HR: 12:05h
AN: GC12A-08    [Abstracts]
TI: Changes in Global Water Cycle: Discrepancy Between Satellite Observations and Climate Models
AU: Wentz, F J
EM: frank.wentz@remss.com
AF: Remote Sensing Systems, 438 First St., Suite 200, Santa Rosa, CA 95401, United States
AU: * Ricciardulli, L
EM: ricciardulli@remss.com
AF: Remote Sensing Systems, 438 First St., Suite 200, Santa Rosa, CA 95401, United States
AU: Hilburn, K
EM: hilburn@remss.com
AF: Remote Sensing Systems, 438 First St., Suite 200, Santa Rosa, CA 95401, United States
AB: Most of the attention on climate change research has been devoted to understanding and predicting surface and atmospheric temperature changes. Changes in the global hydrologic cycle play an important role in impacting the society but they are less understood. The availability of 20 years of a continuous and carefully calibrated satellite data record from the Special Sensor Microwave Imager (SSM/I) provides us with the opportunity to study global changes of variables related to the water cycle: precipitation (P), water vapor (WV), surface winds (U) and derived evaporation (E). The satellite data show that for the past two decades WV, P and E have all changed at the same rate, about 6.5% per degree of warming. This rate of change is expected for water vapor, as dictated by the Clausius Clapeyron equation (C-C), and is also predicted by climate simulations. On the other hand, global P and E are not constrained by C-C, but rather by the atmospheric energy budget. Climate models predict a muted response of the water cycle to global warming, with a P and E increase on the order of 2%/C. This discrepancy between observed and modeled changes to the water cycle needs to be resolved if we want to have confidence in the models and in the observed data record.
DE: 1626 Global climate models (3337, 4928)
DE: 1630 Impacts of global change (1225)
DE: 1640 Remote sensing (1855)
DE: 1655 Water cycles (1836)
DE: 3354 Precipitation (1854)
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting