fresh water
; article
; El Nino
; environmental parameters
; evaporation
; geology
; ocean mass balance
; precipitation
; priority journal
; sea level rise
; sea surface temperature
英文摘要:
Freshwater discharge from the continents is a key component of Earth's water cycle that sustains human life and ecosystem health. Surprisingly, owing to a number of socioeconomic and political obstacles, a comprehensive global river discharge observing system does not yet exist. Here we use 13 years (1994-2006) of satellite precipitation, evaporation, and sea level data in an ocean mass balance to estimate freshwater discharge into the global ocean. Results indicate that global freshwater discharge averaged 36,055 km 3/y for the study period while exhibiting significant interannual variability driven primarily by El Niño Southern Oscillation cycles. The method described here can ultimately be used to estimate long-term global discharge trends as the records of sea level rise and ocean temperature lengthen. For the relatively short 13-year period studied here, global discharge increased by 540 km3/y2, which was largely attributed to an increase of globalocean evaporation (768 km3/y2). Sustained growth of these flux rates into long-term trends would provide evidence for increasing intensity of the hydrologic cycle.
Syed, T.H., Department of Earth System Science, University of California, Irvine, CA 92697-3100, United States, Department of Applied Geology, Indian School of Mines, Dhanbad 826004, India; Famiglietti, J.S., Department of Earth System Science, University of California, Irvine, CA 92697-3100, United States, UC Center for Hydrologic Modeling, University of California, Irvine, CA 92697, United States; Chambers, D.P., College of Marine Science, University of South Florida, St. Petersburg, FL 33701, United States; Willis, J.K., Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, United States; Hilburn, K., Remote Sensing Systems, Santa Rosa, CA 95401, United States
Recommended Citation:
Syed T.H.,Famiglietti J.S.,Chambers D.P.,et al. Satellite-based global-ocean mass balance estimates of interannual variability and emerging trends in continental freshwater discharge[J]. Proceedings of the National Academy of Sciences of the United States of America,2010-01-01,107(42)