, P.A., J.H.C. Gash, L. Bravo de Guenni, M. Meybeck, R.A. Pielke Sr., C.J. Vorosmarty, R.W.A. Hutjes, and S. Lutkemeier, Editors, 2004: Vegetation, water, humans and the climate: A new perspective on an interactive system. Springer, Berlin, Global Change – The IGBP Series, 566 pp.

and in

Pielke Sr., R.A., J.O. Adegoke, T.N. Chase, C.H. Marshall, T. Matsui, and D. Niyogi, 2007: A new paradigm for assessing the role of agriculture in the climate system and in climate change. Agric. Forest Meteor., Special Issue, 132, 234-254. 

These papers provide a more complete assessment tool for the threats that water resources face in Colorado from the spectrum of human and natural climate and other environmental and social variations and change.

I was pleased to see, while the authors did not delete the regional projections, they did  include a short section on a bottom-up vulnerability perspective in on page 42 and Figure 6.1, in response to my comments, but they still insisted on including model projections; i.e. in Sidebar 3-2 they wrote

“Average monthly GCM changes in temperature and precipitation for 2030 and 2070 were combined with multiple recreations of the paleoclimate record to simulate the combined effects of changes in climate and paleoclimate variability.”

They also did not highlight this type of vulnerability assessment in the Executive Summary.

For example, as seen in the tree ring proxy data of precipitation in Figure 2-9 in the Report (and also see, Colorado is at major risk to climate variations and change, regardless of how humans are altering the climate system. This assessment of vulnerability to water resources, using historical, paleo-record, and selected worst-case drought scenarios (i.e., driest sequences of years) should be the focus for threats Colorado might face in the coming decades to our water supply. The use of the IPCC and CCSP reports as the basis for a very limited range of climate scenarios eliminates, for example, an assessment of the consequences if actual past drought conditions reoccured in the coming decades, but with the human demands on water that will be faced in this time period.

This issue was also weblogged on October 27 2008 in the posting

New Article On The Need To Move From Dubious Multi-Decadal Regional Climate Predictions To The Assessment of Regional Vulnerabilites.

Finally, if one or more of the authors of the report would like to write a guest weblog on this issue for Climate Science, they are invited to do so.



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Filed under Climate Change Forcings & Feedbacks, Climate Models, Climate Science Misconceptions, Vulnerability Paradigm

Poor Climate Science Article In The Economist On Glaciers

I am a fan of the Economist and have subscribed for several years. It is a very effective magazine with which to learn what is occurring throughout the world. However, its coverage of climate issues has generally been quite poor. The latest article (in the October 25 2008) issue continues this inadequate reporting. This article is titled

“Kashmir’s environment How green was my valley?

with the subheading

“Climate change will only intensify problems in Kashmir”.

The article includes the text

“…..the Kolahoi glacier……is the Kashmir valley’s only year-round source of water. But it is melting at an alarming rate………If present trends, which are blamed on climate change, continue, he concludes with a shrug, ‘In ten years there will be no Kolahoi glacier'”.

Later in the article it is written that

“According to villagers in nearby Aru, in 1985 the glacier’s snout stretched half a mile (800 metres) further down the valley.”

However, embedded within the text is the statement that

“Unfortunately, there is a dearth of reliable scientific data on the region.”

The obvious question is how can the retreat of the glacier be assummed to be continuing into the future and related to climate change (which I am assuming is meant here to be “global warming”)?

The reality of glacier advance and retreat in this region of the world is actually much more complex. This has been weblogged on previously by Climate Science; i.e. see

 Status of the Siachen Glacier In The Himalayas

where a paper

V. K. Raina and C. Sangewar, 2007 Siachen Glacier of Karakoram Mountains, Ladakh – Its Secular Retreat Journal of the Geological Society of India (Vol.70(1), July 2007, pp.11-16

reported that

“The Siachen glacier is the second largest glacier known outside the polar and sub-polar regions and the largest in the Karakoram Himalaya. The glacier with a length of 74 km is an example of the nature and size of the glaciers that must have once existed in the Himalaya towards the end of the last Ice Age. This glacier, primarily, because of its size has remained an important topic of glacier study and survey. Observation of the glacier front from 1862AD till date has revealed that there may have been a rapid advance of 700 m or so between 1862 and 1909, which was subsequently neutralised by relatively faster retreat between 1929AD and 1958AD. The glacier along its snout front has since been in rest mode, a term used in glaciology to depict glaciers with very low or practically nil retreat.”

