Dr. Joanne Hall (Post-Doctoral Research Associate) and Dr. Tatiana Loboda (Associate Professor) published a paper in the Northern Eurasian Earth Science Partnership Initiative (NEESPI) Special Issue in Environmental Research Letters. A summary of the research findings can be found below.
Hall, J. V., & Loboda, T. V. (2018). Quantifying the variability of potential black carbon transport from cropland burning in Russia driven by atmospheric blocking events. Environmental Research Letters.
The deposition of short-lived aerosols and pollutants on snow above the Arctic Circle transported from northern mid-latitudes have amplified the short term warming in the Arctic region. Specifically, black carbon has received a great deal of attention due to its absorptive efficiency and its fairly complex influence on the climate. Cropland burning in Russia is a large contributor to the black carbon emissions deposited directly onto the snow in the Arctic region during the spring when the impact on the snow/ice albedo is at its highest. In this study, our focus is on identifying a possible atmospheric pattern that may enhance the transport of black carbon emissions from cropland burning in Russia to the snow-covered Arctic. Specifically, atmospheric blocking events are large-scale patterns in the atmospheric pressure field that are nearly stationary and act to block migratory cyclones. The persistent low-level wind patterns associated with these mid-latitude weather patterns are likely to accelerate potential transport and increase the success of transport of black carbon emissions to the snow-covered Arctic during the spring.
Our results revealed that overall, in March, the transport time of hypothetical black carbon emissions from Russian cropland burning to the Arctic snow is shorter (in some areas over 50 hours less at higher injection heights) and the success rate is also much higher (in some areas up to 100% more successful) during atmospheric blocking conditions as compared to conditions without an atmospheric blocking event (Figure 1 – subset of larger figure).
Figure 1: 900 mb March 2003–2015: The average transport time (hours) difference maps between blocked and nonblocked conditions. The difference map color bars have been created so that red grid cells indicate transport under blocked conditions was quicker compared to the blue color indicating that transport was under nonblocked conditions.
Figure 2 highlights the transport trajectories associated with an atmospheric blocking event in April 2006.
Figure 2: 900 mb April 2006 blocking event transport time to the snow-covered Arctic within 96 hours of burning (a) and corresponding trajectories (b). A subset of successful trajectories (c) is shown over European Russia to highlight the anticyclonic winds associated with the April 2006 blocking event.
The enhanced transport of black carbon has important implications for the efficacy of deposited black carbon. Therefore, understanding these relationships could lead to possible mitigation strategies for reducing the impact of deposition of black carbon from crop residue burning in the Arctic.