Monthly Archives: March 2008

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

There continues to be misunderstandings on my viewpoint on the role of humans within the climate system. This weblog is written to make sure it is clear, and can be used whenever someone asks the question as to where does Pielke Sr. stand on this issue.

 As I have written in the Main Conclusions of Climate Science

“Humans are significantly altering the global climate, but in a variety of diverse ways beyond the radiative effect of carbon dioxide. The IPCC assessments have been too conservative in recognizing the importance of these human climate forcings as they alter regional and global climate.”

and that

“Attempts to significantly influence regional and local-scale climate based on controlling CO2 emissions alone is an inadequate policy for this purpose.”

These conclusions are different from those who claim that the global average radiative effect of carbon dioxide is by far the major human climate forcing, as well as from those who conclude that natural climate variations dominate climate change and that the human climate forcings are inconsequential.

My viewpoint is also well articulated in

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

and you are encouraged to read the Executive Summary of that report [a report which whas been ignored by the media despite its broad base of authorship and its extensive review before it was published].

The reason that those who focus on the global average radiative forcing of carbon dioxide are missing the bulk of human climate forcings include the following:

1. Atmosphere and ocean circulations respond to regional forcings not a global average (e.g., see and see)

2. The other human climate forcings include

  • the diverse influence of human-caused aerosols on regional (and global)  radiative heating (e.g., see).
  • the effect of aerosols on cloud and precipitation processes (e.g., see)
  • the influence of aerosol deposition on climate (e.g., see and see)
  • the effect of land cover/land use on climate (e.g., see and  see)
  • the biogeochemical effect of added atmosopheric CO2 has a greater effect on the climate system than the radiative effect of added CO2 (e.g. see).

Natural climate variations and change, have also been underestimated (and are only poorly understood) based on examination of the historical and paleo-climate record (e.g., see and see).

Human climate forcings have a more significant role in altering the weather than does a global average increase in the radiative effect of an increase in the atmospheric concentration of CO2.  This does not mean that we should not work to limit the increase of this gas in the atmosphere, but it is not the dominant climate forcing that affects society and the environment.

Policies that focus on CO2 by itself are ignoring definitive research results (such as reported in the 2005 National Research Council report) that humans have a much broader influence on the climate system than was communicated in the 2007 IPCC report.  To neglect these other climate forcings represents a failure by policymakers (and the media) to utilize this scientifically robust information.

The neglect of including the diversity of human climate forcings indicates that the real objective of those promoting the radiative effect of the addition of atmospheric CO2 as the dominant human climate forcing is to promote energy and lifestyle changes. Their actual goal is not to develop effective climate policies. 

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Filed under Climate Science Misconceptions, Climate Science Reporting, RA Pielke Sr. Position Statements

A Short Tutorial On Global Warming

 Climate Science (and other weblogs) have posted detailed information on the issues associated with different methods to assess global climate system heat changes. Readers can access examples of these posts on Climate Audit, Watts Up With That, Hall of Record, ICECAP and The Blackboard.

 This current Climate Science weblog is intended to just summarize the issue as there are still individuals who perpeturate the claim that measuring near surface air temperature at irregularly spaced observation sites around the globe can accurately diagnose global warming.

As repeatedly emphasized on Climate Science, the use of surface air temperature is not a measure of climate system heat since it has almost no mass associated with it. Heat of the climate system requires that temperature change (and heat associated with the phase of water) ocurr over mass.  The relation of a change in global climate system heat change is dominated by ocean heat changes, as succincty summarized in Table 1 of

Levitus, S., J.I. Antonov, J. Wang, T.L. Delworth, K.W. Dixon, and A.J. Broccoli, 2001: Anthropogenic warming of Earth’s climate system. Science, 292, 267-269

where they write

“Our analysis of components of Earth’s heat balance quantitatively demonstrates that during the latter half of the 20th century, changes in ocean heat content dominate the changes in Earth’s heat balance.”

