Monthly Archives: February 2009

A New Paper “Impact Of Deforestation In The Amazon Basin On Cloud Climatology” by Wang Et. Al. 2009

Thanks to Fred Singer for alerting us to the following paper.

Jingfeng Wang, Frédéric J. F. Chagnon, Earle R. Williams, Alan K. Betts, Nilton O. Renno, Luiz A. T. Machado, Gautam Bisht, Ryan Knox, and Rafael L. Bras, 2009: Impact of deforestation in the Amazon basin on cloud climatology. PNAS, published online before print February 23, 2009, doi:10.1073/pnas.0810156106

The abstract is

“Shallow clouds are prone to appear over deforested surfaces whereas deep clouds, much less frequent than shallow clouds, favor forested surfaces. Simultaneous atmospheric soundings at forest and pasture sites during the Rondonian Boundary Layer Experiment (RBLE-3) elucidate the physical mechanisms responsible for the observed correlation between clouds and land cover. We demonstrate that the atmospheric boundary layer over the forested areas is more unstable and characterized by larger values of the convective available potential energy (CAPE) due to greater humidity than that which is found over the deforested area. The shallow convection over the deforested areas is relatively more active than the deep convection over the forested areas. This greater activity results from a stronger lifting mechanism caused by mesoscale circulations driven by deforestation-induced heterogeneities in land cover.”

An extract from the conclusions reads

 “The atmosphere over the study domain behaves more like that over oceans with CAPE dominated by the humidity factor. The forested patches in the Amazon may be viewed as ‘‘green oceans’’ surrounded by ‘continents’. ’Mesoscale circulations induced by the contrast between forested and deforested surfaces with the existing length scales, have been identified as the likely dominant lifting mechanism for convection based on the existing evidence. Boundary layer turbulence appears to play a secondary role in the situation considered in this study. A lack of lifting mechanism is responsible for suppressed convective activity over extensive homogeneous forest surfaces even though CAPE was abundant during the period of study.”

This new  study provides a clear demonstration of the role of landscape both as altering the atmospheric heat and moisture above it, as well as creating atmospheric circulations as a result of fragmented landscape change.

We have published similar conclusions in our papers; e.g. see

Lawton, R.O., U.S. Nair, R.A. Pielke Sr., and R.M. Welch, 2001: Climatic impact of tropical lowland deforestation on nearby montane cloud forests. Science, 294, 584-587.

Nair, U.S., R.O. Lawton, R.M. Welch, and R.A. Pielke Sr., 2003: Impact of land use on Costa Rican tropical montane cloud forests: 1. Sensitivity of cumulus cloud field characteristics to lowland deforestation. J. Geophys. Res. – Atmospheres, 108, 10.1029/2001JD001135

Pielke Sr., R.A., 2001: Influence of the spatial distribution of vegetation and soils on the prediction of cumulus convective rainfall. Rev. Geophys., 39, 151-177.

Pielke, R.A. Sr., J. Adegoke, A. Beltran-Przekurat, C.A. Hiemstra, J. Lin, U.S. Nair, D. Niyogi, and T.E. Nobis, 2007: An overview of regional land use and land cover impacts on rainfall. Tellus B, 59, 587-601.

Ray, D.K., U.S. Nair, R.O. Lawton, R.M. Welch, and R.A. Pielke Sr., 2006: Impact of land use on Costa Rican tropical montane cloud forests. Sensitivity of orographic cloud formation to deforestation in the plains. J. Geophys. Res., 111, D02108, doi:10.1029/2005JD006096.

This topic, of the effect of land use change on climate, was not adequately considered in the 2007 IPCC and 2009 CCSP Reports. This failure is one of the reasons that the policymakers are assuming, erroneously, that the climate is dominated by the radiative forcing of carbon dioxide.

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The Human Effect On The Climate System Involves A Diverse Set Of Heterogeneous Climate Forcings – A Focus On Carbon Dioxide Is Too Narrow

There continues to be a focus on carbon dioxide as the dominate human climate forcing (e.g. see). This is too narrow an approach to how society should reduce its risk to climate, and will have little actual affect on the weather and climate.

