Monthly Archives: October 2010

New Paper “Numerical Simulations Of The Impacts Of Land-Cover” By Kala Et Al 2010

There is an important, well written new paper that documents the role of land-cover on synoptic weather features; in this case cold fronts. The paper is

J. Kala, T. J. Lyons, and U. S. Nair, 2010: Numerical Simulations of the Impacts of Land-Cover Change on Cold Fronts in South-West Western Australia. Boundary-Layer Meteorol DOI 10.1007/s10546-010-9547-3

The abstract reads

“The south-west of Western Australia has experienced significant land-cover change as well as a decline in rainfall. Given that most precipitation in the region results from frontal passages, the impact of land-cover change on the dynamics of cold fronts is explored using the Regional Atmospheric Modeling System version 6.0. Frontal simulations are evaluated against high resolution atmospheric soundings, station observations, and gridded rainfall analyses and shown to reproduce the qualitative features of cold fronts. Land-cover change results in a decrease in total frontal precipitation through a decrease in boundary-layer turbulent kinetic energy and vertically integrated moisture convergence, and an increase in wind speed within the lower boundary layer. Such processes contribute to reduced convective rainfall under current vegetation cover.”

The conclusion has the text at the end

“Sensitivity tests are carried out to investigate effects of historical land-cover change and it is found that land-cover change results in a decrease in precipitation for both fronts, with a higher decrease for the summer front. The decrease in precipitation is attributed to a decrease in TKE [turbulent kinetic energy] and moisture flux convergence as well as an increase in wind speed within the lower boundary layer. The suggested mechanism is that the enhanced vertical mixing under pre- European vegetation cover, with the decrease in wind speeds close to the ground, enhances microphysical processes leading to increased convective precipitation. The higher decrease in precipitation for the summer front is most likely due to enhanced convection during summer.

Whilst this study was limited to two events, it highlights a significant change in microphysical processes caused by land-cover change. Even without large-scale shifts in the climate, local land-use practices affect atmospheric processes and need to be adequately managed under a changing climate.”

This is another research study with recommendations regarding the diversity of human climate forcings beyond CO2 which the next IPCC assessment must include, if it is going to be a credible evaluation of climate science.

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Comments On An NSF Webcast On “Will Clouds – The Wild Card of Climate Change – Speed Or Slow Warming?” By David A. Randall

There is a webcast Thursday October 28 2010 titled “NSF Webcast for  Reporters: Will Clouds–the Wild Card of Climate – Speed Or Slow Warming?” by David Randall of Colorado State University (h/t to Joe D’Aleo). Randall was one of the two convening lead authors of Chapter 8 on Climate Models and their Evaluation in the 2007 IPCC report, and has been selected as one of the two convening lead authors of Chapter 7 on Clouds and Aerosols for the next IPCC assessment.

I raise two issues in this post with respect to this webcast.

1.  Clouds are not the only “wild card” as implied by the title of his talk.  For example, Chapter 8 of the 2007 IPCC report, which Randall was one of the two convening lead authors, was not a balanced  assessment of climate models. As I wrote in

Pielke, R.A. Sr., 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.

Chapter 8 of the IPCC Report is …. poorly written on this subject where while they write

“Evaluation of the land surface component in coupled models is severely limited by the lack of suitable observations. The terrestrial surface plays key climatic roles in influencing the partitioning of available energy between sensible and latent heat fluxes, determining whether water drains or remains available for evaporation, determining the surface albedo and whether snow melts or remains frozen, and influencing surface fluxes of carbon and momentum. Few of these can be evaluated at large spatial or long temporal scales. This section therefore evaluates those quantities for which some observational data exist”

they fail to identify the rich peer-reviewed literature on this subject but only provide a very limited presentation on this subject in the Chapter.

Indeed, while land processes are discussed in the Report, the focus is on its role in the carbon budget and in its effect on the global average radiative forcing.

To document missing papers….. we have cross-referenced Climate Science with the IPCC WG1 Report on just one aspect of the above two topics (regional radiative forcing and nonradiative forcing), namely the role of land use change within the climate system [see the Appendix in the section Documentation Of IPCC WG1 Bias by Roger A. Pielke Sr. and Dallas Staley - Part II in Pielke 2008].

The highlighting by the NSF of the IPCC finding in the Workshop announcement for David Randall’s presentation that

“Clouds are “the largest  source of uncertainty” in projections of climate change, according to  the Intergovernmental Panel on Climate Change (IPCC)”

perpetuates the narrow view of the IPCC that

“Although the natural causes of climate variations and changes are undoubtedly important, the human influences are significant and are dominated by the emissions into the atmosphere of greenhouse gases, the most important of which is CO2. The adverse impact of these gases on regional and global climate constitutes the primary climate issue for the coming decades.”

which is refuted in our article

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.

