skip to main content

DOE PAGESDOE PAGES

Title: Multi-decadal trends in global terrestrial evapotranspiration and its components

In this study, evapotranspiration (ET) is the process by which liquid water becomes water vapor and energetically this accounts for much of incoming solar radiation. If this ET did not occur temperatures would be higher, so understanding ET trends is crucial to predict future temperatures. Recent studies have reported prolonged declines in ET in recent decades, although these declines may relate to climate variability. Here, we used a well-validated diagnostic model to estimate daily ET during 1981–2012, and its three components: transpiration from vegetation (Et), direct evaporation from the soil (Es) and vaporization of intercepted rainfall from vegetation (Ei). During this period, ET over land has increased significantly (p < 0.01), caused by increases in Et and Ei, which are partially counteracted by Es decreasing. These contrasting trends are primarily driven by increases in vegetation leaf area index, dominated by greening. The overall increase in Et over land is about twofold of the decrease in Es. These opposing trends are not simulated by most Coupled Model Intercomparison Project phase 5 (CMIP5) models, and highlight the importance of realistically representing vegetation changes in earth system models for predicting future changes in the energy and water cycle.
Authors:
 [1] ;  [1] ;  [2] ;  [1] ;  [1] ;  [3] ;  [4] ;  [1] ;  [4] ;  [5] ;  [6] ;  [7]
  1. CSIRO Land and Water, Canberra (Australia)
  2. CSIRO Land and Water, Canberra (Australia); Univ. of New South Wales, Sydney, NSW (Australia)
  3. Chinese Academy of Sciences, Beijing (China)
  4. CSIRO Ocean and Atmosphere, Victoria (Australia)
  5. Univ. of New South Wales, Sydney, NSW (Australia)
  6. VU Univ. Amsterdam (The Netherlands); Ghent Univ., Ghent (Belgium)
  7. Princeton Univ., Princeton, NJ (United States)
Publication Date:
OSTI Identifier:
1238787
Grant/Contract Number:
FG02-04ER63917
Type:
Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 6; Journal ID: ISSN 2045-2322
Publisher:
Nature Publishing Group
Research Org:
Princeton Univ., Princeton, NJ (United States)
Sponsoring Org:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
Country of Publication:
United States
Language:
English
Subject:
climate change; hydrology