In July 2005, Climate Science published a weblog that highlighted the importance of spatial variations in  climate forcings on the weather and climate that we experience. This perspective emphasized that the correct approach to climate policy is to recognize and respond to the actual diversity of human climate forcings. The scientific literature supports the conclusion given below:

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

These forcings include

• The influence of human-caused aerosols on regional (and global) radiative heating
• The effect of aerosols on clouds and precipitation
• The influence of aerosol deposition (e.g. soot; nitrogen) on climate
• The effect of land cover/ land use on climate
• The biogeochemical effect of added atmospheric CO2

This July 2005 weblog What is the Importance to Climate of Heterogeneous Spatial Trends in Tropospheric Temperatures? is repeated today

“The 2005 National Research Council report concluded that:

“regional variations in radiative forcing may have important regional and global climate implications that are not resolved by the concept of global mean radiative forcing.”

And furthermore:

“Regional diabatic heating can cause atmospheric teleconnections that influence regional climate thousands of kilometers away from the point of forcing.”

This regional diabatic heating produces temperature increases or decreases in the layer-averaged regional troposphere. This necessarily alters the regional pressure fields and thus the wind pattern. This pressure and wind pattern then affects the pressure and wind patterns at large distances from the region of the forcing which we refer to as teleconnections.

The regional diabatic forcing can be caused by land-use/land-cover change (e.g. , Chase et al. 2000) or by aerosol emissions. Even natural surface variations such as in ocean color produce such teleconnections in a general circulation model (see Atmospheric response to solar radiation absorbed by phytoplankton )

There is debate, however, regarding whether the magnitude of the regional diabatic forcing is large enough to result in long distance teleconnections. However, observed multi-decadal trends in tropospheric-averaged temperatures are large enough to result in large-scale circulation trends (see, for example, A Comparison of Regional Trends in 1979-1997 Depth-Averaged Tropospheric Temperaturesfor the magnitude of the 1979-1997 regional trends). Thus land-use/land-cover changes and aerosol clouds that produce regional tropospheric temperature anomalies of a similar magnitude (or larger magnitude) would be expected to have significant teleconnection effects.

If this is true, than regional diabatic heating due to human activities represents a major, but under-recognized climate forcing, on long-term global weather patterns. Indeed, this heterogenous climate forcing may be more important on the weather that we experience than changes in weather patterns associated with the more homogeneous spatial radiative forcing of the well-mixed greenhouse gases (see the NASA press release, which is based on the multi-authored paper 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).

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Well-Written News Article Based On A Recent Climate Change Symposum

On February 10 2009, an informative article was published by Takashi Kitazume of The Japan Times. It is titled  “Climate Change Symposum: Rethinking a global post-Kyoto solution –
Initiatives to counter climate change have to be ecologically sustainable and economically viable.

The article reads in part

“New ways of thinking on climate change are needed if the world is to create a workable post-Kyoto Protocol framework to reduce greenhouse gas emissions, European scholars told a recent symposium in Tokyo.

Solutions to climate change must be ecologically sustainable and economically viable, the scholars said, stressing that the participation of all major emitters is crucial to building an effective tool against the rapidly expanding concentrations of carbon dioxide in the atmosphere.

Four experts from Europe spoke at the Jan. 21 symposium organized by the Keizai Koho Center under the theme, “Climate change: Considering post-Kyoto frameworks with European scholars.” Akihiro Sawa, a senior executive fellow at the 21st Century Public Policy Institute, served as moderator of the discussions.

“At the same time, Korhola [Atte Korhola, a University of Helsinki professor] noted that no linear relationship has been established between the increased emissions and the rise in global temperature. “There is absolutely global warming . . . but data also show that global warming has slowed and stabilized during the last 10 years” even as greenhouse gas emissions increased at an unprecedented rate, the professor said.”

“The professor also expressed concern that the target to increase the share of biofuels to 10 percent of energy consumption in transportation ‘can lead to many, many types of ecological disasters.’