and see

 More Evidence On the Issue Of Glacier Retreat and Advance

where a second paper

Fowler, H.J. and Archer, D.R. 2006. Conflicting signals of climatic change in the Upper Indus Basin. Journal of Climate 19: 4276-4293

concluded that

“Temperature data for seven instrumental records in the Karakoram and Hindu Kush Mountains of the Upper Indus Basin (UIB) have been analyzed for seasonal and annual trends over the period 1961–2000 and compared with neighboring mountain regions and the Indian subcontinent. Strong contrasts are found between the behavior of winter and summer temperatures and between maximum and minimum temperatures.Winter mean and maximum temperature show significant increases while mean and minimum summer temperatures show consistent decline. Increase in diurnal temperature range (DTR) is consistently observed in all seasons and the annual dataset, a pattern shared by much of the Indian subcontinent but in direct contrast to both GCM projections and the narrowing of DTR seen worldwide. This divergence commenced around the middle of the twentieth century and is thought to result from changes in large-scale circulation patterns and feedback processes associated with the Indian monsoon.

The impact of observed seasonal temperature trend on runoff is explored using derived regression relationships. Decreases of [about] 20% in summer runoff in the rivers Hunza and Shyok are estimated to have resulted from the observed 1°C fall in mean summer temperature since 1961, with even greater reductions in spring months. The observed downward trend in summer temperature and runoff is consistent with the observed thickening and expansion of Karakoram glaciers, in contrast to widespread decay and retreat in the eastern Himalayas. This suggests that the western Himalayas are showing a different response to global warming than other parts of the globe.”

There is also the issue of the attribution of the glacier melt. The Economist article writes that

“The glacier is a dirty brown colour….it looks more like an enormous mudslide than a frozen reservoir of fresh water”.

In a recent paper that is weblogged on Climate Science at

New Paper Elevates The Role Of Black Carbon In Global Warming

V. Ramanathan was quoted in news release with respect to their March 23 in Nature Geoscience titled “Global and regional climate changes due to black carbon” that

 ”‘We now have to examine if black carbon is also having a large role in the retreat of arctic sea ice and Himalayan glaciers as suggested by recent studies.’”

Thus, despite the high expectation of quality articles from the Economist, with respect to the topic area of climate change, they are clearly biased and misleading in their coverage.

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Holland Inundated by Alarmist Propaganda: A Guest Weblog By Hendrik Tennekes

Guest weblog by Hendrik Tennekes


Five months ago, I felt that the tide in Holland was turning. Marcel Stive, a civil engineering professor and member of the Delta Committee, a blue-ribbon panel that was going to publish a report on our coastal defenses, said in an interview with an alumni magazine:


“Fortunately, the time rate of climate change is slow compared to the life span of the defense structures along our coast. There is enough time for adaptation. We should monitor the situation carefully, but up to now climate change does not cause severe problems for our coastal defense system. IPCC has given lower estimates for the expected sea level rise in four successive reports.” (I quoted this in my weblog of 14 July 2008).


But what happened? The Delta Committee published its report in September, and based its recommendations on well over a meter of sea-level rise in this century and a tenfold increase in coastal security. Its estimate for the additional funding needed is two billion dollars annually.


In interviews with journalists, scientists associated with the Delta Committee went further yet. Professor Pavel Kabat of Wageningen University said that sea-level rise could easily exceed the number given in the report, and Professor Pier Vellinga, also of Wageningen University, quoted six meters, on the assumption that the rate at which the Greenland ice cap is melting will accelerate dramatically.


Professor Hans von Storch, a German member of the subcommittee in charge of assessing the scientific evidence, promptly protested in the Dutch press, saying that the Delta Committee had piled extreme upon extreme in order to obtain these figures. Holland’s senior science writer, Karel Knip, followed suit, suggesting that the Committee was evidently ignorant of the statistics of rare events. For reasons unknown to me, KNMI, the Royal Netherlands Meteorological Institute, did not attempt a rebuttal. It could have chosen to state in public that recent assessments by IPCC and by its own scientists predicted half a meter of sea-level rise, but it didn’t. I suspect that the Department of Transportation and Public Works, which is responsible for our coastal defense system, instructed KNMI not to derail the political debate with a balanced presentation of the scientific evidence.


