Kevin Trenberth has followed up his weblog on the Nature site Climate Feedback - The Climate Change Blog entitled “Predictions of climate” with a weblog on the subject of climate prediction. This new posting is entitled
Global Warming and Forecasts of Climate Change.
Unfortunately, this new post lacks the candor that is in the original Nature weblog by Kevin Trenberth on this subject (as discussed on Climate Science ; see).
The current weblog makes several misleading statements with respect to the ability to “project” climate change with the multi-decadal global climate models.
First, Trenberth writes,
“In particular there is clear evidence (“warming is unequivocalâ€?) that climate is changing in ways consistent with the climate forcings. Also, the projections are for all aspects of climate, not just global mean temperature.”
This obviously contradicts his statement in his first Nature weblog where he writes
“However, the science is not done because we do not have reliable or regional predictions of climate.”
The model results cannot be “consistent” if they are not reliable and are also not regional in scale!
Second, he writes,
“The same atmospheric models are the atmospheric component of climate models and they are well tested and evaluated, although in climate models lower resolution is used.”
This is true (except the weather models typically do not include atmospheric gaseous and aerosol chemistry which is required in a multi-decadal global climate model). However, as he writes in his first weblog,
“None of the models used by IPCC are initialized to the observed state and none of the climate states in the models correspond even remotely to the current observed climate. In particular, the state of the oceans, sea ice, and soil moisture has no relationship to the observed state at any recent time in any of the IPCC models. There is neither an El Niño sequence nor any Pacific Decadal Oscillation that replicates the recent past; yet these are critical modes of variability that affect Pacific rim countries and beyond. The Atlantic Multidecadal Oscillation, that may depend on the thermohaline circulation and thus ocean currents in the Atlantic, is not set up to match today’s state, but it is a critical component of the Atlantic hurricanes and it undoubtedly affects forecasts for the next decade from Brazil to Europe. Moreover, the starting climate state in several of the models may depart significantly from the real climate owing to model errors. I postulate that regional climate change is impossible to deal with properly unless the models are initialized.”
His own words present a very different perspective than given on his new weblog. The atmospheric models may be the same, but the other components of the climate model (ocean, land, cryosphere) are poorly represented!
Third, he writes,
“The authors should recognize that IPCC does not make forecasts but rather makes projections to guide policy and decision makers.”
This is disingenuous to suggest to readers that a forecast and a projection are any different; see
Pielke Sr., R.A., 2002: Overlooked issues in the U.S. National Climate and IPCC assessments. Climatic Change, 52, 1-11
He continues by seeking to separate a forecast from a projection because with a projection
“If those changes are considered undesirable, it can create efforts to change that outcome.”
This is obviously true of forecasts too (weather modification, for example, could change a forecast for rain, but the term projection is never used in this context). The term “projection� is only introduced, rather than forecasts, to obscure that the multi-decadal global models do not have predictive skill!
It should be clear in his new Nature weblog that, unfortunately, his candid comments in this earlier weblog resulted in negative feedback from his colleagues such that he felt compelled to follow up with a poor summary of climate forecasting. This is unfortunate, as his original weblog was a bridge that can be used to advance climate science.
Thanks to Sallie Sprague for alerting me (through an Long Term Ecological Research - LTER project I am on) to an interesting new paper that has been published in the April 2007 issue of New Phytologist.
The article is
William J. Parton, Jack A. Morgan, Guiming Wang, Stephen Del Grosso
Projected ecosystem impact of the Prairie Heating and CO2 Enrichment experiment New Phytologist (OnlineEarly Articles). doi:10.1111/j.1469-8137.2007.02052.x
The abstract reads
“The Prairie Heating and CO2 Enrichment (PHACE) experiment has been initiated at a site in southern Wyoming (USA) to simulate the impact of warming and elevated atmospheric CO2 on ecosystem dynamics for semiarid grassland ecosystems.
