Evapotranspiration Trends Over the Eastern United States During the 20th Century

Hydrology

Ryan J. Kramer⁵  Lahouari Bounoua⁶  Ping Zhang⁶  Robert E. Wolfe⁴  Thomas G. Huntington³  Marc L. Imhoff¹  Kurtis Thome⁶  Genevieve L. Noyce² 

[1] Joint Global Change Research Institute, Pacific Northwest National Laboratory, 2825 University Research Court, Suite 1200, College Park, MD 20740, USA; E-Mail:;Department of Geography, University of Toronto, 100 St. George Street, Toronto, ON M5S 3G3, Canada; E-Mail:;Maine Water Science Center, U.S. Geological Survey, 196 Whitten Road, Augusta, ME 04330, USA; E-Mail:;Terrestrial Information Systems Research, Code 619, NASA Goddard Space Flight Center, NASA Goddard Space Flight Center, Code 619, Greenbelt, MD 20771, USA; E-Mail:;Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, USA;Biospheric Sciences Laboratory, Code 618, NASA Goddard Space Flight Center, NASA Goddard Space Flight Center, Code 618, Greenbelt, MD 20771, USA; E-Mails:

关键词: evapotranspiration;    vegetation greening;    vegetation feedback;   

DOI  :  10.3390/hydrology2020093

来源: mdpi

【 摘 要 】

Most models evaluated by the Intergovernmental Panel for Climate change estimate projected increases in temperature and precipitation with rising atmospheric CO₂ levels. Researchers have suggested that increases in CO₂ and associated increases in temperature and precipitation may stimulate vegetation growth and increase evapotranspiration (ET), which acts as a cooling mechanism, and on a global scale, may slow the climate-warming trend. This hypothesis has been modeled under increased CO₂ conditions with models of different vegetation-climate dynamics. The significance of this vegetation negative feedback, however, has varied between models. Here we conduct a century-scale observational analysis of the Eastern US water balance to determine historical evapotranspiration trends and whether vegetation greening has affected these trends. We show that precipitation has increased significantly over the twentieth century while runoff has not. We also show that ET has increased and vegetation growth is partially responsible.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.