Chemical Composition of Snow-Water and Scavenging Ratios over Costal Antarctica

Abstract

Snow samples and aerosol samples were collected at coastal Antarctica near Larsemann Hills and Maitri, during the 29 th Indian Antarctic Expedition carried out during Dec., 2009 to March 2010. The main objective of this study was to characterize the chemical composition of fresh and surface snow at coastal Antarctica and to determine the scavenging ratios using composition of snow and aerosol samples. The pH of surface and fresh snow were 6.03 and 5.64 respectively. The surface snow samples were collected along a 127-km transect from the seaward edge of the ice shelf to the Antarctic plateau and analyzed for the presence of the major inorganic components SO 4 2-, NO was also found in the both fresh and surface snow which may be attributed to the long range transport from Northern Hemisphere as well as to the oxidation of DMS produced by marine phytoplankton. A higher percentage of the ions in fresh snow may be because of trapping of the particulate matter in it. The sea-salt components i.e., Na + , Cl -and Mg 2+decreased with increasing distance from the coast. The acidic components were neutralized mainly by NH 4 + and Ca 2+ . The scavenging ratio was maximum for Na + and minimum for NO 3 -, indicating that the scavenging efficiency was higher for coarse size particles and lower for fine size particles. In addition, we have attempted to find out the possible sources of the observed chemical species in snow-water.

Long Range Transport and Wet Deposition Fluxes of Major Chemical Species in Snow at Gulmarg in North Western Himalayas (India)

“…Scavenging coefficients, scavenging rate, rain-out efficiencies and scavenging ratios are some reported parameters to demonstrate the scavenging of air pollutants (Hicks, 2005). In the present study, we have been estimated scavenging ratios (SR) assuming that the concentration of a chemical species in precipitation is related to its concentration in surface air using the following calculations (Granat et al, 2002;Kulshrestha et al, 2009 (Granat et al, 2002;Kulshrestha et al, 2009;Budhavant et al, 2014a). Encinas and co-workers (2004) have suggested that particle size, and hygroscopicity, cloud type and rain intensity are the major factors affecting the scavenging ratios of aerosols.…”

Snow Chemistry at Mukteshwar in Central Himalayan Region of India

“…The importance of transported dust in the neutralization of acidic components in precipitation samples has been observed globally [30,38]. Very high value of neutralization factor for nssCa 2+ and NH 4 + has been reported in precipitation samples globally [2,30,53,[55][56][57][58][59][60].…”

Chemical composition of aerosol in the atmospheric surface layer of the East Antarctica coastal zone

“…Возможно, этому способствовали отсутствие сезонных работ на станции Молодёжная и её более удалённое от континентов расположение по сравнению со стан циями Новолазаревская (сектор Южной Америки), Прогресс и Мирный (сектор Австралии) . Во многих работах отмечается доминирую щий вклад морской соли и сульфатов, который прослеживается не только в составе атмосферно го аэрозоля, но и в химическом составе поверх ностного и свежевыпавшего снега [11,12,25,29] . Так, повышенные значения К для ионов Ca 2+ , К + и SO 4 2− отмечены в прибрежных районах Антарк тиды: в образцах снега на индийской станции Майтри (Maitri, 70°45′59″ ю .ш ., 11°43′50″ в .д .…”

“…табл . 2) [12] . О преобладающем влиянии континентального фактора в формировании химического состава по верхностного снега свидетельствуют также повы шенные значения К для ионов Ca 2+ , SO выделены следующие пять групп: 1) с концентра циями более 1,0; 2) 0,1-1,0; 3) 0,01-0,1; 4) 0,001-0,01; 5) менее 0,001 .…”