Highly resolved mapping of NO 2 vertical column densities from GeoTASO measurements over a megacity and industrial area during the KORUS-AQ campaign

[摘要] The Korea–United States Air Quality (KORUS-AQ) campaignis a joint study between the United States National Aeronautics and SpaceAdministration (NASA) and the South Korea National Institute ofEnvironmental Research (NIER) to monitor megacity and transboundary airpollution around the Korean Peninsula using airborne and ground-basedmeasurements. Here, tropospheric nitrogen dioxide (NO 2 ) slant columndensity (SCD) measurements were retrieved from Geostationary Trace andAerosol Sensor Optimization (GeoTASO) L1B data during the KORUS-AQ campaign(2 May to 10 June 2016). The retrieved SCDs were converted to troposphericvertical column densities using the air mass factor (AMF) obtained from aradiative transfer calculation with trace gas profiles and aerosol propertyinputs simulated with the Community Multiscale Air Quality (CMAQ) model andsurface reflectance data obtained from the Moderate Resolution ImagingSpectroradiometer (MODIS). For the first time, we examine highly resolved(250 m  ×  250 m resolution) tropospheric NO 2 over the Seoul andBusan metropolitan regions and the industrial region of Anmyeon. We revealthat the maximum NO 2 vertical column densities (VCDs) were 4.94×10 16 and 1.46×10 17  molec. cm −2 at 09:00 and 15:00 LT over Seoul,respectively, 6.86×10 16 and 4.89×10 16  molec. cm −2 in the morning and afternoon over Busan, respectively,and 1.64×10 16  molec. cm −2 over Anmyeon. The VCDsretrieved from the GeoTASO airborne instrument were correlated with thoseobtained from the Ozone Monitoring Instrument (OMI) ( r =0.48 ), NASA'sPandora Spectrometer System ( r =0.91 ), and NO 2 mixing ratiosobtained from in situ measurements ( r =0.07 in the morning, r =0.26 inthe afternoon over the Seoul, and r >0.56 over Busan). Based onour results, GeoTASO is useful for identifying NO 2 hotspots and theirspatial distribution in highly populated cities and industrial areas.

[学科分类] 内科医学