Theoretical Impact of Changing Albedo on Precipitation at the Southernmost Boundary of the ITCZ in South America

Earth Interactions

Christopher E.Doughty¹ 

关键词: Albedo;    Surface roughness;    Amazon;    ITCZ;    South America;   

DOI  :  10.1175/2012EI422.1

学科分类：地球科学(综合)

来源: American Geophysical Union

【 摘 要 】

AbstractSouth America has undergone a large increase in albedo over the past decade as forests have been converted to crops and wetlands have been drained. Recent modeling literature and paleoclimate precipitation proxies have highlighted how changes in surface energy balance could affect the position of the intertropical convergence zone (ITCZ) in South America. Here, the authors investigate whether large continental increases in albedo in South America can likewise affect the southward migration of the ITCZ into South America using the NCAR Community Atmosphere Model, version 3.0 (CAM3.0) coupled with the Community Land Model, version 3.5 (CLM3.5) and a slab ocean model. Moderate Resolution Imaging Spectroradiometer (MODIS) albedo data show that between 2001 and 2008 average albedo increased by 0.0025 albedo units across all South America and by 0.0032 albedo units between 0° and 24° latitude in South America and, because of this effect, the authors’ simulations estimate an average ~23 mm yr−1 decrease ...

【 授权许可】

Unknown