NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Observations of the Upper Tropospheric Water Vapor Feedback in UARS MLS and HALOE DataOne of the biggest uncertainties in climate science today concerns the water vapor feedback. Most GCMs hold relative humidity fixed as the climate changes, which provides a strong positive feedback to warming due from anthropogenic greenhouse gas emissions. Some in the community, on the other hand, have speculated that tropospheric specific humidity will remain fixed as the climate changes. Observational studies have attempted to resolve this disagreement, but the results have been inconclusive, and few of the studies have focused on the upper troposphere (UT). This is a significant oversight: the surface temperature is especially sensitive to changes in water vapor in the UT owing to the cold temperatures found there. We present an analysis of UARS MLS and HALOE water vapor measurements at 21 5 hPa. We find strong evidence that the water vapor feedback in the UT is positive, but not as strong as fixed relative humidity scenarios. This suggests that GCMs are overestimating the sensitivity of the climate.
Document ID
20040074236
Acquisition Source
Headquarters
Document Type
Conference Paper
Authors
Dessler, A. E.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Minschwaner, K. R.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
August 21, 2013
Publication Date
January 1, 2004
Subject Category
Meteorology And Climatology
Meeting Information
Meeting: FAll AGU 2003
Location: San Francisco, CA
Country: United States
Start Date: December 8, 2003
End Date: December 12, 2003
Sponsors: American Geophysical Union
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

Available Downloads

There are no available downloads for this record.
No Preview Available