Advances in Remote Sensing Technology and the Three Poles

29 Spatio-Temporal Variations of Aerosols Over the Polar Regions Based on Satellite Remote Sensing

Rohit Srivastava^*

National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Government of India, Goa, India 403804 ^* Corresponding author

29.1 Introduction

Atmospheric aerosols are tiny solid particles suspended in the air medium having a size range of 0.001 to 100 μm. Aerosols are mainly produced by both natural as well as anthropogenic activities. Black carbon (soot), organic carbon (OC), sulfates, nitrates, mineral dust, and sea salt are the major aerosol species. Aerosols are mostly formed in nature by wind-blown dust, sea salt from breaking sea waves, forest fires, volcanic activities (directly emitted and formed due to gas to particle conversion), biogenic aerosol production, and natural gas to particle conversion products. e.g., sulfate aerosols formed by dimethyl sulfide emitted from the ocean surface. Vehicular, industrial exhausts, soil erosion in agriculture, open mining, and crop residue burning are the main anthropogenic activities that give rise to this particulate matter (aerosols) in the atmosphere.

Different removal processes reduce aerosols from the atmosphere. For larger aerosols, dry deposition (sedimentation) is a more effective removal procedure in which the aerosols settle down owing to gravity. The most efficient sink process for particles smaller than 1 μm is wet deposition, which is classified into three categories: rainout, washout, and ...