“It increases the use of water, increases the price of food, increases deforestation, increases land erosion and degradation,” he said. There may be good solutions to come in the future “but now the EU is forcing us to employ inefficient and very expensive ways to use first-generation biofuels that are causing much more harm than the benefits that are arising from their use,” he added.

Korhola said one of the problems in conventional ways of thinking on global warming is the view that climate change is a pollution problem — just like acid rain or ozone depletion — and that you can solve these environmental problems by legislation.

“That worked with acid rain. It was easy, and relatively cheap to solve the problem of sulfur emissions from factories and energy generation,” the professor said. “But climate change is a totally different problem. . . . It’s a multidimensional problem, not one-dimensional like all previous global environmental problems.”

This is the type of informative news reporting that we need more of!

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New Paper By Lee et al. 2009 on the East Asian Monsoon and the Role of Land Surface Processes

There is yet another paper on the role of landscape as an important weather and climate forcing on the regional scale (and, in this case the global circulation, since the Asian monsoon significantly affects global patterns.

The paper is Lee, E., T. N. Chase, and B. Rajagopalan (2008), Highly improved predictive skill in the forecasting of the East Asian summer monsoon, Water Resour. Res., 44, doi:10.1029/2007WR006514(subscription required for full paper).

The abstract reads

“The East Asian summer monsoon greatly influences the lives and property of about a quarter of the people in the world. However, the predictive skill of the monsoon is very low in comparison with that of the Indian summer monsoon because of the complexity of the system which involves both tropical and subtropical climates. Previous monsoon prediction models emphasized ocean factors as the primary monsoon forcing. Here we show that preseason land surface cover is at least as important as ocean indices. New statistical forecast models of the East Asian summer monsoon using land cover conditions in addition to ocean heat sources double and triple, respectively, the predictive skill of the northern and southern East Asian summer monsoon forecasting models relative to models using ocean factors alone. This work highlights the, as yet, undocumented importance of seasonal land cover in monsoon prediction and the role of the biosphere in the climate system as a whole. We also detail the physical mechanisms involved in these land surface forcings.”

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Another Failure At A Comprehensive Assessment of Climate – The Revised CCSP Report By Karl Et Al 2009

The Second Public review draft of the Unified Synthesis Product (Global Climate Change in the United States) is posted. Comments will be accepted from 13 January through 27 February 2009. See also Federal Register notice. (posted 13 January 2009). The full CCSP report is available.

Climate Science has posted on the first draft of this report; see

http://climatesci.org/2008/08/05/comments-on-ccsp-report-unified-synthesis-product-global-climate-change-in-the-united-states-by-roger-a-pielke-sr/

Comments On CCSP Report Unified Synthesis Product Global Climate Change in the United States By Roger A. Pielke Sr.

CCSP Draft Report Comments as Submitted by Professor Ben Herman of the University of Arizona

Guest Weblog: A Comment On The Report “Unified Synthesis Product Global Climate Change in the United States” By Joseph D. Aleo

 The Co-Editors are

Thomas R. Karl,
NOAA National Climatic Data Center

Jerry M. Melillo,
Marine Biological Laboratory

Thomas C. Peterson,
NOAA National Climatic Data Center

The comments that we provided were not responded to [at least that we can find]. This CCSP report is nothing more than a rehash of the same material as presented in the first version.  If you accept the perspective of the Editors, you can use this report to promote your political agenda.

However, if you want a true balanced perspective of climate issues in the United States, it is not going to satisfy that need. 

The Report is a failure in presenting the diversity of viewpoints that appear in the peer reviewed literature. Policymakers who use this report to promote particular policy actions are either cherry picking for their own advocacy or remain oblivious that there are other scientifically well supported perspectives.

Interested readers can look at the Public Comment that I submitted for the first CCSP report, where the comments regarding how Tom Karl handled that report are certainly applicable to the current report also;

Pielke Sr., Roger A., 2005: Public Comment on CCSP Report “Temperature Trends in the Lower Atmosphere: Steps for Understanding and Reconciling Differences“. 88 pp including appendices.

