Origin of elemental carbon in snow from western Siberia and northwestern European Russia during winter–spring 2014, 2015 and 2016

Abstract

Abstract. Short-lived climate forcers have been proven important both for the climate and human health. In particular, black carbon (BC) is an important climate forcer both as an aerosol and when deposited on snow and ice surface because of its strong light absorption. This paper presents measurements of elemental carbon (EC; a measurement-based definition of BC) in snow collected from western Siberia and northwestern European Russia during 2014, 2015 and 2016. The Russian Arctic is of great interest to the scientific community due to the large uncertainty of emission sources there. We have determined the major contributing sources of BC in snow in western Siberia and northwestern European Russia using a Lagrangian atmospheric transport model. For the first time, we use a recently developed feature that calculates deposition in backward (so-called retroplume) simulations allowing estimation of the specific locations of sources that contribute to the deposited mass. EC concentrations in snow from western Siberia and northwestern European Russia were highly variable depending on the sampling location. Modelled BC and measured EC were moderately correlated (R=0.53–0.83) and a systematic region-specific model underestimation was found. The model underestimated observations by 42 % (RMSE = 49 ng g−1) in 2014, 48 % (RMSE = 37 ng g−1) in 2015 and 27 % (RMSE = 43 ng g−1) in 2016. For EC sampled in northwestern European Russia the underestimation by the model was smaller (fractional bias, FB > −100 %). In this region, the major sources were transportation activities and domestic combustion in Finland. When sampling shifted to western Siberia, the model underestimation was more significant (FB < −100 %). There, the sources included emissions from gas flaring as a major contributor to snow BC. The accuracy of the model calculations was also evaluated using two independent datasets of BC measurements in snow covering the entire Arctic. The model underestimated BC concentrations in snow especially for samples collected in springtime.

Estimation of black carbon emissions from Siberian fires using satellite observations of absorption and extinction optical depths

“…As a significant BC source, BB plays an especially important role in climate processes in the Arctic, where the increase of the annual surface temperature in the period since 1875 has been almost twice as large as that in the rest of the Northern Hemisphere (Bekryaev et al, 2010). Several studies (e.g., Shindell and Faluvegi, 2009;Flanner, 2013;Sand et al, 2015) have indicated that a significant part (up to about 50 %) of this temperature increase could have been induced by BC. There is an abundant amount of evidence that BB provides a significant contribution to BC in the Arctic atmosphere in the spring and summer (e.g., Stohl, 2006;Stohl et al, 2006;Warneke et al, 2010;Bian et al, 2013;Hall and Loboda, 2017;Popovicheva et al, 2017;Winiger et al, 2017;Qi et al, 2017;Xu et al, 2017;Evangeliou et al, 2018).…”

“…It has also been estimated that Siberian fires alone contributed almost half (46 %) of the total BC amount deposited in the Arctic over a period of 12 years (2002-2013). Radiative effects associated with BC residing in the Arctic atmosphere include both direct radiation budget changes causing strong warming of the Arctic surface and significant changes in atmospheric stability and cloud cover (Flanner, 2013;Sand et al, 2015). Significant increases in surface temperature in the Arctic as a result of perturbations of the meridional transport can even be caused by BC residing in the midlatitude atmosphere (Sand et al, 2015).…”

Atmospheric Transport, a Major Pathway of Microplastics to Remote Regions

“…3). For comparison, note that these values are almost three orders of magnitude lower than those of black carbon in Arctic snow 43,44 . It is seen that Northern Europe (e.g., Scandinavia), on one side, and North America on the other present higher snow concentrations than the Arctic.…”

Top-down estimates of black carbon emissions at high latitudes using an atmospheric transport model and a Bayesian inversion framework

“…Land cover classification of burned areas are taken from the MODIS land cover change product (MOD12) (Friedl et al, 2010). This dataset is considered to be more realistic than GFED4 due to the emission factors used for BC (May et al, 2014) and the different approach to burned area calculation (see Hao et al, 2016).…”