タイトル | Observations of the Upper Tropospheric Water Vapor Feedback in UARS MLS and HALOE Data |
著者(英) | Dessler, A. E.; Minschwaner, K. R. |
著者所属(英) | NASA Goddard Space Flight Center |
発行日 | 2004-01-01 |
言語 | eng |
内容記述 | One 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. |
NASA分類 | Meteorology and Climatology |
権利 | No Copyright |
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