Multi-satellite nitrogen dioxide data record (1995-present): An effort to unify data from ultraviolet-visible spectrometers

Abstract:

Satellite observations of nitrogen dioxide (NO₂) have been crucial in our understanding of the sources, distribution, strength, and trends of nitrogen oxides (NO_x), which play a critical role in atmospheric chemistry. Satellite NO₂ observations made over the past 20+ years by multiple instruments are difficult to analyze together in a systematic way due to algorithmic, instrumental, and observational differences. There is thus a need for developing unbiased, consistent intra- and inter-mission NO₂ data records, as they together provide a continuous, decades-long record and also lay a foundation for ongoing and upcoming missions from both low earth orbit and geostationary satellites. As part of the NASA's Making Earth System Data Records for Use in Research Environments (MEaSUREs) program, this project entitled “Multi-Decadal Nitrogen Dioxide and Derived Products from Satellites (MINDS)” is developing consistent long-term global trend-quality data records of stratospheric and tropospheric NO₂ columns by applying state-of-the-art NO₂ algorithms developed for the Ozone Monitoring Instrument (OMI) to similar satellite ultraviolet-visible spectrometers that observe at different times of day. Recently added features of the algorithm include the use of (1) a new daily and field-of-view specific geometry dependent surface Lambertian Equivalent Reflectivity (GLER) product in both NO₂ and prerequisite cloud retrievals; (2) improved cloud parameters that are retrieved consistently with NO₂; (3) high resolution inputs, including a priori NO₂ profiles from a global GMI-Replay simulation at a resolution of 0.25º latitude x 0.25º longitude; and (4) improved treatment over snow/ice surfaces. In this presentation, we will provide an overview of the algorithm and discuss new NO₂ data products and their assessment from OMI and other instruments.