Monthly Archives: September 2009

Scientificially Absurd News Headline, Which, Unfortunately Prevades The Current Debate on Climate and Energy Policy

The news today includes an article by Richard Cowan of Reuters titled  “US climate control debate heats up in Senate” . The article itself is informative.

However, the  claim in the header of the article that the government can design a program for “climate control” is absurd.

In our book,

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

Bill Cotton and I presented the history of how weather modification was oversold to policymakers and funding agencies. With the claims that the governement is going to control climate, the excesses that occured with respect to weather modification are being taken to an even higher level.

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Filed under Bias In News Media Reports, Climate Science Misconceptions

New Paper Accepted “Urbanization Signature In The Observed Heavy Rainfall Climatology Over India” By Kishtawal Et Al 2009

We have a new paper accepted for publication which documents the important role of urbanization on precipitation. It is

Kishtawal C., D. Niyogi, M. Tewari, R. A. Pielke Sr., and M. Shepherd, 2009, Urbanization Signature in the Observed Heavy Rainfall Climatology over India, International Journal of Climatology, accepted September 2009.

The abstract reads

“Using a long-term daily rainfall dataset and high resolution gridded analysis of human population, this study showed a significantly increasing trend in the frequency of heavy rainfall climatology over urban regions of India during the monsoon season. Urban regions experience less occurrences of light rainfall and significantly higher occurrences of intense precipitation compared to non-urban regions. Very heavy and extreme rainfall events showed increased trends over both urban and rural areas, but the trends over urban areas were larger and statistically more significant.”

Our analysis suggests that there is adequate statistical basis to conclude that the observed increasing trend in the frequency of heavy rainfall events over Indian monsoon region is more likely to be over regions where the pace of urbanization is faster. Moreover, rainfall measurements from satellites also indicate that urban areas are more (less) likely to experience heavier (lighter) precipitation rates compared to non-urban areas. While the mechanisms causing this enhancement in rainfall remain to be studied, the results provide the evidence that the increase in the heavy rainfall climatology over Indian monsoon region is a signature of urban induced rainfall anomaly.”

The conclusion reads

“In the present study, we have tried to establish a link between the trends of urbanization as detected by the remote sensing data and the patterns of precipitation over the Indian summer monsoon region. Our analysis suggests that there is adequate statistical basis to conclude that the observed increasing trend in the frequency of heavy rainfall events over the Indian monsoon region is more likely to be over the regions where the pace of land use/land cover change through urbanization is faster. Moreover, rainfall measurements from satellites also indicate that urban areas are more (less) likely to experience heavier (lighter) precipitation rates compared to non-urban areas. How exactly the UHI and the concentration of different species of urban aerosols impact the cloud microphysics in a humid and convectively unstable environment of monsoon, is still an active area of research.”

This study illustrates yet again why a focus on the emissions of CO2 and other greenhouse gases as the dominate human climate forcing is not an accurate characterization of the real world climate system.

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Further Support for Klotzbach et al. 2009 – Observational Evidence of a Change of Surface Radiative Forcing in a Paper: Philipona et al. 2004

Urs Neu has alerted us to an observationally-based paper that documents a change of surface radiative forcing  that is consistent with our studies (as well as further refutes claims to the contrary; e.g., see).

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

and

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., in press (with edits still to be made in the final published version).

In the second paper we wrote

“…… if, for instance, there is a long-term positive trend in greenhouse gas concentrations or cloudiness over the observing site, it may introduce an upward bias in the observational record of minimum temperatures that necessarily will result in an upward bias in the long-term surface temperature record.”

The paper recommended by Urs Neu is

Philipona, R., B. Durr, C. Marty, A. Ohmura, and M. Wild (2004), Radiative forcing – measured at Earth’s surface – corroborate the increasing greenhouse effect, Geophys. Res. Lett., 31, L03202, doi:10.1029/ 2003GL018765.

The abstract reads

“The Intergovernmental Panel of Climate Change (IPCC) confirmed concentrations of atmospheric greenhouse gases and radiative forcing to increase as a result of human activities. Nevertheless, changes in radiative forcing related to increasing greenhouse gas concentrations could not be experimentally detected at Earth’s surface so far. Here we show that atmospheric longwave downward radiation significantly increased (+5.2(2.2) Watts per meter squared) partly due to increased cloud amount (+1.0(2.8) Watts per meter squared) over eight years of measurements at eight radiation stations distributed over the central Alps. Model calculations show the cloud-free longwave flux increase (+4.2(1.9) Watts per meter squared) to be in due proportion with temperature (+0.82(0.41) C) and absolute humidity (+0.21(0.10) g per meter cubed) increases, but three times larger than expected from anthropogenic greenhouse gases. However, after subtracting for two thirds of temperature and humidity rises, the increase of cloud-free longwave downward radiation (+1.8(0.8) Watts per meter squared) remains statistically significant and demonstrates radiative forcing due to an enhanced greenhouse effect.”

