Stratospheric water vapor feedback.
نویسندگان
چکیده
We show here that stratospheric water vapor variations play an important role in the evolution of our climate. This comes from analysis of observations showing that stratospheric water vapor increases with tropospheric temperature, implying the existence of a stratospheric water vapor feedback. We estimate the strength of this feedback in a chemistry-climate model to be +0.3 W/(m(2)⋅K), which would be a significant contributor to the overall climate sensitivity. One-third of this feedback comes from increases in water vapor entering the stratosphere through the tropical tropopause layer, with the rest coming from increases in water vapor entering through the extratropical tropopause.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 110 45 شماره
صفحات -
تاریخ انتشار 2013