Water vapor and ozone in the troposphere and stratosphere over Costa Rica and Galapagos during TC4
Abstract
Intensive observations of water vapor and ozone were taken during the Tropical Composition, Cloud and Climate Coupling (TC4) campaign using balloon borne sensors at San Jose, Costa Rica and at San Cristobal, Galapagos, Ecuador. Water vapor profiles between the surface and the middle stratosphere were measured using Cryogenic Frostpoint Hygrometers (CFH) while ozone profiles were measured using ECC ozone sondes as part of the same payload. Five night time soundings at Costa Rica also carried the Fluorescent Advanced Stratospheric Hygrometer for Balloon (FLASH-B). Ozone profiles indicate that convection over Costa Rica on average reaches about 13 km but ozone remains low compared to Galapagos up to 17.6 km. Water vapor profiles on the other hand show large regional differences up to 14.5 km. Galapagos shows slightly colder tropopause temperatures and slightly higher supersaturation values at the cold point compared to Costa Rica. Dehydration at the cold point appears to be controlled by large scale and stratospheric processes, not by convective processes over Central America. The middle troposphere is significantly drier at Galapagos, although individual layers show relative humidity values larger than those at Costa Rica at similar altitudes. Instrument intercomparisons between FLASH-B and CFH show good agreement in the TTL and cannot explain differences with aircraft sensors which have been previously observed.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2007
- Bibcode:
- 2007AGUFM.A22A..04V
- Keywords:
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- 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0322 Constituent sources and sinks;
- 0340 Middle atmosphere: composition and chemistry;
- 0365 Troposphere: composition and chemistry;
- 0368 Troposphere: constituent transport and chemistry