TROPOMI/S5P MLS/BASCOE tropospheric ozone product and TROPOMI observation of ozone precursors

Sentinel 5 Precursor (S5P) satellite was launched into a polar orbit in October 2017, carrying the TROPOMI instrument. S5P has sun synchronous orbit with an equator crossing time of 13:30 LT; TROPOMI achieves an almost daily coverage, due to the wide swath width of 2600 km. Based on the observed spectra in the UV-Vis range the trace gases ozone, formaldehyde and nitrogen dioxide are retrieved. We developed a research tropospheric ozone product based on the operational total column from S5P and the stratospheric column obtained from Aura MLS assimilated ozone profiles using the BASCOE system. The enhanced tropospheric ozone columns are observed at several places and often collocate with locale enhancements of NO₂ and HCHO. Both these trace gases are known to be involved in the tropospheric ozone formation.

The tropospheric ozone product will be briefly presented; the focus will be on large scale enhancements of tropospheric ozone and collocated HCHO and NO₂ observations. In addition examples of enhancemnets of HONO or Glyoxal may be stduied. The large fires in the Amazonian forest and Australia cause an enhancement compared to previous years. Over the southern US both HCHO and tropospheric ozone are enhanced in summer time. Some transport of ozone and its’ precursors can be found in East Asia.