The only robust, non-refuted hypothesis, as we show in our article, is that

“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 concern during the coming decades.”

I agree with David Randall that clouds are a wild card in the assessment of climate variability and long term change. However, there are quite a few “wild cards” including the diverse range of effects of aerosols, of land use-land cover change, and of natural effects, all of which remain incompletely represented in the multi-decadal global climate models. David Randall failed to include this broader perspective when he was convening lead author of Chapter 8 in the 2007 IPCC report, and appears to be persisting in this narrow view.

2. My second issue is that the NSF comes across as an advocate for a particular perspective (i.e. that there is a main”wild card”) without presenting to reporters that there are other scientifically sound viewpoints in the climate science community.

The NSF is already funding research which compromises the scientific method; e.g. see

The National Science Foundation Funds Multi-Decadal Climate Predictions Without An Ability To Verify Their Skill

I urge reporters and others who participate in this webcast ask questions on other “wild cards” in the understanding and assessment of the predictability of the climate system.

The e-mail announcement for their webcast is reproduced below

From:  Whiteman, Lily M [mailto:lwhitema@nsf.gov]
Sent: Thursday, October 21, 2010 9:58  AM
To: Whiteman, Lily  M
Subject: NSF Webcast for  Reporters: Will Clouds–the Wild Card of Climate Change- Speed or Slow  Warming?
This  is an automated e-mail. Please do not respond to this  message.
National Science  Foundation
4201  Wilson Blvd., Arlington,  VA 22230
“Where Discoveries  Begin”

For  Immediate Release
10/20/2010
Media  Contact:
Lily Whiteman, NSF, (703)  292-8310,  _lwhitema@nsf.gov_
(mailto:lwhitema@nsf.gov)
_LIVE,  INTERACTIVE WEBCAST FOR REPORTERS: WILL CLOUDS–THE WILD CARD OF CLIMATE  CHANGE–SPEED OR SLOW WARMING?_
(http://www.nsf.gov/news/news_summ.jsp?cntn_id=117748)
NSF invites media to participate in a webcast  briefing on Thursday, Oct. 28 at 1:00 p.m.,  EDT

Cloud behavior will  help determine how warm the planet becomes as climate change  continues.
Credit:  Kristina Rebelo
_Credit  and Larger  Version_
(http://www.nsf.gov/news/news_images.jsp?org=NSF&cntn_id=117748)
Clouds are “the largest  source of uncertainty” in projections of climate change, according to  the Intergovernmental Panel on Climate Change (IPCC). This uncertainty  arises because different types of clouds exert different forces on  climate: Some clouds help cool the Earth and some clouds help warm it.  So far, no one knows which effect will win out as the climate continues to change. This uncertainty begs some  of the most critical (and most fascinating) questions about climate  change: Will clouds help speed or slow global warming? Why is cloud  behavior so difficult to predict? And, in the midst of such uncertainty  about clouds, how in the world are scientists learning to project the  behavior of these ephemeral, ever-changing, high-altitude  phenomena? To help give the role  of clouds in climate change its due, the National Science Foundation  (NSF) will host a webcast with a leading authority on clouds and climate  change: David Randall, director of the Center for Multiscale Modeling of  Atmospheric Processes and a professor of atmospheric science at  Colorado  State University. The webcast will be  held on Thursday, Oct. 28 at 1:00 p.m.,  EDT.

Following the webcast, NSF  will release a multi-media package about clouds and climate change  titled, “Clouds: The Wild Card of Climate Change.” This package–which will provide a wealth of information to reporters,  policy makers, scientists, educators, the public and students of all  levels–will be posted on NSF’s website at _http://www.nsf.gov/news/special_reports/_
(http://www.nsf.gov/news/special_reports/) .

Who: Cloud and  climate change expert David Randall, director of the Center for Multiscale Modeling of Atmospheric Processes and a professor of atmospheric science at Colorado State University.
What: A media  briefing via teleconference and webcast to discuss why clouds are the wild card of climate  change.
When: Thursday, Oct. 28, at 1:00 p.m.,  EDT. How to  Participate: Reporters in the  United  States may participate by teleconference or Internet. To participate by teleconference, call (888) 603-7924. Passwords are needed to access the presentation and to  ask questions during the live event.  To obtain the password to  participate in the teleconference and to obtain the URL and password to  access the webcast, e-mail
Lily Whiteman at _lwhitema@nsf.gov_ (mailto:lwhitema@nsf.gov) . Before and
during  the event, e-mail questions for David Randall at  webcast@nsf.gov.
######
NSF-MA  10-027
The National Science Foundation (NSF) is an  independent federal agency that supports fundamental research and education  across all fields of science and engineering. In fiscal year (FY) 2010, its  budget is about $6.9 billion. NSF funds reach all 50 states through grants to  nearly 2,000 universities and institutions. Each year, NSF receives over  45,000 competitive requests for funding, and makes over 11,500 new funding  awards. NSF also awards over $400 million in professional and service  contracts yearly.