The DAYCENT ecosystem model was parameterized to simulate the impact of elevated CO2 at the open-top chamber (OTC) experiment in north-eastern Colorado (1996–2001), and was also used to simulate the projected ecosystem impact of the PHACE experiments during the next 10 yr.
Model results suggest that soil water content, plant production, soil respiration, and nutrient mineralization will increase for the high-CO2 treatment. Soil water content will decrease for all years, while nitrogen mineralization, soil respiration, and plant production will both decrease and increase under warming depending on yearly differences in water stress. Net primary production (NPP) will be greatest under combined warming and elevated CO2 during wet years.”
Model results are consistent with empirical field data suggesting that water and
nitrogen will be critical drivers of the semiarid grassland response to global change.”
This paper demonstrates that the effect of climate variability and change on the grassland must consider much more than the global average surface temperature, and even the local temperature. The paper also emphasizes the need to consider CO2’s biogeochmical climate forcing, as well as its radiative forcing. The need for better understanding of this complexity was emphasized in the 2005 National Research Council Report “Radiative Forcing of Climate Change: Expanding the Concept and Addressing Uncertainties” which has been discussed many times on Climate Science.
The news release on this paper, however, inserts the customary attribution to “global warming”. No where in the Parton et al paper is this term even used! The paper reports on the effect of perturbations of different environmental stressors on the grassland including local air temperature increases, but it does not (and cannot) relate directly to global average climate system heat changes (i.e. “global warming”).
The news release reads as follows (and except for the alluding to “global warming”) is a good report.
“Global warming will have mixed effects on eastern Colorado’s grasslands April 23, 2007
New research results from Colorado State University suggest that the effects of rising atmospheric concentrations of carbon dioxide and global warming will lead to an increase in grass production and a decline in forage quality for grasslands of eastern Colorado and Wyoming.
Study results suggest that both elevated CO2 and warming will increase grass production but the quality of the vegetation will decrease due to lower nitrogen concentration in the forage. William Parton, researcher from Colorado State’s Natural Resource Ecology Laboratory, or NREL, and researcher Jack Morgan from the U.S. Department of Agriculture’s Agricultural Research Service, USDA ARS, studied the effects of warming, increased CO2 levels and the combination of both factors on eastern Colorado grasslands to predict how global warming will affect these ecosystems.
Warming can have both positive and negative impacts on plant production
Results revealed that elevated atmospheric CO2 levels always increase grass growth; however, warming can have both positive and negative impacts on plant production.
‘The potential impact of elevated CO2 levels on Colorado and Wyoming grasslands is mixed since grass production will likely increase while digestibility of forage and cattle weight gains will likely decrease,’ Parton said. ‘Increased air temperatures will have a mixed impact with plant production increasing in wet years and decreasing in dry years.’
These predictions are based on results from an ecosystem model developed using data from locally observed climatic change experiments that will continue during the next five to 10 years.
Experiments combined with ecosystem models
In this experiment, Colorado State and ARS scientists were able to use empirical knowledge from relatively short-term experiments combined with ecosystem models to predict long-term ecosystem responses to the effects of global warming. The scientists used results from a five-year-long CO2 enrichment experiment conducted in northern Colorado to test CO2 impacts in the Daycent ecosystem model. They also used field data from the experiment site, Prairie Heating and CO2 Enrichment or PHACE, located in southern Wyoming that will continue for the next five to 10 years.
‘One of our biggest challenges is how to interpret relatively short-term experiments and predict the long-term global warming consequences on grasslands,’ Morgan said. ‘By taking the results from our field experiments and applying computer models tested using the observed field data, we are able to extrapolate beyond our short-term experiments into the future.’
Critical matter for livestock and native prairie animals
The scientists observed that doubling CO2 levels caused strong and consistent increases in grass growth which was due to improved water-use efficiency. Under the elevated CO2 levels, it was also found that plant nitrogen content was declining in native grasslands. This is a critical matter for livestock and for native animals that have grazed these prairies for thousands of years. Increased CO2 dilutes nitrogen concentration in grazing vegetation. Animals require sufficient forage protein nitrogen to sustain normal weight gains.”
