Title: "Recent source variability of two ozone depleting greenhouse gases: N2O and HCFC-22"

Abstract: N2O and HCFC-22 (CHClF2) are both important greenhouse gases as well as ozone depleting substances, and yet there is still a limited understanding of the magnitude, variability and partitioning of their sources. In this talk, I will examine the emissions of these species, using measurements from the Advanced Global Atmospheric Gases Experiment (AGAGE) network and a three-dimensional chemical transport model.
For N2O, I will use these observations to explore the drivers of inter-annual variability between 1995 and 2009. The contribution of variations in emissions from soil, biomass burning and anthropogenic sources will be investigated, with particular emphasis on the influence of climate on soil flux.
HCFC-22, used mainly in refrigeration and air conditioning, is regulated under the Montreal Protocol. The protocol requires the phase out of these gases only from developed countries at present. I will use data from AGAGE and the National Oceanic and Atmospheric Administration (NOAA) to critically examine the ability of these networks to verify the success of such an international treaty, by distinguishing between emissions from developed and developing regions.

Speaker's website: http://globalchange.mit.edu/people/staff.php?id=253