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Paper ” Evidence Of Enhanced Precipitation Due To Irrigation Over The Great Plains Of The United States” By DeAngelis Et Al 2010

I mentioned this paper last week  [h/t to Faisal Hossain] but want to discuss further today. The paper is

DeAngelis, A., F. Dominguez, Y. Fan, A. Robock, M. D. Kustu, and D. Robinson (2010), Evidence of enhanced precipitation due to irrigation over the Great Plains of the United States, J. Geophys. Res., 115, D15115, doi:10.1029/2010JD013892.

“At the end of World War II, there was a rapid increase in irrigation over the Ogallala Aquifer in the Great Plains of the United States via groundwater withdrawal, and we hypothesize that this disruption of the local hydrological cycle has enhanced the regional precipitation. We examined station and gridded precipitation observations for the warm season months over and downwind of the Ogallala over the 20th century. Increases in precipitation of 15–30% were detected during July from the easternmost part of the aquifer to as far downwind as Indiana. The timing (1940s, July) and spatial pattern of the precipitation increase are consistent with the history of Ogallala irrigation and mechanisms by which increases in evapotranspiration can affect convection. Additionally, we conducted a vapor tracking analysis and found that evapotranspiration over the Ogallala Aquifer contributes to downwind precipitation and that the contribution is greater when the evapotranspiration is higher. This makes it hydrologically possible that the irrigation development was associated with the observed precipitation increases. Finally, there is no clear evidence that atmospheric circulation changes or modes of internal climate variability increased the July precipitation. Further analysis of the influence of Ogallala irrigation on precipitation will include the controlled analysis of climate model simulations that explicitly include irrigation.”

Text from the paper includes

“The effect of this human alteration of the natural water cycle on regional precipitation over this area is the subject of this study. We hypothesize that the increase in irrigation over the 20th century resulted in a detectable enhancement of precipitation over the Great Plains. An analysis of long‐term precipitation observations and simulations is combined with wind observations and vapor transport analysis to search for the link between irrigation and increases in precipitation over the region.

The mechanisms linking increased irrigation and enhancement of precipitation are most likely related to the effects of increased ET on precipitable water and convection over this region. The possibility of convection being influenced by irrigation is supported by the fact that most irrigation over the Ogallala occurs in July and August (Figure 1c) when more than 80% of precipitation originates from thunderstorms [Changnon, 2001]. Convection is associated with the convective available potential energy (CAPE) of the atmosphere, which increases with warmer and moister lower tropospheric conditions. Higher values of CAPE make convection more likely when synoptic conditions are favorable for convection, or can be the difference between convection and no convection if synoptic conditions are borderline favorable [Barnston and Schickedanz, 1984; De Ridder and Gallée, 1998]. It follows that if irrigation influences lower troposphere temperature and moisture, it will impact CAPE and therefore convective precipitation.”

This excellent research contribution illustrates why fossil water irrigation introduces another additional human climate forcing that was not assessed in the 2007 IPCC reports.

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News Article “

There was a news article today in the Boulder Camera by Laura Snider titled

Boulder scientists: Space tourism could contribute to climate change

The article includes the text

“The researchers found that the soot, or “black carbon,” created by 1,000 launches a year — the frequency promised by 2020 in some promotional materials for the space tourism industry — could cause temperatures in Antarctica to warm by as much as 1.5 degrees.

The team of three researchers — Michael Mills of the National Center for Atmospheric Research, Darin Toohey of the University of Colorado and Martin Ross of The Aerospace Corp. in Los Angeles — will publish their findings in the journal Geophysical Research Letters.

The potential impact of the black carbon in the rocket exhaust is magnified because the pollutant would be deposited miles above the surface of the Earth.”

The entire article is worth reading. See also the post

 “Limits On The Space Launch Market Related To Stratospheric Ozone Depletion” By Ross et al. 2009

This is a new human climate forcing that would be added to an already diverse range of human climate forcings as reported in NRC (2005).

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Comments On An ECMWF New Report On Surface Wind Trends

There is a recent study by ECMWF [the European Centre for Medium Range Forecasts] on long-term trends in surface winds - h/t to  Paolo Mezzasalma.

The news report on the study is titled

Wind stilling over the continents of the Northern hemisphere in the last 30 years

The article starts with the text [bold face added]

“A study published on 17 October 2010 in the journal Nature Geoscience shows that over the past three decades, surface wind speeds seem to have noticeably decreased in several regions of the world, such as the United States, China, Australia, and in several European countries. Given the often inadequate quality and heterogeneity of wind data measured by anemometers, no long-term study of the evolution of wind speeds on a global scale had been carried out so far.