This paper documents that changes of 1 Watt per meter squared (or more) in the longwave fluxes  that we examined in Pielke and Matsui (2005) are realistic. The Klotzbach et al. (2009) paper demonstrates that a significant bias is introduced in the land portion of the global surface temperature trend which is used in the assessment of global warming, that can be explained, at least in part,  due to such changes in longwave radiative fluxes at night.

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The IPCC Claim Regarding A Linear Relationship Between The Global Average Surface Temperature Trends And Global Average Radiative Forcing Is Quantitatively Inaccurate

In our paper

 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., in press [with edits still to be made in the final published version; see],

we show that the surface and lower tropospheric temperature trends are diverging in time. We offer an explantion for some of this related to the use of minimum temperatures over land as part of the construction of the global average surface temperature trend. Other sources of bias and uncertainty are reported in our 2007 JGR paper [Pielke et al 2007: Unresolved issues with the assessment of multi-decadal global land surface temperature trends].

This also means that the diagnosis of the radiative forcing using the surface temperature trends introduces errors. The assumption of a linear relationship between the radiatve forcings and surface temperature is clearly stated in the 2007 IPCC WG1 report (e.g. see Chapter 2 page 133), where it is written

“Radiative forcing [RF] can be related through a linear relationship to the global mean equilibrium temperature change at the surface (delta Ts): delta Ts = lambda * RF, where lambda is the climate sensitivity parameter (e.g.,Ramaswamy et al., 2001).”

The lower troposphere is also expected to have a linear relationship to the radiative forcing although amplified relative to the surface; e.g. see Figure 5.6 for the tropics in CCSP 1.1. Chapter 5.

Our Klotzbach et al. 2009 paper shows that there is not a temporally invariant linear relationship between the global average surface and lower tropospheric temperature trends.  Based on this paper, and our other papers such as JGR 2007, there is also not a linear relationship between the global average surface temperature trends and the radiative forcing. This view is at significant variance to the IPCC view, which used the CCSP 1.1 report in its assessment. In our new Klotzbach et al paper, we present additional observational evidence that the paragraph above from the IPCC report is not correct, and we discuss one of the reasons for the discrepancy.

The 2005 NRC report supports our view where it is written

“The simplification of complex, mechanistically disparate processes to the same radiative forcing metric, with the implication that positive forcings may cancel negative forcings, provides a way of easily communicating climate forcing factors and their relative importance to general audiences. However, a net zero global mean radiative forcing may be associated with large regional or nonradiative (e.g., precipitation) changes. Further, when forcings are added, uncertainties in individual forcings must be propagated, resulting in large uncertainties in the total forcing. Adding forcings also belies the complexity of the underlying chemistry, physics, and biology. It suggests that all effects on climate can be quantified by a similar metric without knowing, or needing to know, the details of the climate response as captured in feedback effects. Yet there are many aspects of climate change—including rainfall, biodiversity, and sea level—that are currently not related quantitatively, much less linearly, to radiative forcings.”

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Our Paper “Impact Of Land Surface Heterogeneity On Mesoscale Atmospheric Dispersion” By Wu Et Al 2009 Has Been Published

Our new paper

Yuling Wu, Udaysankar S. Nair , Roger A. Pielke Sr., Richard T. McNider, Sundar A. Christopher and Valentine G. Anantharaj, 2009: Impact of Land Surface Heterogeneity on Mesoscale Atmospheric Dispersion. Boundary-Layer Meteorology. 10.1007/s10546-009-9415-1,

has appeared in print [this was first weblogged on in August; see]

The abstract reads

“Prior numerical modelling studies show that atmospheric dispersion is sensitive to surface heterogeneities, but past studies do not consider the impact of a realistic distribution of surface heterogeneities on mesoscale atmospheric dispersion. While these focussed on dispersion in the convective boundary layer, the present work also considers dispersion in the nocturnal boundary layer and above. Using a Lagrangian particle dispersion model (LPDM) coupled to the Eulerian Regional Atmospheric Modeling System (RAMS), the impact of topographic, vegetation, and soil moisture heterogeneities on daytime and nighttime atmospheric dispersion is examined. In addition, the sensitivity to the use of Moderate Resolution Imaging Spectroradiometer (MODIS)-derived spatial distributions of vegetation characteristics on atmospheric dispersion is also studied. The impact of vegetation and terrain heterogeneities on atmospheric dispersion is strongly modulated by soil moisture, with the nature of dispersion switching from non-Gaussian to near-Gaussian behaviour for wetter soils (fraction of saturation soil moisture content exceeding 40%). For drier soil moisture conditions, vegetation heterogeneity produces differential heating and the formation of mesoscale circulation patterns that are primarily responsible for non-Gaussian dispersion patterns. Nighttime dispersion is very sensitive to topographic, vegetation, soil moisture, and soil type heterogeneity and is distinctly non-Gaussian for heterogeneous land-surface conditions. Sensitivity studies show that soil type and vegetation heterogeneities have the most dramatic impact on atmospheric dispersion. To provide more skilful dispersion calculations, we recommend the utilisation of satellite-derived vegetation characteristics coupled with data assimilation techniques that constrain soil-vegetation-atmosphere transfer (SVAT) models to generate realistic spatial distributions of surface energy fluxes.”

