Andrew E Dessler
Texas A&M University
Dept. of Atmospheric Sciences
College Station, TX 77843-3150

E-mail: adessler@tamu.edu
Phone: 979-862-1427
Fax:

We propose to use CALIPSO and CloudSAT measurements of clouds, combined with other A-train measurements of temperature, humidity, and trace chemical constituents, to answer key questions about our climate system. We will focus on two questions:

• What mechanism(s) control the distribution of thin, near tropopause cirrus in the tropics? What is the impact of these clouds on the abundance of water vapor in the stratosphere?
  It has been suggested that thin, near tropopause cirrus (TNTC) in the tropics can affect our global climate in several important ways. They are thought to play a role in regulating stratospheric water vapor, which has an important role in regulating our climate. In addition, TNTC are themselves radiatively important. Despite the potential importance of these clouds, however, our knowledge of their distribution and formation mechanisms is poor. We propose to study these tropical TNTC in order to advance our understanding of these important clouds.
• What is distribution of stratosphere-penetrating extratropical convection? How does this convection affect the chemical composition of the extratropical lower stratosphere?
  It is now well known that mid-latitude convection can penetrate well above the tropopause, and in the process perturb the chemical composition of the lower stratosphere, in particular the abundance water vapor. However, our understanding of how often and where this occurs, how high the convection extends, and the detailed impact on the constituent budget is poorly known. We propose to study tropopause-penetrating extratropical convection in order to advance our understanding of this process.

Finally, to aid our own research as well as help improve the CALIPSO data, we propose here to join that science team.