 

However, after a detailed and thorough statistical analysis of the inconsistencies of wind measurements taken at 5412 stations resulting in the rejection of 85 % of them, an analysis of the remaining data revealed a major trend: over most land surfaces  of the Northern hemisphere mid latitudes, winds have decreased (see figure below). The study was carried out jointly by the Laboratoire des Sciences du Climat et de l\u2019Environnement (LSCE) and the European Centre for Medium-Range Weather Forecasts (ECMWF). It also shows that over Asia, moderate to strong winds  have decreased most rapidly.”

This study also attempts an explanation of the reasons for this decrease. Using a variety of data (datasets from reanalyses carried out by ECMWF or other smaller scale simulations, satellite and radiosonde observations), the authors show that this decrease in surface wind speed can be largely explained by an increase in vegetation and, to a smaller extent, by changes in the general atmospheric circulation over the past few decades.

Since, wind speed affects the vertical mixing of heat, this study implies there will be an effect on the surface temperature trends at these locations also. Most, or all, of these sites presumably are where  surface temperatures, used as part of the construction of a global annual average surface temperature trend, are obtained.

The study also documents that the surface landscape changes at these sites sufficiently to alter the winds. They write “the authors show that this decrease in surface wind speed can be largely explained by an increase in vegetation and, to a smaller extent, by changes in the general atmospheric circulation over the past few decades.” 

Such an increase in vegetation would also alter the temperatures. We have assessed this issue for locations in Colorado in our paper

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.

The abstract of our paper reads [boldfaced added]

“A daily 850–700 mb layer mean temperature, computed from the National Center for Environmental Prediction-National Center for Atmospheric Research (NCEP-NCAR) reanalysis, and satellite-derived greenness values, as defined by NDVI (Normalised Difference Vegetation Index), were correlated with surface maximum and minimum temperatures at six sites in northeast Colorado for the years 1989–98. The NDVI values, representing landscape greenness, act as a proxy for latent heat partitioning via transpiration. These sites encompass a wide array of environments, from irrigated-urban to short-grassprairie. The explained variance (r2 value) of surface maximum and minimum temperature by only the 850–700 mb layer mean temperature was subtracted from the corresponding explained variance by the 850–700 mb layer mean temperature and NDVI values. The subtraction shows that by including NDVI values in the analysis, the r2 values, and thus the degree of explanation of the surface temperatures, increase by a mean of 6% for the maxima and 8% for the minima over the period March–October. At most sites, there is a seasonal dependence in the explained variance of the maximum temperatures because of the seasonal cycle of plant growth and senescence. Between individual sites, the highest increase in explained variance occurred at the site with the least amount of anthropogenic influence. This work suggests the vegetation state needs to be included as a factor in surface temperature forecasting, numerical modeling, and climate change assessments.”

This another reason why there is a divergence between surface and lower tropospheric temperatures as we identified 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.

The finding by ECMWF that there is long-term trend in wind speeds that is “largely explained by an increase in vegetation“, supports the conclusion of significant effects on the assessment of the global  annual land average surface temperature trend that are the result of effects other than warming (or cooling) of the remainder of the troposphere.

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Recommended Reading – A Repost Of “Heresy And The Creation Of Monsters” By Judy Curry

Kudos to Judy Curry for a very valuable post on the Scientific American article “Climate Heretic: Judith Curry Turns on Her Colleagues” and on the follow-up survey by Michael Lemonick.

Judy’s post is titled

 Heresy and the creation of monsters

One extract from her post succinctly provides the reason she has become engaged in the climate science and IPCC discussion (and is a viewpoint that I share). She writes

“this is my carefully considered choice on what it means to be a scientist and to behave with personal and professional integrity.”

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Misleading Text In A Scientific American Article That Judy Curry Is A “Climate Heretic”

I was very disappointed to read erroneous information, in an otherwise very informative article, in the Scientific American by Michael D. Lemonick titled

Climate Heretic: Judith Curry Turns on Her Colleagues

which seeks to isolate Judy Curry as being an outlier from her climate science colleagues [the article, of course, is useful in that it does expose the attempt by some to marginalize anyone who differs from the IPCC viewpoint, and Michael Lemonick is commended for doing that].

The text in his article, however, includes the header of one of its sections which implies she is gone

Over to the Dark Side“.

An excerpt from the article includes the text (referring to one of the IPCC reports)

“Apparently few others felt the same way [as Judy]; of the many hundreds of scientists involved in that report, which came out in 2001, only a handful have claimed their views were ignored—although the Third Assessment Report could not possibly reflect any one scientist’s perspective perfectly.”

This science reporter is incorrect in this view.

