Ozone transport from stratosphere-to-troposphere occurs in midlatitude synoptic weather systems, but accurately estimating the transport is a difficult and long-standing problem. Jaeglé et al.  look at cross-tropopause ozone transport associated with extratropical cyclones and dry intrusions, using a long record of satellite data, meteorological reanalyses, and chemical transport model results. Their results quantify the circulation and transport influences of cyclonic ‘dry intrusions’ and ‘warm conveyor belts,’ and provide new estimates of their seasonal influence on tropospheric ozone. These new results complement findings from many other studies, and this work makes a welcome contribution to evaluating reanalysis data sets and quantifying extratropical ozone transport.
Citation: Jaeglé, L., Wood, R., & Wargan, K. . Multiyear composite view of ozone enhancements and stratosphere-to-troposphere transport in dry intrusions of northern hemisphere extratropical cyclones. Journal of Geophysical Research: Atmospheres, 122. https://doi.org/10.1002/2017JD027656
—William Randel, Editor, JGR: Atmospheres