This heat change can be expressed as

ΔH = CΔT * Mass of the ocean where C is the specific heat capacity of sea water in units of Joules per degree per kilogram, T is temperature and M is the mass of the ocean in kilograms.

 Thus if  ΔH > 0, there is global warming.

No where is there a need to use a global average surface temperature trend to diagnose global warming, and, in fact, its use is misleading since there is an inconsequential amount of mass of the climate system involved.  Over the oceans, the sea surface temperatures are correlated with the upper ocean heat content, but over land there are a variety of serious problems with its use as reported in the paper

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

Climate Science (and others; e.g. see) have been reporting on the shortcomings of the use of the global average surface average temperature trend to diagnose global warming, but this poor metric continues to be used by those advocating for particular policy actions on climate (e.g. see its inadequate and incomplete explanation in Wikipedia).

However, using the actual robust metric of global warming, ΔH, there has been none since 2004 (e.g. see), at least in the upper 700m of the ocean.

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Reality Check On Antarctic Sea Ice

The news reports on the breaking off of a portion of floating ice in Antarctica have received wide distribution (i.e. do a google search under news for Antarctic sea ice and hundreds of reports appear on this event). These news reports claim that this breaking is due to global warming. As just one example of the statements in the news, The Guardian wrote 

 “The collapsing shelf suggests that climate change could be forcing change much more quickly than scientists had predicted.

“The ice shelf is hanging by a thread,” said Professor David Vaughan of the British Antarctic Survey (BAS). “We’ll know in the next few days or weeks what its fate will be.”

The Wilkins shelf covers an area of 5,600 square miles (14,500 sq km). It is now protected by just a thin thread of ice between two islands.

Vaughan was a member of the team that predicted in 1993 that global warming could cause the Wilkins shelf to collapse within 30 years.”

This media reporting has become typical of the bias that many journalists have. Not reported in the media (but well reported on ICECAP by Joe D’Aleo)  the media has ignored in their reporting the increase in Antarctic sea ice cover in recent years, with, at present, a coverage that is well over 1 million square kilometers above average (see)!

In fact, over the globe, since the Arctic sea ice cover is not far below its average and the Antarctic sea ice coverage is well above average for this time of the year, the global coverage of sea ice is actually above average after being below last year (see). There is no way to know if this is just a short term perturbation, but at the very least the news media should have been honest and balanced in their coverage.

Unfortunately, it appears that most journalists just parrot the perspective of the first news release on these climate issues, without doing any further investigation. If this is inadvertent, they need to be educated in climate science. If deliberate bias, they are clearly advocates and the reporters should be clearly and publically identified as having such a bias. In either case, the public is being misinformed!

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Filed under Climate Science Misconceptions, Climate Science Reporting

Interesting Weblog On Hall Of Record Entitled “What is Normal”

There is an informative post on the website Hall of Record entitled “What is Normal”.  I recommend Climate Science readers read the contributions on that weblog on this subject.

With respect to the term “normal, there is an issue as to what it means in climate science.  In climate, “normal” is actually used to mean “average”, but it is misleading since a temperature that is above average is not abnormal unless it exceeds a threshold of deviation.

 We discuss this issue in our paper

 Pielke, R.A. and N. Waage, 1987: A definition of normal weather. Natl. Wea. Dig., 12, 20-22.

The abstract reads

“This paper clarifies the distinction between abnormal weather, and above and below average weather, using standard statistical analyses. Abnormal maximum and minimum temperatures are defined as requiring at least two standard deviations from the mean; otherwise even though they could be above or below average, the weather is still “normal”.  July and January maximum and minimum temperatures for Denver, New York, Los Angeles, Miami and Bismarck are presented as examples of this analysis.”

Thus when the media or weather broadcasters state that the maximum (or minimum)  temperature for a particular day is “above normal”, unless it is a large (e.g.  greater than 2 sigma) deviation from the average maximum (or minimum) temperature, it is not really above normal. 

