In recent decades it has been observed that near surface air temperatures are increasing more rapidly in the Arctic than the global average, a process known as Arctic amplification 15, 16. Overall, approximately 6.5 million metric tons of dust are deposited every year between 60°N and 90°N 14. ![]() Accelerated dryland expansion as a result of climate change provides additional sources of dust 13. It is estimated that dust is transported directly to the Arctic in 25% of Asian dust storm events 12. The peak in arctic dust concentration occurs during the spring, which coincides with dust storms in the Gobi and Takliman Deserts 9, 11. The majority of dust transported to the Arctic originates in Asian deserts with smaller contributions from the Sahara Desert 9, 10. Globally, the entrainment of desert particulates is the most significant source of atmospheric mineral dust, contributing to 75% of all aerosols 8. However, the major source of naturally occurring aerosols in the polar region is through the transport of dust from southern latitudes. Locally, retreating ice masses expose fine sediments that can lead to dust storms, particularly in the autumn 7. Non-anthropogenic aerosols, such as mineral dust, are also introduced into the Arctic atmosphere. ![]() Anthropogenic aerosols affect the microphysical structure of arctic clouds, leading to enhanced surface longwave fluxes that are comparable to established greenhouse gases 5, 6. Significant influxes of anthropogenic aerosols occur during the winter and spring as a result of enhanced transport mechanisms coupled with less efficient removal processes 4. A rctic haze, which was first identified in 1956 1, is primarily the result of anthropogenic aerosol pollutants that originate from industrial areas 2, 3. The presence of aerosols in the Arctic environment is well established by researchers.
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