Marianna Linz, MIT/WHOI. ‘A theory for calculating the strength of the stratospheric circulation from age’. Clark 507

February 28, 2017 @ 3:05 pm – 4:05 pm
Clark 507

The Brewer-Dobson circulation, the meridional overturning of mass in the stratosphere, is important for the distribution of gases in the stratosphere, such as ozone and water vapor, which impact surface climate. I will present a theory that relates the ideal tracer “age of air” to this circulation strength. Age can be determined from certain trace gases, and I have applied the theory to obtain the first data-based estimate of the global meridional overturning circulation of the stratosphere. When I compare this to models and reanalysis data, I find substantial disagreement. I will then show how age of air provides enough information to determine the full circulation by deriving a quantitative relationship between the age distribution and the adiabatic component of the circulation.