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Meeting Announcement: AAWE Workshop in Vail August 20-22 2008

There will be a Workshop of the American Association of Wind Engineers on August 20-22 2008 in Vail Colorado. The meeting information can be found at AAWE Conferences. This is a world class organization and those who are working on this topc or otherwise interested in attending will find much of value. This organization is an essential player in the development of wind as an alternate energy source.

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Follow Up On News Article “Global Warming Rushes Timing Of Spring”

Richard Berler of the Laredo Morning Times has a very good follow up to the post on Climate Science in the post Comments On The News Article by Seth Borenstein entitled “Global Warming Rushes Timing of Spring”.  His article is titled “Global warming not always at fault” and can be found towards the bottom of the page. It is worth reading.

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A Proposed Test Suite for Atmospheric Model Dynamical Cores

There is an excellent proposal entitled  A Proposed Test Suite for Atmospheric Model Dynamical Cores by Christaine Jablonowski of the University of Michigan which Climate Science was alerted to from a February 3 2008 weblog on Climate Audit.

The idea for this test is described as

   “Tests of atmospheric General Circulation Models (GCMs) and, in particular, tests of their dynamical cores are important steps towards future model improvements. They reveal the influence of an individual model design on climate and weather simulations and indicate whether the circulation is described representatively by the numerical approach.
      Testing a global 3D atmospheric model is not straightforward. In the absence of non-trivial analytic solutions, the model evaluations most commonly rely on intuition, experience and model intercomparisons. In addition, GCM simulation statistics are typically compared to global reanalysis data while numerical weather forecasts are compared to local observations. Such approaches are not applicable to pure dynamical core assessments that isolate the dynamics package from the physical parameterizations. In general, three different sets of equations are most commonly used in dynamical cores. These include the hydrostatic primitive equations as well as the non-hydrostatic shallow-atmosphere and non-hydrostatic deep-atmosphere equation sets. As modeling groups now move towards the next generation of dynamical cores a standard test suite for hydrostatic and non-hydrostatic dynamics packages on the sphere if highly desirable. This webpage contributes to this effort. It suggests a collection of dynamical core test cases with varying complexity.”

Such evaluations of the global models used to make multi-decadal climate predictions are long overdue. In the paper

Pielke, R.A., 1991: Overlooked scientific issues in assessing hypothesized greenhouse gas warming. Environ. Software, 6, 100-107, I wrote

“The horizontal grid spacing of general circulation models is around 400 km. As shown by Pielke [the first edition of Pielke, 2002], as least four grid increments are required to reasonably represent an atmospheric feature, thus this grid resolution would only permit features 1600 km or larger to be reasonably represented in the models, Since extratropical cyclones often are observed to have horizontal wavelengths as small as 500 km or so, they are poorly represented in these models, Since these features provide the major physical mechanism for the exchange of heat, moisture, and momentum between the subtropics and the polar regions, the inability of GCM representations to adequately represent these exchanges is a serious shortcoming. Tropical cyclones, which also provide an important mechanism for exchanges between the tropics and higher latitude is even more poorly represented since its scales of important physical processes includes the eye wall which can be tens of kilometers in radial size.”

and

“Upwelling of deep, cold ocean waters occurs at a number of locations around the world including the equatorial Pacific, around Antarctica, and off the west coast of North America, northern South America, northwest Africa, southwest Africa, and elsewhere. Caused by the direction and speed of the wind at the ocean surface, these upwelled regions of cold surface waters usually have an extent in one spatial direction of 50km or so. Since atmosphere-ocean GCMs have spatial resolutions on the order of 400km, these important sinks for carbon dioxide are ignored.”

The test of the dynamical core fits into these evaluations and assessment of the global climate models as prediction tools. As a necessary condition, when configured to run in a multi-decadal predictive mode they should still be used to make short-term global weather predictions in order to asses their skill at simulating the development and movement of major high and low pressure systems, including tropical cyclones. Moreover, they should be run as seasonal weather predictions using inserted sea surface temperatures at the initial time in order to see if they can skillfully predict the development of El Nino and La Nina events, as well as other circulation patterns such as the North Atlantic Oscillation. If they cannot accurately predict these short term and seasonal weather patterns, they should not believed as valid and societally useful prediction tools on the regional (and even the global average) scale decades into the future.