Much to my dismay, the publication of the Committee report was followed by a massive publicity campaign. Al Gore came over to Holland a month ago, and gave a $300,000 speech blasting the energy industry. James Hansen, advisor to Gore and well-known forecaster of catastrophic sea-level rise, will address a meeting in Rotterdam next month. Kabat and Vellinga will speak there too. The Urgenda Foundation, not so subtly named for its promotion of an Urgent Agenda for Climate Change, has published a manifesto full of hell and damnation in a leading newspaper. After several years of floating scary stories about possible inundation of Amsterdam Airport, Professor Vellinga now advocates a massive dam in front of our entire coast, wide enough for urban development.


What is the purpose of hyped-up forecasts of sea-level rise? Why don’t the Dutch participants in IPCC speak up? Why doesn’t the IPCC brass? Whose interests are served by ridiculous climate alarms? The problems surrounding climate change are tough enough as is. We desperately need moderation, not propaganda.

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New Article On The Need To Move From Dubious Multi-Decadal Regional Climate Predictions To The Assessment of Regional Vulnerabilites

 The Colorado Foundation for Water Education is a statewide non-profit, non-advocacy organization providing water resource information and education. They publish invaluables report on Colordao (and western USA) water issues.

They have just released the latest in their Citizen’s Guide series which is titled Citizen’s Guide to Colorado Climate Change. The Guide was authored by multiple experts in the field, and contains details on current climate change research in Colorado. While there is a long article on the prediction of Colorado climate decades into the future (which Climate Science and others have concluded have no skill), I was invited to write a short article for the publication. It is titled Global Climate Models: Many Contributing Influences and is reproduced below. My article questions the value of the multi-decadal regional climate model predictions as the primary information to provide to policymakers.

 Pielke Sr., R.A., 2008: Global climate models – Many contributing influences. Citizen’s Guide to Colorado Climate Change, Colorado Climate Foundation for Water Education, pp. 28-29

The full magazine can be viewed at

“The historical climate of Colorado illustrates major floods and extended periods of drought. Extreme cold and warmth have also always been a part of Colorado weather. In terms of water resources, the state has faced extended periods of drought, as well as years of generous water supply. On the longer time period, as illustrated in Figure 1, periods of extreme drought and wet periods have been even more pronounced than in the historical record of the last century and the late 1800s.

This figure, from a study led by researchers at the University of Arizona, uses tree rings to extend precipitation data back to well before humans directly measured rain and snow. In this data set, for Lee Ferry along the Colorado River, severe droughts lasting decades, such as one in the 12th century, are clearly evident. In the period of around 800 AD to 2004 AD, for example, there was a period of 25 years with 87 percent less precipitation than in the 1906 to 2004 mean.

Excessively dry periods occurred without any significant interference of humans in the climate system. Multidecadal global model predictions of the climate in Colorado actually present a less serious threat to the state’s water supply than if one of the extended past droughts reoccurred.

An assumption that projecting climate is easier than predicting weather is not correct, in my view. No global model has been able to replicate and explain the large natural variations in climate that are evident in Figure 1. In reality, the climate is highly nonlinear, in which the effect on the climate system from forcings is often episodic and abrupt, rather than slow and gradual. Large, long term variations in regional climate are the norm, as illustrated in Figure 1. The human effect on the climate system through such forcings as added CO2, land use change, and the input of pollution particles from fires, vehicles and industrial activity, only add to the complexity of the climate system response.

Moreover, water resources are affected by a variety of human and natural effects beyond long term climate variability and change, as illustrated in Figure 2. These effects also interact with each other in complex nonlinear ways.

We therefore need a new approach. A way forward with respect to more effective water resource policies is to focus on the assessment of adaptation and mitigation strategies that reduce the vulnerability of Colorado water resources to both natural and human caused climate variability and change, as well as all other threats. Effective adaptation strategies include developing environmentally sensitive way to accumulate water during wetter than average periods and building the infrastructure to transport water across large distances. They reduce the state’s vulnerability to periods of drought, regardless of how climate changes naturally and in response to human climate forcings in the coming decades.

This framework for a vulnerability assessment of Colorado water resources focuses on the water required for the state’s economic, social and environmental activities. This is in contrast to the GCM-focus of multidecadal global model predictions downscaled to Colorado. A top-down approach from a global perspective, in which the skill is dependent on the forecast accuracy of these global models offers a much smaller set of future scenarios for Colorado than are actually possible.

