Forcings in GISS Climate Model

Stratospheric H2O

The input of stratospheric H2O from the photolysis of CH4 is a significant stratospheric forcing and is tied directly to the concentration of CH4 with a ~2-year delay to account for the time taken to mix surface air to the mid-stratosphere. In CMIP3 and in non-interactive CMIP5 simulations, this is calculated using a scaling to the zonal mean pattern shown below, e.g., the annual stratospheric H2O production rate for a tropospheric CH4 based on the two-dimensional model of I. Plumb.

H2O production rate @ 1675ppb CH4

Download the production rate data:

+ ASCII text

In interactive simulations, the water vapor input is determined within the model code as a function of the concentrations, solar irradiance, humidity and temperature, and is available as a diagnostic in the CMIP5 archive.


Please address inquiries about these data to Dr. Timothy Hall.

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This page was written by Dr. Makiko Sato and Dr. Gavin Schmidt.

Data last updated: 2002-01-10 — Page last updated: 2016-11-02.

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