Chapter 8 - Reconstruction of Quaternary climate in Svalbard: CRN as proxy

Abstract

Polar region experienced a large-scale melting of glaciers and sea ice retreat in the recent past. Drastic decrease of ice cover and its foreseen impact on ocean circulations, sea level, and ocean chemistry brought Arctic into the forefront of climate change studies. High-latitude glaciers withstand minor climatic change. However, recent trend of global climatic conditions started influencing polar ice sheet and glacier to an alarming state. Compared to lower latitudes, Arctic is significantly affected by minor changes in temperature and precipitation pattern, referred as “Arctic amplification.” Ice dynamics and impact of climate change on Antarctica ice sheet is different than the Arctic Circle as the surrounding environment and atmospheric circulations acting in these areas are diverse in nature. External forces like Milankovitch Cycles and solar irradiance; atmospheric forces like greenhouse gas concentrations, albedo, and cloud cover; and interaction among these forces are key factors responsible for prevailing climate and its changes in the Arctic Circle. Since few decades, Arctic Circle witnessed complex atmospheric, oceanic, and terrestrial changes. Location of Svalbard archipelago is very crucial in terms of the ocean circulation as it is lying between North Atlantic Ocean and Arctic Ocean. The climate here is largely governed by the North Atlantic Oscillation and thermohaline circulation. However, rise in annual average temperature of Arctic is linked to increase in CO2 concentration and decrease in SO4 gas in the atmosphere. Study suggests that role of SO4 concentration in the atmosphere is more important than the solar irradiation in the Arctic climate. Therefore it is essential to understand how climate has responded to external and atmospheric forces. Svalbard located in the North Atlantic sector of Arctic region has shown a high response to present climate changes due to multiple feedback mechanisms associated with oceanic, atmospheric, and cryosphere processes.