The vulnerability focus permits a much more comprehensive framework to assess threats to Colorado’s water resources. Variability and changes in the climate are just one threat to water resources. The current climate models present only a subset of the possible risk, even from climate variability and change.

The vulnerability approach uses water resource specific models and observations to determine the thresholds at which negative effects occur with the state’s water supplies. Using mitigation and adaptation, we need to prevent crossing the thresholds. A vulnerability perspective, focused on regional and local societal and environmental resources, is a more inclusive, useful and scientifically robust framework to use with policymakers. In contrast to the limited range of possible future risks by current climate models, the vulnerability framework permits the evaluation of the entire spectrum of risks to the water resources associated with all social and environmental threats, including climate variability and change.”

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Adaptation to Climate Change in the Desert Southwest Conference

There is going to be a meeting entitled “Adaptation to Climate Change in the Desert Southwest”  on  January 22-23, 2009 at the  Westward Look Resort in Tucson Arizona [thanks to Ben Herman for alerting us]. The announcement for the meeting reads

“The University of Arizona  is hosting a climate change conference sponsored by the Institute for the Study of Planet Earth, James E. Rogers College of Law, Climate Assessment for the Southwest, and the Program on Economics, Law, and the Environment.”

The meeting description reads

“Scientists predict that climate change will exact a heavy toll upon the southwestern United States regardless of what is done to reduce greenhouse gas emissions. As a result, the southwestern United States is a test case for climate scientists, economists, lawyers, policymakers and national, state, tribal and community leaders across the nation. This conference will explore how we can adapt to these changes in a manner that reduces the environmental and social costs of climate change. Specifically, what can we do now to maximize the potential for a sustainable southwestern natural and human habitat? Join an outstanding group of scientists, scholars, and national and regional community leaders to take a hard look at one of the most powerful questions of our time: what will climate change mean for the southwest?  The keynote speaker is the 2005 Nobel Prize Laureate in Economics, Thomas Schelling.”

This meeting, unfortunately, perpetuates the claim that “Scientists [can skillfully] predict …[regional] climate change”.  The meeting is already prejudiced in that there will be no scientists who present the perspective that regional climate change in response to human activities cannot yet be skillfully predicted. Climate Science has frequently discussed the limitations of such regional climate predictions; e.g. see

The Publication Of A Hypothesis: An Article Titled “A Model Forecast – Model Projections of an Imminent Transition to a More Arid Climate in Southwestern North America”

Such meetings, as to be held in Tucson in January 2009, need to be recognized as biased presentations of the science. As a result, the adaptation concepts that are presented will necessarily be incomplete and could result in unintended negative consequences.

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Climate Science Overstatement By Bob Schieffer In the Final Presidential Debate

At the last McCain/Obama debate, Bob Schieffer had the following question:

“SCHIEFFER: Let’s go to — let’s go to a new topic. We’re running a little behind.

Let’s talk about energy and climate control. Every president since Nixon has said what both of you…

MCCAIN: Climate change.

SCHIEFFER: Climate change, yes — has said what both of you have said, and, that is, we must reduce our dependence on foreign oil.”

This question illustrated the hubris that is driving the emphasis on major policy actions on climate. This is that humans can “control” climate (i.e. Schieffer said “Let’s talk about …..climate control“). 

The IPCC’s perspective, that the dominate human climate forcing is its addition of carbon dioxide to the atmosphere and that natural fluctuations in climate are significantly smaller than this human climate forcing, perpetuates the erroneous perspective that we can control the climate.  The news media, as exemplified by Bob Schieffer, is simply picking up this theme.

We discuss the overselling of weather modification in our book

Cotton, W.R. and R.A. Pielke Sr., 2007: Human impacts on weather and climate, Cambridge University Press, 330 pp.

We show in our book how the extravagant claims of what could achieved with weather modification were used to sell programs to deliberately change the weather. When most of these claims could not be scientifically substantiated, the credibility of this field of meteorology fell into disrepute.

With the claims that we can control climate with such efforts as geoengineering (e.g. see), the IPCC scientists are falling into the same trap. Climate is an even more complex system than the weather by itself.


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Filed under Climate Science Reporting

Synoptic Weather Lab Notes Available

For over 25 years, I taught a course on synoptic weather analysis and forecasting (for an example of my course syllabus;see). As part of that course, I completed a set of notes that might be of use to others. Dallas Staley has graciously scanned them and placed the notes on our research website. They are available at

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

The Table of Contents is given on pages ii-iii. Quiz and Exams are presented in the Appendices.

