Science Seminars

11/12/2010 – Stratospheric circulation changes and their relation to species distributions

Speaker: Karen Rosenlof (ATOC/LASP)
Date: Friday, Nov 12, 2010
Time: 4:00 PM
Location: Duane, Gamow tower

Seminar Abstract:

Results from two recent papers discussing changes in stratospheric constituents driven by changes in the circulation and some associated impacts on climate will be presented. In the first paper (Solomon et al., 2010), we show that a significant decrease in stratospheric water vapor a consequence of an increase in the mass flux into the tropical stratosphere. This change is water vapor is also shown to be radiatively significant, slowing the increase in global surface temperature over the 2000-2009 period by about 25% compared to what would have occurred due only to carbon dioxide and other greenhouse gas increases. In the second paper (Ray et al., 2010), we show how changes in the stratospheric circulation and mixing impact tracer concentrations through use of a leaky pipe model. We conclude that observed changes in constituents that give indications with age of air in the stratosphere are not inconsistent with increases in the strength of the mean meridional circulation when one takes into account possible changes in mid latitude to tropical mixing.