Also, for an overview as to what is missing in the Karl et al 2009 perspective, see

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.

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Filed under Climate Science Misconceptions, Climate Science Reporting, Uncategorized

Updated CO2 Emission Inventory Provided By Kevin Gurney Of Purdue University

Kevin Gurney of Purdue University has alerted us to a valuable source of information on the emission inventory of CO2 into the atmosphere. Climate Science has weblogged on this Vulcan project previously (see).

The e-mail from Kevin Gurney announcing the release is

Greetings,

Today we are releasing a new version of the Vulcan data product, version 1.1……This version has a number of improvements including an improved area source module, better mobile diurnal emissions representation,and better residential and commercial time structure.

We have also released a portion of the vulcan inventory on Google Earth. You can see information down to the county level by sector and per capita. We included the geocoded powerplant and airport emissions. A flyover has been created and it is up on YouTube at:

http://www.youtube.com/watch?v=Iu-s9IHPGmM

You can also now donate directly to the Vulcan project.

As always, all of the Vulcan information can be accessed from the vulcan website at:

www.purdue.edu/eas/carbon/vulcan

In the associated press release, this project is described further (see). An excerpt reads

“The Vulcan layer on Google Earth shows carbon dioxide emissions in metric tons at the state level, county level and per capita. It also breaks down emissions by the different sectors   the emissions, including aircraft, commercial, electricity production, industrial, residential and transport.”

An important perspective on this climate forcing is also presented in the press release where it is written

“Carbon dioxide is the most important human-produced gas contributing to global climate change, Gurney said.”

Climate Science agrees with this statement as it accurately reflects that the atmospheric concentrations of this gas is the one undergoing the most change from the pre-industrial atmosphere.

What is a critically important next step, however, is to do the same kind of analysis for the other human climate forcings including inventories of the input into the atmosphere and locations of deposition of human-caused aerosols including sulphates, nitrogen compounds and soot, as well as of the alteration of the landscape by human management in terms of how the surface fluxes of heat, moisture, momentum and trace gases such as carbon dioxide are altered.

Such a comphrehensive inventory would provide policymakers with information on all of the first order human climate forcings. This inventory is needed since, as reported in testimony to Congress (see) and concluded in a National Research Council Report (see)

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

 

 

 

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New Plans To Regulate CO2 As A Pollutant

There is renewed emphasis on the need to regulate CO2 as a pollutant; e.g. see

US EPA To Reconsider Pollution Ruling On CO2

BREAKING: Obama Pledges to Regulate CO2 from Coal Plants

Climate Science has weblogged in the past on this issue:

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

A Carbon Tax For Animal Emissions – More Unintended Consequences Of Carbon Policy In The Guise Of Climate Policy

Will Climate Effects Trump Health Effects In Air Quality Regulations?

Supreme Court Rules That The EPA Can Regulate CO2 Emissions

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

The regulation of CO2 will open a pandora’s box with respect to government regulation. The text in the most recent weblog on this subject stated that

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

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

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Meeting Summary “Global Warming And The Next Ice Age” By Dubey Et Al 2008

Climate Science has weblogged about a meeting Global Warming and the Next Ice Age that was held in Santa Fe, New Mexico July 17-21 2006; i.e. see, see, see, and see.

The AMS Bulletin of the American Meterological Society has published a summary of this meeting in its December 2008 issue;

 Manvendra K. Dubey, Charlie S. Zender, Chris K. Folland, and Petr Chylek, 2008: Global Warming and the Next Ice Age. Bulletin of the American Meteorological Society, pp. 1905–1909. DOI: 10.1175/2008BAMS2359.1.

The goal of the meeting was that

“More than 120 scientists from 14 countries with expertise in the observation, theory, and
modeling of climate change met to discuss how Earth’s climate responds to non–greenhouse gas forcings, and how to improve predictions of these responses.”

The BAMS meeting summary starts with the text

“Earth’s climate is a complex dynamical system that is responding to an array of forcings, which include anthropogenic carbon dioxide and aerosols and solar variability. Aeorsol and solar forcings are imperfectly constrained and only monitored by observational systems with limited sensitivity and coverage.”

