Karen Shell

Karen Shell (CGD), Many different feedbacks control the reponse of the climate system to an imposed climate forcing; however, different climate models produce feedbacks of different magnitudes. To study climate feedbacks, Jeff Kiehl (NCAR, CGD division) and I have been splitting the different feedbacks into two parts: the change in the particular climate component between a doubled CO2 case and a present-day CO2 case, and the effect that a standard change in that component has on the climate (measured by the effect on the earth's radiation balance). We can then combine these two values to determine the feedback for a particular climate change experiment. This technique allows us to compare similar results from different models to determine if differences in feedbacks are due to differences in how the components respond to climate change or due to differences in how the changed components affect the climate. Christine Shields (NCAR), Brian Soden (U. Miami), and Isaac Held (GFDL) have also been working on this project.

In addition, I have continued my thesis work using a simple dust model. June Wang (Harvard) and I have been exploring ways of using satellite data in the model to constrain optical properties of aerosols.

Funding Sources

This research is supported by the National Science Foundation.