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New Paper Elevates The Role Of Black Carbon In Global Warming

Climate Science has repeatedly reported that the attribution of the radiative effect of CO2 to global warming is significantly overstated; e.g. see

What Fraction of Global Warming is Due to the Radiative Forcing of Increased Atmospheric Concentrations of CO2?

and my powerpoint talk

Pielke, R.A. Sr., 2006: Regional and Global Climate Forcings. Presented at the Conference on the Earth’s Radiative Energy Budget Related to SORCE, San Juan Islands, Washington, September 20-22, 2006.

 Now there is a new paper by V. Ramanathan and Greg Carmichael to appear on March 23 in Nature Geoscience titled “Global and regional climate changes due to black carbon” [and thanks to Jos de Laat for alerting us to it!].

 The Scripps news  release which announces this is titled “Black Carbon Polluition Emerges as Major Player in Global Warming”.

The report writes that

“…. soot and other forms of black carbon could have as much as 60 percent of the current global warming effect of carbon dioxide, more than that of any greenhouse gas besides CO2″

“In the paper, Ramanathan and Carmichael integrated observed data from satellites, aircraft and surface instruments about the warming effect of black carbon and found that its forcing, or warming effect in the atmosphere, is about 0.9 watts per meter squared. That compares to estimates of between 0.2 watts per meter squared and 0.4 watts per meter squared that were agreed upon as a consensus estimate in a report released last year by the Intergovernmental Panel on Climate Change (IPCC), a U.N.-sponsored agency that periodically synthesizes the body of climate change research. “

and

“Ramanathan and Carmichael said the conservative estimates are based on widely used computer model simulations that do not take into account the amplification of black carbon’s warming effect when mixed with other aerosols such as sulfates. The models also do not adequately represent the full range of altitudes at which the warming effect occurs. The most recent observations, in contrast, have found significant black carbon warming effects at altitudes in the range of 2 kilometers (6,500 feet), levels at which black carbon particles absorb not only sunlight but also solar energy reflected by clouds at lower altitudes.”

 Ramanthan is quoted as saying

 “‘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.'”

Climate Science (and the 2005 National Research Council report Radiative forcing of climate change: Expanding the concept and addressing uncertainties) have urged that the policy community move beyond their myopic view of global warming and this study will hopefully encourage them them to broaden their view.

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From Model Based Parameterizations to Lookup Tables: An EOF Approach by Leoncini, Pielke Sr. and Gabriel

We have a new research paper that demonstrates an important new way to implement parameterizations within weather and climate models. This paper also illustrates that parameterizations need not be basic physic-based approaches to be as useful when applied to represent the aggregate effect of physical processes. The paper is

 Leoncini, G., R.A. Pielke Sr., and P. Gabriel, 2008: From model based parameterizations to Lookup Tables: An EOF approach. Wea. Forecasting, DOI: 10.1175/2008WAF2007033.1, in press.

Abstract
The goal of this study is to transform the Harrington radiation parameterization into a transfer scheme or lookup table, which provides essentially the same output (heating rate profile and short and longwave fluxes at the surface) at a fraction of the computational cost. The methodology put forth here does not introduce a new parameterization simply derived from the Harrington scheme, but shows that given a generic parameterization it is possible to build an algorithm, largely not based on the physics, that mimics the outcome of the parent parameterization. The core concept is to compute the Empirical Orthogonal Functions of all the input variables of the parent scheme, run the scheme on the EOFs, and express the output of a generic input sounding exploiting the input-output pairs associated to the EOFs. The weights are based on the difference between the input and EOFs water vapor mixing ratios. A detailed overview of the algorithm and the development of a few transfer schemes are also presented. Results show very good agreement (r > 0.91) between the different transfer schemes and the Harrington radiation parameterization with a very significant reduction in computational cost (at least 95%).

