In hydrology, moisture recycling or precipitation recycling refer to the process by which a portion of the precipitated water that evapotranspired from a given area contributes to the precipitation over the same area. Moisture recycling is thus a component of the hydrologic cycle. The ratio of the locally derived precipitation () to total precipitation () is known as the recycling ratio, : .[1]
The recycling ratio is a diagnostic measure of the potential for interactions between land surface hydrology and regional climate.[2][3][4][5] Land use changes, such as deforestation or agricultural intensification, have the potential to change the amount of precipitation that falls in a region. The recycling ratio for the entire world is one, and for a single point is zero. Estimates for the recycling ratio for the Amazon basin range from 24% to 56%, and for the Mississippi basin from 21% to 24%.[6]
The concept of moisture recycling has been integrated into the concept of the precipitationshed. A precipitationshed is the upwind ocean and land surface that contributes evaporation to a given, downwind location's precipitation. In much the same way that a watershed is defined by a topographically explicit area that provides surface runoff, the precipitationshed is a statistically defined area within which evaporation, traveling via moisture recycling, provides precipitation for a specific point.
See also
- Water cycle
- Precipitationshed
- Land surface effects on climate
- Al Baydha Project
References
- ^ Eltahir, E.A. "Precipitation Recycling in the Amazon Basin" (PDF). Massachusetts Institute of Technology, USA.
- ^ Koster, R.; Jouzel, J.; Suozzo, R.; Russell, G.; Broecker, W.; Rind, D.; Eagleson, P. (February 1986). "Global sources of local precipitation as determined by the Nasa/Giss GCM". Geophysical Research Letters. 13 (2): 121–124. Bibcode:1986GeoRL..13..121K. doi:10.1029/GL013i002p00121.
- ^ Trenberth, Kevin E. (May 1999). "Atmospheric Moisture Recycling: Role of Advection and Local Evaporation". Journal of Climate. 12 (5): 1368–1381. Bibcode:1999JCli...12.1368T. doi:10.1175/1520-0442(1999)012<1368:amrroa>2.0.co;2.
- ^ Brubaker, Kaye L.; Entekhabi, Dara; Eagleson, P. S. (June 1993). "Estimation of Continental Precipitation Recycling". Journal of Climate. 6 (6): 1077–1089. Bibcode:1993JCli....6.1077B. doi:10.1175/1520-0442(1993)006<1077:eocpr>2.0.co;2.
- ^ van der Ent, Rudi J.; Savenije, Hubert H. G.; Schaefli, Bettina; Steele-Dunne, Susan C. (1 September 2010). "Origin and fate of atmospheric moisture over continents". Water Resources Research. 46 (9): W09525. Bibcode:2010WRR....46.9525V. doi:10.1029/2010WR009127. ISSN 1944-7973.
- ^ Moisture recycling Archived January 16, 2006, at the Wayback Machine