Relation between surface topography and sea-salt snow chemistry from Princess Elizabeth Land, East Antarctica

K. Mahalinganathan, M. Thamban, C. M. Laluraj, B. L. Redkar
2011 The Cryosphere Discussions  
Previous studies on Antarctic snow have established an unambiguous correlation between variability of sea-salt records and site specific features like elevation and proximity to the sea. On the other hand, variations of Cl − /Na + ratios in snow have been attributed to the reaction mechanisms involving atmospheric acids. In the present study, the annual records of Na + , Cl − and SO 2− 4 were investigated using snow cores along a 180 km coast to inland transect in Princess Elizabeth Land, East
more » ... izabeth Land, East Antarctica. Exceptionally high Na + concentrations and large variations in Cl − /Na + ratios were observed up to 50 km (∼1100 m elevation) of the transect. The steepest slope in the entire transect (49.3 m km −1 ) was between 20 and 30 km and the sea-salt records in snow from this area revealed extensive modifications, with Cl − /Na + ratios as low as 0.2. Statistical analysis showed a strong association between the slope and variations in Cl − /Na + ratios along the transect (r = −0.676, 99 % confidence level). While distance from the coast accounted for some variability, the altitude by itself has no significant control over the sea-salt ion variability. However, the steep slopes influence the deposition of sea-salt aerosols in snow. The wind redistribution of snow due to the steep slopes on the coastal escarpment increases the concentration of Na + , resulting in a low Cl − /Na + ratios. We propose that the slope variations in the coastal regions of Antarctica could significantly influence the sea-salt chemistry of snow. The Cryosphere, 6, 505-515, 2012
doi:10.5194/tcd-5-2967-2011 fatcat:u5aisn6r5zdpdlrstqfzy2dfoa