The Regional Evapotranspiration of the Amazon

Abstract The annual cycle of evapotranspiration (ET) is an important component of the Amazon hydrological balance, which is of critical importance to the global water cycle. Understanding the changing water balance in this region is particularly important to estimate future global and regional hydroclimate change in response to projected deforestation of the rain forest in this region. Several methods have been used to estimate the annual ET cycle in the Amazon basin. These different methods, which result in a spread of annual means, ranges, and phases of the ET cycle, are evaluated here. In an attempt to reconcile the differences between them, both the data and the assumptions upon which the methods are based are scrutinized. The differences seem to originate from the geographic site where radiation and ET are simulated and/or observed and, more significantly, from the way that vegetation controls ET in the different models being used. While field campaigns conducted during the Large-Scale Biosphere Atmo...

[1]  E. Davidson,et al.  The role of deep roots in the hydrological and carbon cycles of Amazonian forests and pastures , 1994, Nature.

[2]  Nancy A. Ritchey,et al.  Seasonal variation of surface radiation budget derived from International Satellite Cloud Climatology Project C1 data , 1992 .

[3]  Pedro Leite da Silva Dias,et al.  The Large‐Scale Biosphere‐Atmosphere Experiment in Amazonia (LBA): Insights and future research needs , 2002 .

[4]  H. Pan,et al.  Interaction between soil hydrology and boundary-layer development , 1987 .

[5]  M. Hodnett,et al.  Seasonal soil water storage changes beneath central Amazonian rainforest and pasture , 1995 .

[6]  C. W. Thornthwaite.  An approach toward a rational classification of climate. , 1948 .

[7]  Piers J. Sellers,et al.  Amazonian Deforestation and Regional Climate Change , 1991 .

[8]  J. Monteith,et al.  Boundary Layer Climates. , 1979 .

[9]  G. Schmidt,et al.  Simulation of recent northern winter climate trends by greenhouse-gas forcing , 1999, Nature.

[10]  Peter H. Stone,et al.  Efficient Three-Dimensional Global Models for Climate Studies: Models I and II , 1983 .

[11]  Yale Mintz,et al.  Climatology of the terrestrial seasonal water cycle , 1985 .

[12]  R. Reynolds,et al.  The NCEP/NCAR 40-Year Reanalysis Project , 1996, Renewable Energy.

[13]  C. Nobre,et al.  Preface to special issue on the Large‐Scale Biosphere‐Atmosphere Experiment in Amazonia (LBA) , 2002 .

[14]  Yogesh C. Sud,et al.  Intercomparison of hydrologic processes in AMIP GCMs , 1996 .

[15]  Humberto Ribeiro da Rocha,et al.  Modelling surface conductance for Amazonian pasture and forest , 1996 .

[16]  Andrea N. Hahmann,et al.  RCCM2–BATS Model over Tropical South America: Applications to Tropical Deforestation , 1997 .

[17]  Nathan Phillips,et al.  Survey and synthesis of intra‐ and interspecific variation in stomatal sensitivity to vapour pressure deficit , 1999 .

[18]  D. Nepstad,et al.  Deep Soil Moisture Storage and Transpiration in Forests and Pastures of Seasonally-Dry Amazonia , 1998 .

[19]  Ann Henderson-Sellers,et al.  Modelling tropical deforestation: A study of GCM land-surface parametrizations , 1988 .

[20]  Ann Henderson-Sellers,et al.  Tropical deforestation: Modeling local‐ to regional‐scale climate change , 1993 .

[21]  W. J. Shuttleworth,et al.  Evaporation from Amazonian rainforest , 1988, Proceedings of the Royal Society of London. Series B. Biological Sciences.

[22]  C. Rosenzweig,et al.  Land-Surface Model Development for the GISS GCM , 1997 .

[23]  Makiko Sato,et al.  Chapter 4 – Climate Modeling in the Global Warming Debate , 2000 .

[24]  Jan Polcher,et al.  A Comparison of Amazonian Climate Data with General Circulation Model Simulations , 1998 .

[25]  M. Caldwell,et al.  Hydraulic lift: consequences of water efflux from the roots of plants , 1998, Oecologia.

[26]  Roni Avissar,et al.  The local and global effects of Amazon deforestation , 2001 .