Among the conclusions of the meeting, as written at the end of the BAMS article is that

“It was determined during this conference that the optimal path to reduce uncertainties and increase precision of climate change forecasts is by bringing in observations to inform, test, and refine climate models. This is particularly important for aerosols and clouds, which are complex and influence the planetary albedo and radiation budget significantly. Progress is being made and the outlook it good since many aerosol-cloud perturbations and processes operate on shorter time scales rendering them measurable. However, this is a daunting task for other longer-term feedbacks such as ocean–ice–atmosphere changes where our community will have to use paleoclimate data or gather longer records to validate climate models, an interaction that our meeting also catalyzed. Observationalists and modelers (Xiao and Li 2007) must play a synergistic role in climate change research to increase the precision of climate forecasts for future energy options.”

A unique aspect of this meeting was that it was inclusive and permitted the spectrum of viewpoints on climate to be presented.  This balance is often lacking in other meetings, as documented recently on Cliamte Science; e.g. see

Protecting The IPCC Turf – There Are No Independent Climate Assessments Of The IPCC WG1 Report Funded And Sanctioned By The NSF, NASA Or The NRC.

We need more such balanced, inclusive conferences as summarized in the 2008 BAMS article.

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A New Paper “The Impact Of Agricultural Intensification And Irrigation On Land–Atmosphere Interactions And Indian Monsoon Precipitation —A Mesoscale Modeling Perspective by Douglas et al 2009

We have in press another peer reviewed paper that demonstrates the role of land surface processes as a first order climate forcing as well as an integral component of any assessment of climate variability and change [our study complements the peer reviewed paper by Lee et al which was weblogged on Climate Science on January 30 2009].

The paper is

Douglas, E.M., A. Beltrán-Przekurat, D. Niyogi, R.A. Pielke, Sr., and C. J. Vörösmarty, 2009: The impact of agricultural intensification and irrigation on land–atmosphere interactions and Indian monsoon precipitation —A mesoscale modeling perspective, Glob. Planet. Change, doi:10.1016/j.gloplacha.2008.12.007 [see this link also for the paper].

The abstract reads 

“Using the Regional Atmospheric Modeling System (RAMS) we show that agricultural intensification and irrigation can modify the surface moisture and energy distribution, which alters the boundary layer and regional convergence, mesoscale convection, and precipitation patterns over the Indian monsoon region. Four experiments were conducted to simulate a rain event from 16 to 20 July 2002 over the Indian region: (i) a control with Global Land Cover land use and observed Normalized Difference Vegetation Index, (ii) an irrigated crop scenario, (iii) a non-irrigated crop scenario, and (iv) a scenario for potential (natural) vegetation. Results indicate that even under active monsoon conditions, the simulated surface energy and moisture flux over the Indian monsoon region are sensitive to the irrigation intensity and this effect is more pronounced than the impact of land use change from the potential vegetation to the agricultural landscape. When model outputs were averaged over the south Asia model domain, a statistically significant decrease in mean sensible heat flux between the potential vegetation and the irrigated agriculture scenarios of 11.7 W m-2 was found. Changes in latent heat fluxes ranging from -20.6 to +37.2 W m-2 (-26% to +24%) and sensible heat fluxes ranging -87.5 to +4.4 W m-2 (-77% to +8%) fluxes were found when model outputs were averaged over Indian states. Decreases in sensible heat in the states of Punjab (87.5 W m-2 or 77%) and Haryana (65.3 W m-2 or 85%) were found to be statistically significant at the 95% confidence level. Irrigation increased the regional moisture flux which in turn modified the convective available potential energy. This caused a reduction in the surface temperature and led to a modified regional circulation pattern and changes in mesoscale precipitation. These agricultural changes, including irrigation modify the mesoscale convection and rain patterns in the Indian monsoon region. These regional changes in land use need to be considered in improved weather forecasting as well as multi-decadal climate variability and change assessments.”