 Judy Curry is hardly a “climate heretic” but rather, as an internationally well-respected climate scientist, is providing a much needed healthy, independent examination of the IPCC assessment and finding it has significant shortcomings. Judy’s scientific credentials are outstanding; e.g. see her google scholar citations http://scholar.google.com/scholar?hl=en&as_sdt=40000&q=judy+curry.

I agree with her in this conclusion and have documented evidence for this, for example, in

Pielke, R.A. Sr., 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

 She and I are not alone in these findings

As just a few examples, I list below multi-authored peer reviewed papers and one NRC assessment that present views that materially differs from that presented in the 2007 IPCC assessment. Some of the co-authors are contributors to the 2007 IPCC report, but in the articles presented below and  in the 2005 NRC assessment report, they agreed with the conclusions that were reached in these papers. These conclusions  document the need for a broader perspective to the role of human and natural climate forcings and feedbacks than just a CO2-centric view. 

Examples of Papers With Evidence of Viewpoints on Climate Science Ignored or Underreported in the 2007 IPCC reports.   [bold face added in the text below]

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. {Note that each author is a Fellow of the American Geophysical Union]

with the conclusions including that

The evidence predominantly suggests that humans are significantly altering the global environment, and thus climate, in a variety of diverse ways beyond the effects of human emissions of greenhouse gases, including CO2. Unfortunately, the 2007 Intergovernmental Panel on Climate Change (IPCC) assessment did not sufficiently acknowledge the importance of these other human climate forcings in altering regional and global climate and their effects on predictability at the regional scale. It also placed too much emphasis on average global forcing from a limited set of human climate forcings. Further, it devised a mitigation strategy based on global model predictions. For example, although aerosols were considered as a global average forcing, their local effects were neglected (e.g., biomass burning, dust from land use/land cover management and change, soot from inefficient combustion).”

McAlpine, C.A., W.F. Laurance, J.G. Ryan, L. Seabrook, J.I. Syktus, A.E. Etter, P.M. Fearnside, P. Dargusch, and R.A. Pielke Sr. 2010: More than CO2: A broader picture for managing climate change and variability to avoid ecosystem collapse. Current Opinion in Environmental Sustainability, in press

with the abstract

“Climate change policies currently focus on reducing the concentration of industrial atmospheric greenhouse gases due to burning fossil fuels and deforestation, but pay limited attention to feedbacks between the land surface and the climate system. In tropical and subtropical regions, forests and woodlands play an important role in the climate system by buffering climate extremes, maintaining the hydrological cycle and sequestering carbon. Despite the obvious significance of these feedbacks to the functioning of the climate system, deforestation continues apace. It is critical, therefore, that a broader focus be developed that includes the restoration of feedbacks between vegetation and climate. In this paper, we present a synthesis of the best available, policy-relevant science on the feedbacks between the land surface and the climate system, with a focus on tropical and sub-tropical regions. Based on this science, we argue for a stronger integration of land-use and climate-change policies. These policies need to include a virtual halt to all deforestation and an acceleration of investment in strategic reforestation, supported by a comprehensive global forest monitoring program. Without these actions, the degradation of the Earth’s ecosystems will become exacerbated as their resilience is eroded by accelerated changes in temperature, precipitation and extreme weather events.”

Rial, J., R.A. Pielke Sr., M. Beniston, M. Claussen, J. Canadell, P. Cox, H. Held, N. de Noblet-Ducoudre, R. Prinn, J. Reynolds, and J.D. Salas, 2004: Nonlinearities, feedbacks and critical thresholds within the Earth’s climate system. Climatic Change, 65, 11-38.

with the abstract

“The Earth’s climate system is highly nonlinear: inputs and outputs are not proportional, change is often episodic and abrupt, rather than slow and gradual, and multiple equilibria are the norm. While this is widely accepted, there is a relatively poor understanding of the different types of nonlinearities, how they manifest under various conditions, and whether they reflect a climate system driven by astronomical forcings, by internal feedbacks, or by a combination of both. In this paper, after a brief tutorial on the basics of climate nonlinearity, we provide a number of illustrative examples and highlight key mechanisms that give rise to nonlinear behavior, address scale and methodological issues, suggest a robust alternative to prediction that is based on using integrated assessments within the framework of vulnerability studies and, lastly, recommend a number of research priorities and the establishment of education programs in Earth Systems Science. It is imperative that the Earth’s climate system research community embraces this nonlinear paradigm if we are to move forward in the assessment of the human influence on climate.”

