Characterization of the Synoptic and Mesoscale Meteorological Conditions during the OWLETS and OWLETS-2 Field Campaigns

Mesoscale sea/bay breeze circulations have been shown to exacerbate ozone pollution over metropolitan areas adjacent to coastlines. These mesoscale processes, which can lead to significant land-water ozone gradients, are also impacted by the prevailing synoptic meteorological conditions. At sub-pixel scales, capturing these gradients over land-water transition areas is a well-documented challenge for remote sensing instrumentation and models. In anticipation of future geostationary air quality missions (e.g. TEMPO, GEMS) and to improve air quality modeling, two field studies over the Chesapeake Bay region were carried out to better understand the variability of ozone and other trace gases spatiotemporally between the bay and adjacent land. OWLETS (2017) and OWLETS-2 (2018), the Ozone Water-Land Environmental Transition Studies, investigated the southern Chesapeake Bay and northern Chesapeake Bay regions, respectively. This study uses data from both of these field campaigns in an attempt to characterize the meteorological conditions and tropospheric ozone variability during these time periods. To contextualize the synoptic and mesoscale meteorological patterns during these campaigns, meteorological conditions will be classified using gridded reanalysis and other observational datasets. In situ air quality data will be used in conjunction with these results to put the meteorological conditions into perspective for these intensive study periods. A better understanding of the meteorological conditions affecting sub-pixel ozone variability will aid in the future analysis of geostationary air quality retrievals and help guide future analyses of data sets from these field campaigns.