An excerpt from the Summary and Conclusions reads

“The growth in human population has increased the demand food supplies leading to intensified agriculture worldwide. The consequent changes in agricultural practices can lead to alterations in the landscape via changes in the land-use land-cover including irrigation……Irrigation increased the regional moisture flux which in turn modified the convective available potential energy (CAPE), caused reduction in the surface temperature and led to a modified regional circulation pattern and changes in mesoscale precipitation. It is anticipated that agricultural changes, and irrigation impacts, can modify the regional climate and the mesoscale convection and rain patterns in the Indian monsoon region and need to be considered in multi-decadal climate variability and change assessments.”

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Importance Of Land Use Versus Atmospheric Information Verified From Cloud Simulations From The Monteverde Frontier Region of Costa Rica” by Ray et al. 2009

We have another paper accepted for publication which examines the importance of land use and of atmospheric information with respect to mesoscale and regional weather and climate predictions. It is

Ray, D. K., R. A. Pielke Sr., U. S. Nair, R. M. Welch, and R. O. Lawton (2009). Importance of land use versus atmospheric information verified from cloud simulations from a frontier region in Costa Rica, J. Geophys. Res., doi:10.1029/2007JD009565, in press

The abstract reads

“Land-use/land-cover (LULC) change has been recognized as a key component in global climate change and numerous climate modeling studies at regional to global scales document this. The research strategies have invariably been to first conduct baseline simulations of current conditions to evaluate model performance. Then simulation of regional climate with land cover changes (LCC) implemented within the model allows differences with the baseline simulation to be used as evidence of global to regional-scale climate impacts of LCC.

However, even state-of-the-art regional climate models require two datasets to conduct reasonable baseline simulations. These are representative current land cover and atmospheric information over the study region. In frontier and developing areas (where most of the rapid land-use conversion is taking place), these datasets are frequently unavailable and the errors in simulations are either due to inaccurate land cover, insufficient atmospheric information, non-representative model physics, or a combination of one or more of the above. This study shows that in one frontier region, that surrounding the Cordillera de Tilarán of Costa Rica, the accuracy of simulating clouds decreases by 1% to 3% if default model land cover information is used. If the atmospheric datasets used are the ones usually available to researchers (with land cover information held constant), then the model accuracy is reduced by 21% to 25%. Model runs without updated land cover or atmospheric information reduces model accuracy slightly further. Precipitation comparisons also provided similar results.

This study thus shows that the critically important dataset for conducting accurate simulations is not land cover information but atmospheric information. Researchers may similarly get significant increase in the accuracy of their baseline simulations elsewhere by using radiosondes/rawinsondes over their study region. Finally, since atmospheric information is not available for different landscape scenarios, assessments of the relative role of LULC change will have to continue to rely on using the standard atmospheric data set and the acceptance that the use of more detailed atmospheric data to initialize and provide lateral boundary conditions would have reduced the uncertainties in such landscape sensitivity studies.”

An excerpt from the paper reads

“From this study, however, it is quite clear that changes in land cover and atmospheric information will result in changes in simulation accuracy……..With respect to assessing the relative role of land-use change on the climate system, the improved simulation accuracy with better atmospheric structure information has an important implication. Since atmospheric information, of course, is not available for different landscape scenarios, (i.e. simulations are one-way nested regional model integrations in which there is no interaction from the regional to the large scales through the lateral boundaries) assessments of the relative role of LULC change will still have to rely on either using the standard atmospheric data set or on the use of more detailed atmospheric data over the current landscape even though it is affected by the current landscape for initial and lateral boundary conditions. The latter approach will reduce the simulation differences expected in such landscape sensitivity studies since the initial atmospheric conditions with a different landscape would in reality, of course, be different.”

This study is relevant to dynamic regional downscaling from global models, which a technique used to obtain local climate change impact information (see). What is can be concluded from this study is that even with the best land surface information, if the atmospheric information being transmitted into the regional model through lateral boundary conditions is not accurate, the impact assessment will, necessarily, be erroneous. 

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