Pielke Sr., R.A., G. Marland, R.A. Betts, T.N. Chase, J.L. Eastman, J.O. Niles, D. Niyogi, and S. Running, 2002: The influence of land-use change and landscape dynamics on the climate system- relevance to climate change policy beyond the radiative effect of greenhouse gases. Phil. Trans. A. Special Theme Issue, 360, 1705-1719

with the abstract

“Our paper documents that land-use change impacts regional and global climate through the surface-energy budget, as well as through the carbon cycle. The surface energy budget effects may be more important than the carbon-cycle effects. However, land-use impacts on climate cannot be adequately quanti­ ed with the usual metric of `global warming potential’. A new metric is needed to quantify the human disturbance of the Earth’s surface energy budget. This `regional climate change potential’ could offer a new metric for developing a more inclusive climate protocol. This concept would also implicitly provide a mechanism to monitor potential local-scale environmental changes that could infuence biodiversity.”

Marland, G., R.A. Pielke, Sr., M. Apps, R. Avissar, R.A. Betts, K.J. Davis, P.C. Frumhoff, S.T. Jackson, L. Joyce, P. Kauppi, J. Katzenberger, K.G. MacDicken, R. Neilson, J.O. Niles, D. dutta S. Niyogi, R.J. Norby, N. Pena, N. Sampson, and Y. Xue, 2003: The climatic impacts of land surface change and carbon management, and the implications for climate-change mitigation policy. Climate Policy, 3, 149-157

with the abstract

“Strategies to mitigate anthropogenic climate change recognize that carbon sequestration in the terrestrial biosphere can reduce the build-up of carbon dioxide in the Earth’s atmosphere. However, climate mitigation policies do not generally incorporate the effects of these changes in the land surface on the surface albedo, the fluxes of sensible and latent heat to the atmosphere, and the distribution of energy within the climate system. Changes in these components of the surface energy budget can affect the local, regional, and global climate. Given the goal of mitigating climate change, it is important to consider all of the effects of changes in terrestrial vegetation and to work toward a better understanding of the full climate system. Acknowledging the importance of land surface change as a component of climate change makes it more challenging to create a system of credits and debits wherein emission or sequestration of carbon in the biosphere is equated with emission of carbon from fossil fuels. Recognition of the complexity of human-caused changes in climate does not, however, weaken the importance of actions that would seek to minimize our disturbance of the Earth’s environmental system and that would reduce societal and ecological vulnerability to environmental change and variability.”

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

which includes the finding that

“Despite all these advantages, the traditional global mean TOA radiative forcing concept has some important limitations, which have come increasingly to light over the past decade. The concept is inadequate for some forcing agents, such as absorbing aerosols and land-use changes, that may have regional climate impacts much greater than would be predicted from TOA radiative forcing. Also, it diagnoses only one measure of climate change—global mean surface temperature response—while offering little information on regional climate change or precipitation. These limitations can be addressed by expanding the radiative forcing concept and through the introduction of additional forcing metrics. In particular, the concept needs to be extended to account for (1) the vertical structure of radiative forcing, (2) regional variability in radiative forcing, and (3) nonradiative forcing. A new metric to account for the vertical structure of radiative forcing is recommended below. Understanding of regional and nonradiative forcings is too premature to recommend specific metrics at this time. Instead, the committee identifies specific research needs to improve quantification and understanding of these forcings.”

In response to the Scientific American article, as my son has posted on in;

What Little Has Been Learned

“Almost a year has passed since the release of the East Anglia emails.  And despite all that has happened, there are some repeated indications that the climate science community just doesn’t get it.”

Reporters of climate science and a subset of climate scientists (who are often in leadership roles) continue to ignore and belittle those who disagree with them.

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Filed under Climate Science Misconceptions, Climate Science Reporting

Very Important New Paper “A Comparison Of Local And Aggregated Climate Model Outputs With Observed Data” By Anagnostopoulos Et Al 2010

There is a very important new paper which has compared climate model results with observations. It is

Anagnostopoulos, G. G., Koutsoyiannis, D., Christofides, A., Efstratiadis, A. & Mamassis, N. (2010) A comparison of local and aggregated climate model outputs with observed data. Hydrol. Sci. J. 55(7), 1094–1110.

The abstract reads

We compare the output of various climate models to temperature and precipitation observations at 55 points around the globe.We also spatially aggregate model output and observations over the contiguous USA using data from 70 stations, and we perform comparison at several temporal scales, including a climatic (30-year) scale. Besides confirming the findings of a previous assessment study that model projections at point scale are poor, results show that the spatially integrated projections are also poor.

The paper is examining the claim presented in the introduction of the paper that

According to the Intergovernmental Panel on Climate Change (IPCC), global circulation models (GCM) are able to “reproduce features of the past climates and climate changes” (Randall et al., 2007, p. 601).

What the authors of the Anagnostopoulos et al. (2010) paper have found is that [highlight added]

It is claimed that GCMs provide credible quantitative estimates of future climate change, particularly at continental scales and above. Examining the local performance of the models at 55 points, we found that local projections do not correlate well with observed measurements. Furthermore, we found that the correlation at a large spatial scale, i.e. the contiguous USA, is worse than at the local scale.

