Increased dust transport from Patagonia to eastern Antarctica during 2000-2020

Abstract

Patagonia is an important dust source for Antarctica due to its proximity. However, the changes in the dust transport from Patagonia to Antarctica during the last two decades remain poorly understood. In this study, we used in-situ observations, remote sensing data, and reanalysis data to show changes in the frequency of dust events in Patagonia and their influence on the dust deposition in eastern Antarctica during the austral springs of 2000-2020. An increasing trend in the frequency of Patagonian dust events was observed from 2000 to 2020, with average frequencies of 3.1 and 8.1 in 2000-2006 and 2007-2020, respectively. The increased dust event frequency in Patagonia was caused by an increase in both the mean wind speed, the downslope wind frequency and air temperature and a decrease in the local soil moisture. The increased Patagonian dust event led to an increasing trend in dust deposition in austral spring from the eastern coast of Patagonia to the northeast of the Antarctic Peninsula and northern Weddell Sea, indicating increasing dust transport from Patagonia to eastern Antarctica from 2000 to 2020. This increased dust transport was related to enhanced westerly winds from Patagonia to the northern Weddell Sea. The increased frequency of circulation patterns conducive to dust events also contributed to the increased transport of Patagonian dust to the Weddell Sea and East Antarctica during 2000-2020.