Among the findings of the 2005 National Research Council report
Radiative Forcing of Climate Change: Expanding the Concept and Addressing Uncertainties
are
I. “Determine the Importance of Regional Variation in Radiative Forcing
Regional variations in radiative forcing may have important regional and global climatic implications that are not resolved by the concept of global mean radiative forcing. Tropospheric aerosols and landscape changes have particularly heterogeneous forcings. To date, there have been only limited studies of regional radiative forcing and response. Indeed, it is not clear how best to diagnose a regional forcing and response in the observational record; regional forcings can lead to global climate responses, while global forcings can be associated with regional climate responses. Regional diabatic heating can also cause atmospheric teleconnections that influence regional climate thousands of kilometers away from the point of forcing. Improving societally relevant projections of regional climate impacts will require a better understanding of the magnitudes of regional forcings and the associated climate responses.
PRIORITY RECOMMENDATIONS:
Use climate records to investigate relationships between regional radiative forcing (e.g., land-use or aerosol changes) and climate response in the same region, other regions, and globally.
Quantify and compare climate responses from regional radiative forcings in different climate models and on different timescales (e.g., seasonal, interannual), and report results in climate change assessments.
II. Determine the Importance of Nonradiative Forcings
Several types of forcings—most notably aerosols, land-use and land-cover change, and modifications to biogeochemistry—impact the climate system in nonradiative ways, in particular by modifying the hydrological cycle and vegetation dynamics. Aerosols exert a forcing on the hydrological cycle by modifying cloud condensation nuclei, ice nuclei, precipitation efficiency, and the ratio between solar direct and diffuse radiation received. Other nonradiative forcings modify the biological components of the climate system by changing the fluxes of trace gases and heat between vegetation, soils, and the atmosphere and by modifying the amount and types of vegetation. No metrics for quantifying such nonradiative forcings have been accepted. Nonradiative forcings have eventual radiative impacts, so one option would be to quantify these radiative impacts. However, this approach may not convey appropriately the impacts of nonradiative forcings on societally relevant climate variables such as precipitation or ecosystem function. Any new metrics must also be able to characterize the regional structure in nonradiative forcing and climate response.
PRIORITY RECOMMENDATIONS:
Improve understanding and parameterizations of aerosol-cloud thermodynamic interactions and land-atmosphere interactions in climate models in order to quantify the impacts of these nonradiative forcings on both regional and global scales.
Develop improved land-use and land-cover classifications at high resolution for the past and present, as well as scenarios for the future.”
Did the IPCC WG1 Statement for Policymakers adequately discuss these issues? The answer is NO. However, these topics are discussed in Chapter 7, where, for example, it is written,
“The consequences of changes in atmospheric heating from land changes at a regional scale are similar to those from ocean temperature changes such as from El Niño, potentially producing patterns of reduced or increased cloudiness and precipitation elsewhere to maintain global energy balance. Attempts have been made to find remote adjustments (e.g., Avissar and Werth, 2005). Such adjustments may occur in multiple ways, and are part of the dynamics of climate models. The locally warmer temperatures can lead to more rapid vertical decreases of atmospheric temperature so that at some level overlying temperature is lower and radiates less. The net effect of such compensations is that averages over larger areas or longer time scales commonly will give smaller estimates of change. Thus, such regional changes are better described by local and regional metrics or at larger scales by measures of change in spatial and temporal variability rather than simply in terms of a mean global quantity.”
Why was not this conclusion headlined in the policy statement that was transmitted to the politicians?
Chapter 8 of the IPCC Report is much more 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, as with Part I (see and see) 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.
