WRF-Chem numerical analysis of YAK-AEROSIB aircraft data with BC emissions from Russian oil/gas flarings evaluated by satellite data
Résumé
Arctic air pollution originates mainly from long-range transport of short-lived climate forcers (SLCFs), including black carbon
(BC), ozone, and their precursors, from mid-latitudes and, also from important local anthropogenic emissions from activities such
as resource extraction, shipping and domestic combustion. Russia’s location closer to the Arctic leads to more significant
contributions from local anthropogenic emissions to levels of Arctic air pollution, especially BC from oil/gas extraction activities.
However, large uncertainties exist about the magnitude and temporal/spatial variations of BC emissions and their contribution to
Arctic BC loading. In this study, we focus on a better understanding of BC emissions from gas flaring hot spots in the Yamal-
Nenets regions of northern Russia by using WRF-Chem simulations with improved BC emissions estimated from radiometer
scanning night-light imaging from satellite data. For this study, we convert VIIRS (Visible Infrared Imaging Radiometer Suite)
12-hourly heat radiances (Elvidge et al. 2016) from Russian gas/oil flaring hot spots into daily BC emission, by using correlations
with 0.025 degree annual BC emissions derived from Sea and Land Surface Temperature Radiometer (SLSTR) GFlaringS3 data
(Caseiro et al. 2020). We analyze the origins of polluted air masses sampled during French (CNRS)-Russian YAK-AEROSIB
flights over the Ob Valley, Yamal and Kara Sea regions during October 2014 using BC tracers run in WRF-Chem. Full
chemistry-aerosol simulations of WRF-Chem, run with SAPRC-MOSAIC and ECLIPSE-v6b anthropogenic emissions, are used
to examine the sensitivity of simulated BC to gas flaring emissions. BC emissions from the flaring sector are replaced with
emissions derived from VIIRS data. Sensitivity runs with daily varying and annual average BC are also performed to examine the
impacts of temporal variations in flaring activities on Arctic BC