Elemental and water-insoluble organic carbon in Svalbard snow: a synthesis of observations during 2007–2018

• Published in: Atmospheric Chemistry and Physics
• Main Authors: Zdanowicz, Christian, Gallet, Jean-Charles, Björkman, Mats P., Larose, Catherine, Schuler, Thomas, Luks, Bartłomiej, Koziol, Krystyna, Spolaor, Andrea, Barbaro, Elena, Martma, Tõnu, Pelt, Ward, Wideqvist, Ulla, Ström, Johan
• Format: Text
• Language: English
• Published: 2021
• Subjects: Arctic; Greenland; Ny-Ålesund; Svalbard; Svalbard Archipelago; albedo; glacier; Ny Ålesund; Siberia
• Online Access: https://doi.org/10.5194/acp-21-3035-2021; https://acp.copernicus.org/articles/21/3035/2021/

Light-absorbing carbonaceous aerosols emitted by biomass or fossil fuel combustion can contribute to amplifying Arctic climate warming by lowering the albedo of snow. The Svalbard archipelago, being near to Europe and Russia, is particularly affected by these pollutants, and improved knowledge of their distribution in snow is needed to assess their impact. Here we present and synthesize new data obtained on Svalbard between 2007 and 2018, comprising measurements of elemental (EC) and water-insoluble organic carbon (WIOC) in snow from 37 separate sites. We used these data, combined with meteorological data and snowpack modeling, to investigate the variability of EC and WIOC deposition in Svalbard snow across latitude, longitude, elevation and time. Overall, EC concentrations ( <math xmlns="http://www.w3.org/1998/Math/MathML" id="M1" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>C</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">EC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="28pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="6a389eec55a273c593d28a49f6bb0e5c"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00001.svg" width="28pt" height="16pt" src="acp-21-3035-2021-ie00001.png"/></svg:svg> ) ranged from <1.0 to 266.6 ng g −1 , while WIOC concentrations ( <math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>C</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">WIOC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="32pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="a7a7591973d6bc98536c066f560a7f1a"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00002.svg" width="32pt" height="16pt" src="acp-21-3035-2021-ie00002.png"/></svg:svg> ) ranged from <1 to 9426 ng g −1 , with the highest values observed near Ny-Ålesund. Calculated snowpack loadings ( <math xmlns="http://www.w3.org/1998/Math/MathML" id="M7" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>L</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">EC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="28pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="0526c74bea7fa17d099d312958f99776"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00003.svg" width="28pt" height="16pt" src="acp-21-3035-2021-ie00003.png"/></svg:svg> , <math xmlns="http://www.w3.org/1998/Math/MathML" id="M8" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>L</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">WIOC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="31pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="ec30e4dcc00ac8ab2ded5658b95a2bb0"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00004.svg" width="31pt" height="16pt" src="acp-21-3035-2021-ie00004.png"/></svg:svg> ) on glaciers surveyed in spring 2016 were 0.1 to 2.6 mg m −2 and 2 to 173 mg m −2 , respectively. The median <math xmlns="http://www.w3.org/1998/Math/MathML" id="M11" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>C</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">EC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="28pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="ecbefc87bd48f7a34186257ed63cd7c0"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00005.svg" width="28pt" height="16pt" src="acp-21-3035-2021-ie00005.png"/></svg:svg> and the <math xmlns="http://www.w3.org/1998/Math/MathML" id="M12" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>L</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">EC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="28pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="9077390bece81e4d9871adee022ac027"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00006.svg" width="28pt" height="16pt" src="acp-21-3035-2021-ie00006.png"/></svg:svg> on those glaciers were close to or lower than those found in earlier (2007–2009), comparable surveys. Both <math xmlns="http://www.w3.org/1998/Math/MathML" id="M13" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>L</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">EC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="28pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="6e6eb10485e0f9f412d7192ceff171df"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00007.svg" width="28pt" height="16pt" src="acp-21-3035-2021-ie00007.png"/></svg:svg> and <math xmlns="http://www.w3.org/1998/Math/MathML" id="M14" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>L</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">WIOC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="31pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="b8bcc42792da2031f7593d43a09ba8ff"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00008.svg" width="31pt" height="16pt" src="acp-21-3035-2021-ie00008.png"/></svg:svg> increased with elevation and snow accumulation, with dry deposition likely playing a minor role. Estimated area-averaged snowpack loads across Svalbard were 1.1 mg EC m −2 and 38.3 mg WIOC m −2 for the 2015–2016 winter. An ∼11 -year long dataset of spring surface snow measurements from the central Brøgger Peninsula was used to quantify the interannual variability of EC and WIOC deposition in snow. In most years, <math xmlns="http://www.w3.org/1998/Math/MathML" id="M18" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>C</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">EC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="28pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="d0e1fd24bf495330b83980b121b0d1c4"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00009.svg" width="28pt" height="16pt" src="acp-21-3035-2021-ie00009.png"/></svg:svg> and <math xmlns="http://www.w3.org/1998/Math/MathML" id="M19" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>C</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">WIOC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="32pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="cdee4a6d6f61324881802e61a6d460d6"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00010.svg" width="32pt" height="16pt" src="acp-21-3035-2021-ie00010.png"/></svg:svg> at Ny-Ålesund (50 m a.s.l.) were 2–5 times higher than on the nearby Austre Brøggerbreen glacier (456 m a.s.l.), and the median EC/WIOC in Ny-Ålesund was 6 times higher, suggesting a possible influence of local EC emission from Ny-Ålesund. While no long-term trends between 2011 and 2018 were found, <math xmlns="http://www.w3.org/1998/Math/MathML" id="M20" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>C</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">EC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="28pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="7d2cf8a36a228ea1ae8f54db0d3911cd"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00011.svg" width="28pt" height="16pt" src="acp-21-3035-2021-ie00011.png"/></svg:svg> and <math xmlns="http://www.w3.org/1998/Math/MathML" id="M21" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>C</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">WIOC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="32pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="06babbcb2cbc99a99781cffa1f6b3198"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00012.svg" width="32pt" height="16pt" src="acp-21-3035-2021-ie00012.png"/></svg:svg> showed synchronous variations at Ny-Ålesund and Austre Brøggerbreen. When compared with data from other circum-Arctic sites obtained by comparable methods, the median <math xmlns="http://www.w3.org/1998/Math/MathML" id="M22" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi>C</mi><mi mathvariant="normal">snow</mi><mi mathvariant="normal">EC</mi></msubsup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="28pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="87eb2d1d96337a8f854bb7402a2142a8"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-3035-2021-ie00013.svg" width="28pt" height="16pt" src="acp-21-3035-2021-ie00013.png"/></svg:svg> on Svalbard falls between that found in central Greenland (lowest) and those in continental sectors of European Arctic (northern Scandinavia, Russia and Siberia; highest), which is consistent with large-scale patterns of BC in snow reported by surveys based on other methods.