This cross-referencing is given below where a bold face means that it appeared in the IPCC Report and the Chapter in which it appears is given. The IPCC Chapters referred to below have the titles
Chapter 2 Changes in Atmospheric Constituents and in Radiative Forcing
Chapter 6 Palaeoclimate
Chapter 7 Couplings Between Changes in the Climate System and Biogeochemistry
Chapter 8 Climate Models and their Evaluation
Chapter 10 Global Climate Projections
Chapter 11 Regional Climate Projections
II. ROLE OF LAND-USE CHANGE AS A MAJOR CLIMATE FORCING
Avissar, R., and Y. Liu, 1996: Three-dimensional numerical study of shallow convective clouds and precipitation induced by land surface forcing. J. Geophys. Res., 101(D3), 7499-7518, 10.1029/95JD03031.
Avissar, R., and D. Werth, 2005: Global hydroclimatological teleconnections resulting from. tropical deforestation. J. Hydrometeor., 6, 134–145. IN CHAPTER 7 & CHAPTER 11
Brovkin, V., M. Claussen, E. Driesschaert, T. Fichefet, D. Kicklighter, M. F. Loutre, H. D. Matthews, N. Ramankutty, M. Schaeffer, and A. Sokolov, 2006: Biogeophysical effects of historical land cover changes simulated by six Earth system models of intermediate complexity. Climate Dynamics, 1-14, DOI: 10.1007/s00382-005-0092-6. IN CHAPTER 2 & CHAPTER 8
Cai, M., and E. Kalnay, 2004: Response to the comments by Vose et al. and Trenberth. Impact of land-use change on climate, Nature, 427, 214, doi:10.1038/427214a.
Chase, T.N., R.A. Pielke, T.G.F. Kittel, R.R. Nemani, and S.W. Running, 2000: Simulated impacts of historical land cover changes on global climate in northern winter. Climate Dynamics, 16, 93-105. IN CHAPTER 2 & CHAPTER 11
Chase, T.N., R.A. Pielke, Sr., T.G.F. Kittel, M. Zhao, A.J. Pitman, S.W. Running, and R.R. Nemani, 2001: The relative climatic effects of landcover change and elevated carbon dioxide combined with aerosols: A comparison of model results and observations. J. Geophys. Res., Atmospheres, 106, 31,685 -31,691.
Claussen, M., C. Kubatzki, V. Brovkin, A. Ganopolski, P. Hoelzmann, H.-J. Pachur, 1999; Simulation of an abrupt change in Saharan vegetation in the mid-Holocene. Geophys. Res. Lett., 26(14), 2037-2040, 10.1029/1999GL900494. IN CHAPTER 6, CHAPTER 10 & CHAPTER 11
Cotton, W.R. and R.A. Pielke, 2007: Human impacts on weather and climate. Cambridge University Press, 330 pp.
Cox, P. M., R. A. Betts, C. D. Jones, S. A. Spall, and I. J. Totterdell, 2000: Acceleration of global warming due to carbon-cycle feedbacks in a coupled climate model. Nature, 408, 184-187. IN CHAPTER 7, CHAPTER 8, CHAPTER 10 & CHAPTER 11
Cui, X., H.-F. Graf, B. Langmann, W. Chen, and R. Huang, 2006: Climate impacts of anthropogenic land use changes on the Tibetan Plateau, Global and Planetary Change, 54, 1-2, 33-56.
Eastman, J.L., M.B. Coughenour, and R.A. Pielke, 2001: The effects of CO2 and landscape change using a coupled plant and meteorological model. Global Change Biology, 7, 797-815.
Eugster, W., W.R. Rouse, R.A. Pielke, J.P. McFadden, D.D. Baldocchi, T.G.F. Kittel, F.S. Chapin III, G.E. Liston, P.L. Vidale, E. Vaganov, and S. Chambers, 2000: Land-atmosphere energy exchange in Arctic tundra and boreal forest: available data and feedbacks to climate. Global Change Biology, 6, 84-115.
