Chemical Patterns Controlling Tropospheric Ozone and Methane: The ATom Dataset
Abstract
The Atmospheric Tomography Experiment (ATom) provides unique measurements of atmospheric composition on four meridional, profiling transects of the central Pacific and Atlantic Oceans, one in each season. These observations provide most of the key chemical constituents involved in the photochemical reactions controlling the greenhouse gases ozone and methane. Flight paths are preset to give a representative, objective sampling of air parcels in the troposphere (0.5 to 12 km) where most of the photochemical loss of ozone and methane occurs. This talk presents the statistical distributions and covariation of the key species from ATom and compares them with output from six global chemistry models. The reactivity (e.g., methane loss, ozone production and loss) of each parcel is used in these model-measurement evaluations to place emphasis on the location and composition of air parcels that matter most. Also, all four deployments (ATom 1-4) were analyzed to identify seasonal changes for reactivities. ATom analysis points to specific model failings in terms of the frequency of occurrence of these photochemically 'hot' air parcels in the remote troposphere and possibly identifies a common cause for the overestimation of methane loss in most all models as well as the distinct regions of ozone production (upper troposphere) and loss (lower troposphere).
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMA086.0007G
- Keywords:
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- 0317 Chemical kinetic and photochemical properties;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0345 Pollution: urban and regional;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 3339 Ocean/atmosphere interactions;
- ATMOSPHERIC PROCESSES;
- 3360 Remote sensing;
- ATMOSPHERIC PROCESSES