Ozone Anomalies in Dry Intrusions Associated with Atmospheric Rivers
Abstract
As a result of their important role in weather and the global hydrological cycle, understanding atmospheric rivers' (ARs) connection to synoptic-scale climate patterns and atmospheric dynamics has become increasingly important. The discovery of anomalous upper tropospheric ozone associated with an extreme AR event using Ozone Monitoring Instrument data inspired deeper investigation. In addition to case studies of two extreme AR events, we produce a December climatology of the three-dimensional structure of water vapor and ozone distributions associated with ARs in the northeastern Pacific from 2004-2014 using MERRA-2 reanalysis data products. Results show that positive ozone anomalies reside in the dry intrusions of stratospheric air due to stratosphere to troposphere transport (STT) behind the intense water vapor transport of the AR. We find a correlation between AR strength and excess ozone concentration, and we quantify the ozone flux due to the likely irreversible mixing of stratospheric ozone in the troposphere. This study identifies STT of ozone in connection with ARs for the first time, and improves estimates of tropospheric ozone concentration due to STT. In light of predictions that ARs will become more intense and/or frequent with climate change, the quantification of STT ozone flux in connection with ARs is especially valuable for future radiative forcing calculations.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFM.A52C..01H