Soot on snow experiments: light-absorbing impurities effect on the natural snowpack
J. Svensson1,2, A. Virkkula1,3,4, O. Meinander1, N. Kivekäs1,5, H.-R. Hannula6, O. Järvinen4, J. I. Peltoniemi4,7, M. Gritsevich4,7,8, A. Heikkilä1, A. Kontu6, A.-P. Hyvärinen1, K. Neitola1, D. Brus1, P. Dagsson-Waldhauserova9,10, K. Anttila1,7, T. Hakala7, H. Kaartinen7, M. Vehkamäki11, G. de Leeuw1,4, and H. Lihavainen11Finnish Meteorological Institute, Helsinki, Finland 2Department of Environmental Sciences, University of Helsinki, Helsinki, Finland 3Institute for Climate and Global Change and School of Atmospheric Sciences, Nanjing University, Nanjing, China 4Department of Physics, University of Helsinki, Helsinki, Finland 5Department of Physics, Lund University, Lund, Sweden 6Arctic Research Center, Finnish Meteorological Institute, Sodankylä, Finland 7Finnish Geospatial Research Institute, Masala, Finland 8Institute of Physics and Technology, Ural Federal University, Yekaterinburg, Russia 9Faculty of Environment, Agricultural University of Iceland, Hvanneyri, Iceland 10Department of Physics, University of Iceland, Reykjavik, Iceland 11Department of Chemistry, University of Helsinki, Helsinki, Finland
Received: 27 Jan 2015 – Accepted for review: 08 Feb 2015 – Discussion started: 26 Feb 2015
Abstract. Light-absorbing impurities affect snow and ice via a decrease in albedo and a consequent disturbance to the radiative energy balance. Experimentally, these matters have only been examined in a few studies. Here we present results from a series of experiments in which we deposited different soot concentrations onto natural snow in different regions of Finland, and thereafter monitored the changes of the snowpack through the melting season. Measurements of the particulates in the snow indicated concentrations in the range of thousands of ppb to have clear effects on the snow properties, including the albedo, the physical snow characteristics, and an increased melt rate. For soot concentrations in the hundreds of ppb range, the effects were not as clearly visible, and it was more difficult to attribute the effects solely to the soot on the snow. Comparisons between our experimental data and the widely used Snow, Ice and Aerosol Radiation (SNICAR) model showed a general agreement when the model was specifically tuned to our measurements. This study highlights the importance of additional experimental studies, to further articulate and quantify the effects of light-absorbing impurities on snow.
Svensson, J., Virkkula, A., Meinander, O., Kivekäs, N., Hannula, H.-R., Järvinen, O., Peltoniemi, J. I., Gritsevich, M., Heikkilä, A., Kontu, A., Hyvärinen, A.-P., Neitola, K., Brus, D., Dagsson-Waldhauserova, P., Anttila, K., Hakala, T., Kaartinen, H., Vehkamäki, M., de Leeuw, G., and Lihavainen, H.: Soot on snow experiments: light-absorbing impurities effect on the natural snowpack, The Cryosphere Discuss., 9, 1227-1267, doi:10.5194/tcd-9-1227-2015, 2015.