Conclusions
In this study a methodology to develop a LUT [Look-Up-Table] or TS [Transfer Scheme] from a parameterization has been presented. It is important to further clarify that this work does not introduce a new parameterization simply derived from a preexisting one, but reduces a parameterization to a TS, whose core concept is to compute the EOFs of the parent scheme input variables, under clear sky conditions, and run it on the EOFs. Then the TS output of a generic input is a weighted average of the EOFs output, where the weights are based on a form of distance between the input and each individual EOF. Several TS have been develop for the Harrington radiation scheme under clear sky conditions, by using different EOFs and their errors have been thoroughly analyzed, as well as their computational speed. The errors with respect to the parent parameterization, at times can be larger than what is commonly accepted as error for a radiation parameterization compared against a line-by-line code, but this kind of analysis has not been published for the HS, as well as for other mesoscale schemes, at least for the clear sky case. Therefore it is not possible to know with certainty the error introduced with the TS and it is suggested that a different weighting strategy is very likely to improve the shortwave flux errors. Furthermore once the best TS has been implemented into RAMS the meteorological fields after a two-day simulation show a good agreement with the parent scheme and a comparison against the meteorological fields obtained by use of the Chen-Cotton scheme indicates that the uncertainties introduced by the TS, as compared with the HS are less significant than the ones due to the second scheme. Finally the calculations necessary for the TS are carried out at a fraction of the original cost.

While this study is limited to the Harrington radiation parameterization, it is reasonable to believe that the same methodology can be extended to a cloudy sky and applied to other parameterizations with similar results as first envisioned in Pielke et al. (2006).

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Recognition Of The Importance of Landscape Change

There is effective media recognition of the importance of landscape change on weather and climate. It is in a news article on March 15 2008 by Jim Konkoly in Highlands Today titled “Drained Wetlands Having Dramatic Effect On Our Area”. It reads

“Every day, the Archbold Biological Station’s weather station is providing data to help the federal National Climatic Data Center determine if, as weather data strongly suggests, south central Florida’s climate is getting hotter and drier during the summers while the winters have more deep freezes which are lasting longer and getting colder.

A recent study, which will be followed up by more research, suggests that the draining of the south central Florida wetlands may be responsible for the climate changes, which have huge implications on the water supply for agriculture and population growth and could threaten the citrus industry.

Carbon dioxide and other greenhouse gases may not be the biggest problem causing climate change that threatens local economies, the study suggests.

Right here in south central Florida, the draining of wetlands may have a bigger impact, according to the 2004 study by Roger Pielke, one of his students, Curtis Marshall, and their colleagues Louis Steyaert and Debra Willard.

Their report, “Deep Freeze and Sea Breeze, Changing Land and Weather in Florida,” can be read online at NASA’s Earth Observatory link.

NASA’s introduction to their report states:

“Combining their diverse expertise in climatology, environmental modeling, ecology, geography, geology and remote sensing, the team ended up with an explanation for how land-cover change in central and southern Florida could simultaneously be responsible for hotter, drier summers and wintertime deep freezes that are longer lasting and more severe.”

NASA’s introduction to the study also says:

“Three decades of research have brought Pielke to the conclusion that when it comes to the kinds of climate change people experience where they live, land-surface changes like deforestation, urbanization, and the draining of wetlands are at least as important – and maybe more important – than increasing atmospheric greenhouse gases.”

Pielke’s report begins by saying the drainage canals, dams, dikes and reservoirs built throughout south central Florida converted a huge area that was completely covered with various types of wetlands into today’s landscape with “dramatically reduced” water flow and wetlands.

Hilary Swain, executive director of Archbold, said while the Pielke research report is scientific, it can be read and understood by lay people.

To see the entire report, as well as the charts and maps, go to:

www.earthobservatory.nasa.gov/Study/DeepFreeze/dee…

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