Open AccessLand-Cover and Surface Water Change Drive Large Albedo Increases in South America*
Author(s) -
Scott R. Loarie,
David B. Lobell,
Gregory P. Asner,
Christopher B. Field
Publication year - 2011
Publication title -
earth interactions
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.309
H-Index - 38
ISSN - 1087-3562
DOI - 10.1175/2010ei342.1
Subject(s) - albedo (alchemy) , environmental science , moderate resolution imaging spectroradiometer , climate change , deforestation (computer science) , climatology , land cover , vegetation (pathology) , atmospheric sciences , magnitude (astronomy) , physical geography , geography , land use , geology , satellite , oceanography , ecology , astronomy , performance art , computer science , engineering , biology , art history , aerospace engineering , medicine , art , programming language , physics , pathology
Albedo is an important factor affecting global climate, but uncertainty in the sources and magnitudes of albedo change has led to simplistic treatments of albedo in climate models. Here, the authors examine nine years (2000–08) of historical 1-km Moderate Resolution Imaging Spectroradiometer (MODIS) albedo estimates across South America to advance understanding of the magnitude and sources of large-scale albedo changes. The authors use the magnitude of albedo change from the arc of deforestation along the southeastern edge of the Brazilian Amazon (+2.8%) as a benchmark for comparison. Large albedo increases (>+2.8%) were 2.2 times more prevalent than similar decreases throughout South America. Changes in surface water drove most large albedo changes that were not caused by vegetative cover change. Decreased surface water in the Santa Fe and Buenos Aires regions of Argentina was responsible for albedo increases exceeding that of the arc of deforestation in magnitude and extent. Although variations in the natural flooding regimes were likely the dominant mechanism driving changes in surface water, it is possible that human manipulations through dams and other agriculture infrastructure contributed. This study demonstrates the substantial role that land-cover and surface water change can play in continental-scale albedo trends and suggests ways to better incorporate these processes into global climate models.