Black Carbon in the Near-Surface Atmosphere Far Away from Emission Sources: Comparison of Measurements and MERRA-2 Reanalysis Data
T. B. Zhuravleva, A. V. Artyushina, А. А. Виноградова, Yu. V. Voronina
Abstract
We compare the time variations in monthly average concentrations of black carbon in the surface air layer obtained from field measurements ([BC]) and from MERRA-2 reanalysis ([BC]M) at four monitoring sites located in the northern part of Russia (Tiksi Observatory, Pechora-Ilych Biosphere Reserve), Alaska (Barrow station), and Greenland (Summit station). It is shown that the MERRA-2 reanalysis data for the regions of Tiksi and Barrow do not completely reflect the [BC] variations during the year, in contrast to the Pechora-Ilych Biosphere Reserve, where the discrepancies are within 30–50%. The [BC]M reanalysis products for the Summit monitoring site qualitatively agree with the measurements characterizing the BC content in the free troposphere, but they underestimate [BC] by more than a factor of two. On the whole, our analysis showed that the results of the MERRA-2 reanalysis of the monthly average indices of near-surface concentration of atmospheric black carbon can be used for climate assessments for hard-to-reach northern regions in the warm season with an error of about 30%. Possible causes for the discrepancies between [BC] and [BC]M are discussed for different times of the year and observation sites.