There is discussion of this paper in two accompanying articles.

The first paper is a comment on the Anagnostopoulos et al. (2010) paper. It is

 Wilby, R. L. (2010) Evaluating climate model outputs for hydrological applications – Opinion. Hydrol. Sci. J. 55(7), 1090–1093.

Wilby (2010) should be read also in its entirety, One excerpt, for example, reads

“Even if we could build perfect climate models, uncertainty about future economic and demographic pathways, natural forcings by solar and volcanic activity, and a host of non climatic pressures, mean that regional hydrological projections would still be highlyuncertain. In other words, characterizing uncertainty through concerted scientific action may be a tractable proposition, but there appears to be no immediate prospect of reducing uncertainty in the risk information supplied to decision makers.”

The second article is an editorial from the Editor of the journal

Kundzewicz, Z. W., and E.Z. Stakhiv (2010) Are climate models “ready for prime time” in water resources managementapplications, or is more research needed? Editorial. Hydrol. Sci. J. 55(7), 1085–1089.

In this article, in which they summarize the perspective of the Anagnostopoulos et al. (2010) and Wilby (2010) papers,  they include the excerpts from the text [highlight added]

Simply put, the current suite of climate models were not developed to provide the level of accuracy required for adaptation-type analysis. They were designed to provide a broad assessment of the response of the global climate system to greenhouse gas (GHG) forcings, and to serve as the basis for devising a set of GHG emissions policies to slow down the rate of growth of GHGs, and, by this, to mitigate global warming impacts. To expect more from these models is simply unrealistic at this time, as they do not even perform well as weather prediction models.

 However, it should be understood that RCMs (regional climate models) operate under a set of boundary conditions set by whatever GCM is being used. Hence, if the GCM does not do an adequate job of reproducing the climate signal of a particular region, the RCM will simply mimic those inaccuracies and biases, and propagate the uncertainties even further, albeit at a regional scale. It is not clear how the coupling of a RCM to a flawed GCM can provide more refined insights, any more than can statistical downscaling.

 An editor’s obligation is to publish papers that advance the state of science and of understanding that science. Hydrologists and water management professionals (hydrological and hydraulic engineers) have entered the scientific debate in force, because the GCMs are being advocated for purposes they were not designed for, i.e., watershed vulnerability assessments and infrastructure design. They are now examining whether these models are suitable, using their own perfectly legitimate and peer reviewed methods, as well as statistical tools developed over the course of a century of practical applications. They are not climate sceptics, but are sceptical of the claims of some climatologists and hydroclimatologists that these models are well suited for water management applications.

Our response to the question posed in the title of this editorial is that, while they are getting better, climate models are not (up to) ready for “prime time” yet, at least for direct application to water management problems.

These papers are open to discussion until April 2011. The Editor of the Hydrological Sciences Journal, Zbigniew Kundzewicz, is commended for his serving as a facilitator of all perspectives on the issues raised in the Anagnostopoulos et al. (2010) paper. If the  Anagnostopoulos et al conclusions are robust, it raises the question on the value of spending so much money on providing regional climate predictions decades into the future (e.g., see the 10/21/10 post entitled “The National Science Foundation Funds Multi-Decadal Climate Predictions Without An Ability To Verify Their Skill” .

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The National Science Foundation Funds Multi-Decadal Climate Predictions Without An Ability To Verify Their Skill

The University Corporation for Atmospheric Research [UCAR] has released a press statement titled

Climate change: Drought may threaten much of globe within decades [h/t to Marcel Crok]

The press release starts with the text [highlight added]

The United States and many other heavily populated countries face a growing threat of severe and prolonged drought in coming decades, according to a new study by National Center for Atmospheric Research (NCAR) scientist Aiguo Dai. The detailed analysis concludes that warming temperatures associated with climate change will likely create increasingly dry conditions across much of the globe in the next 30 years, possibly reaching a scale in some regions by the end of the century that has rarely, if ever, been observed in modern times.

Using an ensemble of 22 computer climate models and a comprehensive index of drought conditions, as well as analyses of previously published studies, the paper finds most of the Western Hemisphere, along with large parts of Eurasia, Africa, and Australia, may be at threat of extreme drought this century.

In contrast, higher-latitude regions from Alaska to Scandinavia are likely to become more moist.

Dai cautioned that the findings are based on the best current projections of greenhouse gas emissions. What actually happens in coming decades will depend on many factors, including actual future emissions of greenhouse gases as well as natural climate cycles such as El Niño.

The new findings appear this week as part of a longer review article in Wiley Interdisciplinary Reviews: Climate Change. The study was supported by the National Science Foundation, NCAR’s sponsor.