In terms of climate, this paper is another example of the major role of landscape heterogeneity in local and regional climate patterns.

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Comment Submitted To Bulletin Of The American Meteorological Society

I have submitted a formal Comment to the Bulletin of the American Meteorological Society (BAMS), which I originally commented on in my weblog on August 6 2009 (see).

Pielke Sr., R.A., 2009: Comment on “James Hurrell, Gerald A. Meehl, David Bader, Thomas L. Delworth, Ben Kirtman, and Bruce Wielicki, 2009: A Unified Modeling Approach to Climate System Prediction. Bull. Amer. Meteor. Soc., in press”, Bull. Amer. Meteor. Soc., submitted.

I will post the Reply when available.

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Comment On Andy Revkin’s August 3 2009 article “Nobel Halo Fades Fast for Climate Change Panel”

There was an interesting article on August 3 2009 by Andy Revkin [thanks to Benny Peiser for alerting us to this] titled  “Nobel Halo Fades Fast for Climate Change Panel”.  This article includes the following text:

 “…… scientists who question the likelihood of a calamitous disruption of the Earth’s climate accuse the panel of cherry-picking studies and playing down levels of uncertainty about the severity of global warming.

‘It just feels like the I.P.C.C. has gone from being a broker of science to a gatekeeper,’ said John R. Christy, a climate scientist at the University of Alabama, Huntsville, and a former panel author.

In an interview, Rajendra K. Pachauri, chairman of the I.P.C.C., rejected the charge of bias, noting layers of transparent peer review. “

John Christy is completely correct on his view of the IPCC as a gatekeeper. The IPCC WG1 report is a biased advocacy document.  I have documented the gatekeeper format of  the WG1 2007 IPCC report in my Appendix 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.

There was a useful proposal in the Revkin news article that should be pursued. In the article, it states

“……..Dr. Nicholls, a climate scientist at Monash University in Victoria, Australia [proposed] that the group [in his proposal this would be the IPCC scientists] write more focused, expeditious reports on issues relevant to setting policy. Dr. Nicholls suggested that the panel could eventually shift to reviewing the flow of research on more basic questions through a constantly updated Wikipedia-style system.”

This is an good idea, but the ability to update a Wikipedia-style system must be available to all climate scientists,  not just a cherrypicked subset of this community.

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New Paper “Albedo Effect On Radiative Errors In Air Temperature Measurements” By Huwald Et Al 2009

There is a new paper which addresses the issue of surface albedo and how this affects surface air temperatures (thanks to Dev Niyogi for alerting us to it!). The article is

 Huwald, H., C. W. Higgins, M.-O. Boldi, E. Bou-Zeid, M. Lehning, and M. B. Parlange (2009): Albedo effect on radiative errors in air temperature measurements, Water Resour. Res., 45, W08431, doi:10.1029/2008WR007600.

The abstact reads 

“Most standard air temperature measurements are subject to significant errors mainly due to sensor heating by solar radiation, even when the measurement principle is accurate and precise. We present various air temperature measurements together with other measurements of meteorological parameters using different sensor systems at a snow-covered and a vegetated site. Measurements from naturally ventilated air temperature sensors in multiplate shields are compared to temperatures measured using sonic anemometers which are unaffected by solar radiation. Over snow, 30 min mean temperature differences can be as large as 10°C. Unshielded thermocouples were also tested and are generally less affected by shortwave radiation. Temperature errors decrease with decreasing solar radiation and increasing wind speed but do not completely disappear at a given solar radiation even in the presence of effective ventilation. We show that temperature errors grow faster for reflected than for incident solar radiation, demonstrating the influence of the surface properties on radiative errors, and we detect the albedo as a variable with major influence on the magnitude of the error as well as a key quantity in possible error correction schemes. An extension is proposed for an existing similarity regression model to correct for radiative errors; thus, surface-reflected shortwave radiation is identified as a principal source of error and the key variable for obtaining a unique nondimensional scaling of radiative errors.”