Feddema, J.J., K.W. Oleson, G.B. Bonan, L.O. Mearns, L.E. Buja, G.A. Meehl, and W.M. Washington, 2005: The importance of land-cover change in simulating future climates. Science, 310, 1674-1678. IN CHAPTER 10
Foley, J.A., R. DeFries, G.P. Asner, C. Barford, G. Bonan, S.R. Carpenter, F.S. Chapin, M.T. Coe, G.C. Daily, H.K. Gibbs, J.H. Helkowski, T. Holloway, E.A. Howard, C.J. Kucharik, C. Monfreda, J.A. Patz, I.C. Prentice, N. Ramankutty, and P.K. Snyder, 2005: Global consequences of land use. Science, 309, 570-574. IN CHAPTER 11
Friedlingstein P., L. Bopp, P. Ciais, J.-L Dufresne, L. Fairhead, H. LeTreut, P. Monfray, and J. Orr, 2001: Positive feedback between future climate change and the carbon cycle. Geophys. Res. Lett., 28, 1543-1546. IN CHAPTER 7, CHAPTER 8, & CHAPTER 11
Gero, A.F., A.J. Pitman, G.T. Narisma, C. Jacobson, and R.A. Pielke Sr., 2006: The impact of land cover change on storms in the Sydney Basin. Global and Planetary Change, 54, 57-78.
Gibbard, S., K. Caldeira, G. Bala, T. J. Phillips, and M. Wickett, 2005: Climate effects of global land cover change. Geophys. Res. Lett., 32, L23705, doi:10.1029/2005GL024550.
Hoffmann, W.A., and R.B. Jackson, 2000: Vegetation-climate feedbacks in the conversion of tropical savanna to grassland. J. Climate, 13, 1593–1602.
Holt, T.R., D. Niyogi, F. Chen, K. Manning, M.A. LeMone, and A. Qureshi, 2006: Effect of land–atmosphere interactions on the IHOP 24–25 May 2002 convection case. Mon. Wea. Rev., 134, 113–133.
Kleidon, A., 2006: The climate sensitivity to human appropriation of vegetation productivity and its thermodynamic characterization. Global and Planetary Change, 54, 109-127. doi:10.1016/j.gloplacha.2006.01.016
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.
Lee, E., R.S. Oliveira, T.E. Dawson, and I. Fung, 2005: Root functioning modifies seasonal climate. Proceedings of the National Academy of Sciences, 102, no. 49, 17576-17581.
Mahmood, R., S.A. Foster, T. Keeling, K.G. Hubbard, C. Carlson and R. Leeper, 2006: Impacts of irrigation on 20th century temperature in the northern Great Plains. Global and Planetary Change, 54, 1-18. doi:10.1016/j.gloplacha.2005.10.004.
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. IN CHAPTER 11
Marshall, C.H. Jr., R.A. Pielke Sr., L.T. Steyaert, and D.A. Willard, 2004: The impact of anthropogenic land-cover change on the Florida peninsula sea breezes and warm season sensible weather. Mon. Wea. Rev., 132, 28-52.
Marshall, C.H., R.A. Pielke Sr., and L.T. Steyaert, 2004: Has the conversion of natural wetlands to agricultural land increased the incidence and severity of damaging freezes in south Florida? Mon. Wea. Rev., 132, 2243-2258.
Millán, M. M., Mª. J. Estrela, M. J. Sanz, E. Mantilla, M. MartÃn, F. Pastor, R. Salvador, R. Vallejo, L. Alonso, G. Gangoiti, J.L. Ilardia, M. Navazo, A. Albizuri, B. Artiñano, P. Ciccioli, G. Kallos, R.A. Carvalho, D. Andrés, A. Hoff, J. Werhahn, G. Seufert, B, Versino, 2005: Climatic Feedbacks and Desertification: The Mediterranean model. J. Climate, 18 (5), 684-701.
Myhre, G., Y. Govaerts, J. M. Haywood, T. K. Berntsen, and A. Lattanzio, 2005:Radiative effect of surface albedo change from biomass burning. Geophys. Res. Lett., 32, L20812, doi:10.1029/2005GL022897.
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.
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. Referenced as Jacob et al. in the IPCC; IN CHAPTER 2
Nemani, R.R., S.W. Running, R.A. Pielke, and T.N. Chase, 1996: Global vegetation cover changes from coarse resolution satellite data. J. Geophys. Res., 101, 7157-7162.
