Man-made halocarbons have had a significant impact on the destruction of stratospheric ozone and radiative heating of the atmosphere. We measure halocarbons and other gases throughout the global atmosphere on an ongoing basis. This data provides unique insights into global atmospheric processes and also provides data relevant for assessing the effectiveness of international Protocols such as the Montreal Protocol on Substances that Deplete the Ozone Layer, and the Kyoto Protocol to the UN Framework Convention on Climate Change. This data allows us to address policy-relevant questions such as (1) Has the Montreal Protocol been amended and revised sufficiently to save the ozone layer? (2) When will the ozone layer recover? (3) Does the Montreal Protocol have a beneficial effect on climate? (4) Are the replacements for the main ozone depleting gases adversely affecting climate? (5) What is causing continued increases in trace gases in the atmosphere? (6) Why are some trace gases now decreasing? (7) How have emissions of ozone-depleting gases, their replacements, and other trace gases changed over recent years? (8) What factors will influence their future concentrations?

The data also allows us to address scientific questions such as(1) Is the atmosphere's ability to cleanse itself of pollutants fairly stable from year-to-year or is it highly sensitive to pollutant emissions and variations in natural processes? (2) What processes influence the emission rates from natural processes of compounds affecting climate and the ozone layer? (3) Can carbonyl sulfide provide an accurate metric of photosynthesis on broad scales and its sensitivity to changes in the terrestrial environment? (4) How does one reliably and accurately infer trace gas emissions on a regional or nation scale with daily surface measurements at a network of surface sites and weekly measurements from ongoing vertical profile measurements through North America?

These questions are being addressed with our highly precise and accurate measurements of over 25 halocarbons, hydrocarbons, and sulfur-containing compounds from a suite of three sampling networks: approximately 15 remote background sites across the globe, a suite of approximately seven tall towers across North America, and a network of over 12 aircraft profiling locations across North America. We are looking for interested applicants to investigate new sample analysis techniques; provide tools for more effective sample analysis and data processing; and to interpret data addressing the questions outlined above with inverse modeling, correlation analysis, and other mathematical techniques.

 

key words

Global atmospheric chemistry; Montreal Protocol; Ozone depletion; Kyoto Protocol; Climate change; Polar regions and processes; Ozonosphere; Stratosphere; Chlorofluorocarbons; Chlorofluorohydrocarbons; Hydrofluorocarbons; carbon cycle; Carbonyl Sulfide

Citizenship:  Open to U.S. citizens, permanent residents and non-U.S. citizens

Level:  Open to Postdoctoral and Senior applicants