This paper further documents one of the  sources of spatially non-representative temperature data that we highlighted in our papers

Pielke Sr., R.A. J. Nielsen-Gammon, C. Davey, J. Angel, O. Bliss, N. Doesken, M. Cai., S.  Fall, D. Niyogi, K. Gallo, R. Hale, K.G. Hubbard, X. Lin, H. Li, and S. Raman, 2007: Documentation of uncertainties and biases associated with surface temperature measurement sites for climate change assessment. Bull. Amer. Meteor. Soc., 88:6, 913-928.

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.

The Huwald et al 2009 paper shows that if the local surface characteristics, such as albedo, change over time, the long term trends in surface temperatures will have a non-spatially representative component if the larger scale landscape did not have the same changes.

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The Vulnerability Perspective

UPDATE: September 22 2009: There is a post on my son’s weblog titled “Incoherence Continues on Adaptation” which provides an excellent example of why we need a broad based, inclusive vulnerability perspective.

I am working to encourage the adoption of the assessment of vulnerability as a focusing approach for the climate community (as well as for colleagues that are involved in other types of environmental research).  This is a much more useful and comprehensive bottom-up, resource-based approach to reduce societal and environmental risk to climate variability and change than relying on the use of multi-decadal global climate model  projections.

I recently summarized this perspective in the following short text:

There are 5 broad areas that we can use to define the need for vulnerability assessments : water, food, energy, health and ecosystem function. Each area has societally critical resources. The vulnerability concept requires the determination of the major threats to these resources from climate, but also from other social and environmental issues. After these threats are identified for each resource, then the relative risk from natural- and human-caused climate change (estimated from the GCM projections, but also the historical, paleo-record and worst case sequences of events) can be compared with other risks in order to adopt the optimal mitigation/adaptation strategy.

The advantage of the bottom-up, resource-based perspective is summarized in Table E.7 in

Pielke, R.A. Sr., and L. Bravo de Guenni, 2004: Conclusions. Chapter E.7 In: Vegetation, Water, Humans and the Climate: A New Perspective on an Interactive System. Global Change – The IGBP Series, P. Kabat et al., Eds., Springer, 537-538.

Pielke, R.A. Sr., 2004: Discussion Forum: A broader perspective on climate change is needed. IGBP Newsletter, 59, 16-19

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Recent Paper “Influence Of Cloud Condensation And Giant Cloud Condensation Nuclei” By Cheng Et Al 2009

Cheng, W. Y. Y., G. G. Carrió, W. R. Cotton, and S. M. Saleeby (2009), Influence of cloud condensation and giant cloud condensation nuclei on the development of precipitating trade wind cumuli in a large eddy simulation, J. Geophys. Res., 114, D08201, doi:10.1029/2008JD011011.

“To investigate the effects of both cloud condensational nuclei (CCN) and giant CCN (GCCN), the Regional Atmospheric Modeling System was used to investigate the effects of various CCN and GCCN concentrations on the development of precipitating trade wind cumuli in a large eddy simulation (LES) framework. The sounding to initialize the LES was taken from the Rain in Cumulus over the Ocean Experiment archive for 11 January 2005. Several sensitivity experiments were performed in which two levels of CCN (GCCN) concentrations were used: 100 (0.01) and 1000 (0.1) per [centimeter cubed] corresponding to low and high values, respectively. Both CCN and GCCN can affect the precipitation processes. With low GCCN concentration, raising the CCN concentration from low to high reduced the precipitation rate as well as the accumulated precipitation due to the presence of a large number of small cloud droplets that are inefficient in forming drizzle. However, GCCN can have a greater response in increasing the precipitation rate and accumulation when the cloud system has a high CCN concentration. The total cloud coverage (TCC) was reduced for the higher CCN concentration experiments because of the susceptibility of evaporation of cloud droplets in the upper parts of the cloud as a result of entrainment. On the other hand, the TCC was increased for the higher GCCN concentration experiments. For this trade wind cumuli case, the time‐ and domain‐averaged albedo changed very slightly with increased [CCN] and/or [GCCN] because of a compensating increase/decrease among the optical depth, liquid water path, cloud coverage, and cloud droplet concentration.”

The conclusions include the text

“Entrainment played a role in affecting the cloud properties and dynamics contrary to Albrecht’s second indirect effect in this case as a result of the different cloud droplet concentrations. The results further illustrate the nonlinear response of clouds to perturbations in aerosol concentrations and that changes in cloud dynamics are just as important as changes in cloud microphysics when examining the radiative responses of clouds to air pollution aerosols.”

This paper provides new insight into one of the complex roles of clouds within the climate system as affected by aerosols.  The indirect effect of aerosols was highlighted as a still very incompletely understood major climate forcing in NRC (2005); see page 40.

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