Global Cooling After the Eruption of Mount Pinatubo: A Test of Climate Feedback by Water Vapor
Brian J. Soden,1*
Richard T. Wetherald,1
Georgiy L. Stenchikov,2
Alan Robock2
The sensitivity of Earth's climate to an external radiative
forcing depends critically on the response of water vapor. We use the
global cooling and drying of the atmosphere that was observed after the
eruption of Mount Pinatubo to test model predictions of the climate
feedback from water vapor. Here, we first highlight the success of the
model in reproducing the observed drying after the volcanic eruption.
Then, by comparing model simulations with and without water vapor
feedback, we demonstrate the importance of the atmospheric drying in
amplifying the temperature change and show that, without the strong
positive feedback from water vapor, the model is unable to reproduce
the observed cooling. These results provide quantitative evidence of
the reliability of water vapor feedback in current climate models,
which is crucial to their use for global warming projections.
1 Geophysical Fluid Dynamics
Laboratory/National Oceanic and Atmospheric Administration, Princeton
University, Princeton, NJ 08542, USA.
2 Department
of Environmental Sciences, Rutgers University, New Brunswick, NJ 08901, USA.
*
To whom correspondence should be addressed. E-mail:
bjs{at}gfdl.gov