The press release is based on the paper

Aiguo Dai, 2010: Drought under global warming: a review. Wiley Interdisciplinary Reviews: Climate Change. DOI: 10.1002/wcc.81

with the abstract [highlight added]

“This article reviews recent literature on drought of the last millennium, followed by an update on global aridity changes from 1950 to 2008. Projected future aridity is presented based on recent studies and our analysis of model simulations. Dry periods lasting for years to decades have occurred many times during the last millennium over, for example, North America, West Africa, and East Asia. These droughts were likely triggered by anomalous tropical sea surface temperatures (SSTs), with La Niña-like SST anomalies leading to drought in North America, and El-Niño-like SSTs causing drought in East China. Over Africa, the southward shift of the warmest SSTs in the Atlantic and warming in the Indian Ocean are responsible for the recent Sahel droughts. Local feedbacks may enhance and prolong drought. Global aridity has increased substantially since the 1970s due to recent drying over Africa, southern Europe, East and South Asia, and eastern Australia. Although El Niño-Southern Oscillation (ENSO), tropical Atlantic SSTs, and Asian monsoons have played a large role in the recent drying, recent warming has increased atmospheric moisture demand and likely altered atmospheric circulation patterns, both contributing to the drying. Climate models project increased aridity in the 21st century over most of Africa, southern Europe and the Middle East, most of the Americas, Australia, and Southeast Asia. Regions like the United States have avoided prolonged droughts during the last 50 years due to natural climate variations, but might see persistent droughts in the next 20–50 years. Future efforts to predict drought will depend on models’ ability to predict tropical SSTs.”

This UCAR press release and the article itself are not scientifically robust. Buried within this material are the significant cavaets:

1.  “Dai cautioned that the findings are based on the best current projections of greenhouse gas emissions. What actually happens in coming decades will depend on many factors, including actual future emissions of greenhouse gases as well as natural climate cycles such as El Niño.”

2. “Future efforts to predict drought will depend on models’ ability to predict tropical SSTs.”

In other words, there is NO way to assess the skill of these models are predicting drought as they have not yet shown any skill in SST predictions on time scales longer than a season, nor natural climate cycles such as El Niño [or the PDO, the NAO, ect].

Funding of multi-decadal regional climate predictions by the National Science Foundation which cannot be verified in terms of accuracy is not only a poor use of tax payer funds, but is misleading policymakers and others on the actual skill that exists in predicting changes in the frequency of drought in the future.

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New Paper “More Than CO2: A Broader Picture For Managing Climate Change And Variability To Avoid Ecosystem Collapse” By McAlpine Et Al 2010

We have a new paper, prepared under the leadership of Clive McAlpine of the University of Queensland, that has been accepted. It is

McAlpine, C.A., W.F. Laurance, J.G. Ryan, L. Seabrook, J.I. Syktus, A.E. Etter, P.M. Fearnside, P. Dargusch, and R.A. Pielke Sr. 2010: More than CO2: A broader picture for managing climate change and variability to avoid ecosystem collapse. Current Opinion in Environmental Sustainability, in press.

The abstract reads

“Climate change policies currently focus on reducing the concentration of atmospheric greenhouse gases, but pay limited attention to feedbacks between the land surface and the climate system. Forests and woodlands play an important role in the climate system by buffering climate extremes, maintaining the hydrological cycle and sequestering carbon. To reduce the potential impact of climate variability and change on society and the environment, therefore, requires a broader focus of environmental sustainability and resilience that is underpinned by the restoration of feedbacks between vegetation and climate. We urge a stronger integration of land use and climate change policies, a virtual halt to all deforestation, and an acceleration of investment in strategic reforestation, especially in tropical and sub-tropical regions, supported by a comprehensive global forest monitoring program. Without these actions, the degradation of the Earth’s ecosystems will continue exacerbated by, and exacerbating, variability and changes in temperature, precipitation and extreme weather events.”

The conclusion reads

“The role of terrestrial ecosystems, especially forests and woodlands, in the climate debate has predominantly focused on their potential for carbon sequestration. We argue it is critical to adopt a broader perspective of the role of forests and other ecosystems in the climate debate, policies and actions. This requires global and regional climate policies which recognise the climate regulation function that forests and woodlands play through moderating regional climate variability, resisting abrupt change to existing climate regimes, as well as underpinning the hydrological cycle. This is especially important in the tropics and subtropics. Failure to acknowledge and adopt this broader perspective on dealing with the problem of climate change will result in sub-optimal solutions at the global scale and possible severe and irreversible damage at the regional scale.”

This is yet another paper that documents why we need a broader focus on the role of humans in the climate system than just the effects due to the radiative effect of added CO2.

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Filed under Climate Change Forcings & Feedbacks