Niyogi, D., T. Holt, S. Zhong, P.C. Pyle, and J. Basara, 2006: Urban and land surface effects on the 30 July 2003 mesoscale convective system event observed in the southern Great Plains. J. Geophys. Res., 111, D19107, doi:10.1029/2005JD006746.
Notaro, M., Z. Liu, R. Gallimore, S.J. Vavrus, J.E. Kutzbach, I.C. Prentice, and R.L. Jacob, 2005: Simulated and observed preindustrial to modern vegetation and climate changes. J. Climate, 18, 3650–3671.
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. IN CHAPTER 7
Pielke Sr., R.A., 2005: Land use and climate change. Science, 310, 1625-1626.
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. IN CHAPTER 2 & CHAPTER 11
Pitman, A.J., G.T. Narisma, R.A. Pielke Sr., and N.J. Holbrook, 2004: The impact of land cover change on the climate of southwest western Australia. J. Geophys. Res., 109, D18109, doi:10.1029/2003JD004347.
Ramunkutty, N., C. Delire and P. Snyder, 2006: Feedbacks between agriculture and climate: An illustration of the potential unintended consequences of human land use activities. Global and Planetary Change, 54, 1-2, 79-93, doi:10.1016/j.gloplacha.2005.10.005
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, doi:10.1029/2005JD006096.
Ray, D.K., R.M. Welch, R.O. Lawton, and U.S. Nair, 2006: Dry season clouds and rainfall in northern Central America: Implications for the Mesoamerican Biological Corridor. Global and Planetary Change, 54, 150-162.
Salmun, H., and A. Molod, 2006: Progress in modeling the impact of land cover change on the global climate. Progress in Physical Geography, 30, 737–749.
Sturm, M., T. Douglas, C. Racine, and G.E. Liston, 2005: Changing snow and shrub conditions affect albedo with global implications. J. Geophys. Res., 110, G01004, doi:10.1029/2005JG000013. IN CHAPTER 7
TerMaat, H.W., R.W.A. Hutjes, R. Ohba, H. Ueda, B. Bisselink and T. Bauer, 2006: Meteorological impact assessment of possible large scale irrigation in Southwest Saudi Arabia. Global and Planetary Change, 54, 183-201.
Timbal, B., and J.M. Arblaster, 2006: Land cover change as an additional forcing to explain the rainfall decline in the south west of Australia. Geophys. Res. Lett., 33, L07717, doi:10.1029/2005GL025361.
van der Molen, M.K., A.J. Dolman, M.J. Waterloo and L.A. Bruijnzeel, 2006: Climate is affected more by maritime than by continental land use change: A multiple scale analysis. Global and Planetary Change, 54, 128-149.
Werth, D., and R. Avissar, 2002: The local and global effects of Amazon deforestation. J. Geophys. Res., 107, 8087, doi:10.1029/2001JD000717
Here are several summary points from this assessment:
1. The 2005 NRC Report was only cited in one chapter (Chapter 2), and its recommendations are not considered in any of the following chapters.
2. None of the papers were cited in Chapter 9 which is entitled “Understanding and Attributing Climate Change“. As documented in the papers listed above, the attribution of climate change cannot be accurately accomplished without including land surface processes, including land use change.
3. The important role of land surface processes in the IPCC chapters is presented in a sporadic fashion without the needed focused evaluation of its role, as recommended in the 2005 NRC Report. The 2007 IPCC Report did not adequately honor the charge of the IPCC WG1 Report to provide “A comprehensive and rigourous picture of the global present state of knowledge of climate change”.
Finally, if one suggests that the set of papers that were referenced in the IPCC report are a representative sample that cover the range of issues with the role of land surface processes (which Climate Science concludes is not the case), than refer us to the text in the IPCC report that addresses the issue of the importance of regional radiative and non-radiative climate forcings on the climate system. The IPCC Report fails on this much needed assessment of the role of humans in the climate system.