High-resolution measurements from the airborne Atmospheric Nitrogen Dioxide Imager (ANDI)

Abstract

Abstract. Nitrogen dioxide is both a primary pollutant with direct health effects and a key precursor of the secondary pollutant ozone. This paper reports on the development, characterisation and test flight of the Atmospheric Nitrogen Dioxide Imager (ANDI) remote sensing system. The ANDI system includes an imaging UV/Vis grating spectrometer able to capture scattered sunlight spectra for the determination of tropospheric nitrogen dioxide (NO 2 ) concentrations by way of DOAS slant column density and vertical column density measurements.Results are shown for an ANDI test flight over Leicester City in the UK on a cloud-free winter day in February 2013. Retrieved NO 2 columns gridded to a surface resolution of 80 m × 20 m revealed hotspots in a series of locations around Leicester City, including road junctions, the train station, major car parks, areas of heavy industry, a nearby airport (East Midlands) and a power station (Ratcliffe-on-Soar). In the city centre the dominant source of NO 2 emissions was identified as road traffic, contributing to a background concentration as well as producing localised hotspots. Quantitative analysis revealed a significant urban increment over the city centre which increased throughout the flight.

Nitrogen dioxide observations from the Geostationary Trace gas and Aerosol Sensor Optimization (GeoTASO) airborne instrument: Retrieval algorithm and measurements during DISCOVER-AQ Texas 2013

“…These types of measurements from aircraft are relatively new, with push broom NO 2 airborne 2-D measurements reported recently over the Highveld region of South Africa (Heue et al, 2008), Zurich, Switzerland (Popp et al, 2012), northwest Germany (Schönhardt et al, 2015) and Leicester, United Kingdom (Lawrence et al, 2015). General et al (2014) have also recently reported airborne 2-D observations of volcanic BrO and SO 2 over Mt.…”

“…Uncertainties in surface reflectivity, the vertical distribution of aerosols relative to NO 2 and trace gas vertical profiles generally dominate air mass factor uncertainties for cloud-free NO 2 data. Lawrence et al (2015) estimated an AMF uncertainty of ∼ 8 % in remotely sensed NO 2 from an airborne mission over Leicester, United Kingdom, primarily resulting from uncertainties in the surface albedo and NO 2 profile shape.…”

High-resolution mapping of the NO<sub>2</sub> spatial distribution over Belgian urban areas based on airborne APEX remote sensing

“…Only a few recent studies report on the high-resolution 2-D spatial mapping of the NO 2 horizontal distribution from an airborne platform. The discussed hyperspectral imaging systems are based on a whiskbroom Liu et al, 2015) or pushbroom set-up (Heue et al, 2008;Popp et al, 2012;General et al, 2014;Lawrence et al, 2015;Schönhardt et al, 2015;Meier et al, 2016;Nowlan et al, 2016).…”

High-resolution airborne imaging DOAS measurements of NO<sub>2</sub> above Bucharest during AROMAT

“…Etna, Italy. Urban NO 2 distributions were measured by Popp et al (2012) above the city of Zürich, Switzerland, and by Lawrence et al (2015) above the city of Leicester, England.…”