The relevance to climate, of course, is that it is the synoptic weather features which result in the weather that we experience and which effects social and environmental resources, not a global average surface temperature anomaly.  Long term changes in synoptic weather features are required in order to result in long term climate change.

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A New Paper “Ensemble Re-Forecasts Of Recent Warm-Season Weather: Impacts Of A Dynamic Vegetation Parameterization” By Beltan-Przekurat Et Al 2008

Our paper on the value added in seasonal weather prediction as a result of adding a dynamic vegetation parameterization has appeared. The paper is

Beltran-Przekurat, A., C. H. Marshall, and R. A. Pielke Sr. (2008), Ensemble re-forecasts of recent warm-season weather: impacts of a dynamic vegetation parameterization, J. Geophys. Res., doi:10.1029/2007JD009480, in press.

The abstract reads

“The impact of dynamic vegetation on ensemble re-forecasts of recent warm-season weather over the continental U.S. was assessed using the Regional Atmospheric Modeling System (RAMS) and a fully coupled dynamic vegetation version of RAMS, the General Energy and Mass Transfer–RAMS (GEMRAMS). Two 10-member ensembles were produced for the June-August periods of 2000 and 2001. For each period, one of the members used the standard RAMS, and the other the GEMRAMS version. Initial and lateral boundary conditions were provided by a reforecast produced with the NCEP Seasonal Forecast Model (SFM). In addition, a pair of “baseline” simulations was produced using the NCEP Reanalysis, the “perfect” global forecast, as initial and lateral boundary conditions. Precipitation in the regional ensembles was largely controlled by the driving large-scale forcing. A large precipitation bias exists over the regional domain in the SFM itself that is amplified in the simulations. For the time periods and model setup considered in this work, under an explicitly predictive model configuration, the use of a more complex parameterization of land-surface processes with dynamic vegetation added little value to the skill of the seasonal forecast over the regional domain. This is a consequence of the strong dependence of the regional model results on the lateral boundary conditions provided by the parent global model. Even the use of an ensemble of predictions does not remove all of the biases that are inherent in the parent global model.”

This paper reinforces two issues that have been repeatedly emphasized on climate science and elsewhere:

1. Adding additional real-world complexity to weather and climate prediction models makes skillful forecasts more difficult. If this difficulty is so serious with respect to seasonal weather predictions, it will be even more so for multi-decadal global climate predictions.

2. The regional models cannot correct for biases (i.e. errors) in the parent global model. Regional dynamic model downscaling based on output from parent models (such as the IPCC multi-decadal projections) cannot add predictive skill over and beyond what is already present in the parent model. If the parent model (e.g. an IPCC simulation) does not have all of the climate forcings and feedbacks that are important on multi-decadal climate time scales, the regional model cannot correct for these shortcomings.

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Filed under Climate Change Forcings & Feedbacks, Climate Models

Comments On The Plan To Declare Carbon Dioxide as a Dangerous Pollutant

The weblogs ICECAP and Watts Up With That have alerted us to the plan to list carbon dioxide as a pollutant by the EPA where they report on an article titled “Obama to Declare Carbon Dioxide Dangerous Pollutant” by Jim Efstathiou Jr. of Bloomberg.

Climate Science has weblogged on this subject in the past; see

Will Climate Effects Trump Health Effects In Air Quality Regulations?

Supreme Court Rules That The EPA Can Regulate CO2 Emissions

Science Issues Related To The Lawsuit To The Supreme Court As To Whether CO2 is a Pollutant

What the listing of carbon dioxide as a pollutant would do is to implicitly declare that any human activity that affects climate could be considered a pollutant. This would logically mean, for instance,  that the EPA could regulate land use since, as extensively documented in the peer reviewed literature (e.g. see), landscape change is a human climate forcing.

This plan to regulate CO2 as a pollutant (since it is a human climate forcing) would give them the legal rationale to permit the implementation of additional federal regulations for other human climate forcings including the zoning of how land is developed.  Everyone should realize the implications and significance of this potential expansion of federal authority.  There may be societal benefits to such broad climate regulation authority, however, this issue should be more effectively discussed and debated than it has been up to the present.

UPDATE: It has been pointed out to me that the EPA does not have the “legal” rationale (i.e. precedent or law) to permit the  implementation of additional federal regulations for other human climate forcings. Hence, I have removed”legal” (by the strike out).

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Filed under Climate Change Regulations, Climate Science Op-Eds