Intimately tracking NO pollution over the New York City - Long Island Sound land-water continuum: An integration of shipboard, airborne, satellite observations, and models.

Nitrogen dioxide (NO) pollution remains a serious global problem, particularly near highly populated urbanized coasts that face increasing challenges with climate change. Yet, the combined impact of urban emissions, pollution transport, and complex meteorology on the spatiotemporal dynamics of NO along heterogeneous urban coastlines remains poorly characterized. Here, we integrated measurements from different platforms - boats, ground-based networks, aircraft, and satellites - to characterize total column NO (TCNO) dynamics across the land-water continuum in the New York metropolitan area, the most populous area in the United States that often experiences the highest national NO levels.

Volatile chemical product emissions enhance ozone and modulate urban chemistry.

Decades of air quality improvements have substantially reduced the motor vehicle emissions of volatile organic compounds (VOCs). Today, volatile chemical products (VCPs) are responsible for half of the petrochemical VOCs emitted in major urban areas. We show that VCP emissions are ubiquitous in US and European cities and scale with population density.

Evaluating the impact of spatial resolution on tropospheric NO column comparisons within urban areas using high-resolution airborne data.

NASA deployed the GeoTASO airborne UV-Visible spectrometer in May-June 2017 to produce high resolution (approximately 250 × 250 m) gapless NO datasets over the western shore of Lake Michigan and over the Los Angeles Basin. The results collected show that the airborne tropospheric vertical column retrievals compare well with ground-based Pandora spectrometer column NO observations (r=0.91 and slope of 1.

Comparison of Near-surface NO Pollution with Pandora Total Column NO during the Korea-United States Ocean Color (KORUS OC) Campaign.

Near-surface air quality (AQ) observations over coastal waters are scarce, a situation that limits our capacity to monitor pollution events at land-water interfaces. Satellite measurements of total column (TC) nitrogen dioxide (NO) observations are a useful proxy for combustion sources but the once daily snapshots available from most sensors are insufficient for tracking the diurnal evolution and transport of pollution. Ground-based remote sensors like the Pandora Spectrometer Instrument (PSI) that have been developed to verify space-based total column NO and other trace gases are being tested for routine use as certified AQ monitors.