ALBERT

Description: In contrast to the Antarctic coastal region, there are only a few staffed weather stations in the remote plateau region. In particular, inland Dronning Maud Land (DML) on East Antarctic Plateau is one of the regions in which weather observations are the shortest and sparsest in the world. Several automatic weather stations (AWSs) have been installed since 1990s. However, owing to their remoteness and harsh environment, the missing observations occur frequently and these data gaps hinder the analysis of temperature variability and changes in the region. Here, we present complete 40-years long temperature records for Dome Fuji, Relay Station, and Mizuho in the inland DLM region, in which observations have been corrected, and gaps have been filled using the state-of-the-art global atmospheric reanalysis data. The records show the similar interannual variability among each station. A stacked annual temperature reveals a statistically significant warming trend since the late 1990s. The most rapid warming is observed during the austral spring. The springtime warming resulted from an increase of warm northerly winds associated with the enhanced cyclonic anomaly in the Weddell Sea. The circulation changes in the Weddell Sea is closely linked to the tropical-polar teleconnection. The impact of changes in tropical sea surface temperatures seem to extend not only to the Antarctic Peninsula and West Antarctica, but also to the East Antarctic Plateau.

Description: The Japanese Antarctic Research Expedition (JARE) has been conducting snow stakes observation between Syowa Station and Dome Fuji Station for more than 30 years. This observation has revealed interannual variations in the annual depth of accumulation. In order to clarify the cause of this interannual variation from field observation, it is necessary to know the date and time of the snow surface change and its magnitude. Therefore, we have installed four AWSs equipped with snow depth sensors from 2016 to 2019. This presentation shows the main results as follows: 1) The temporal changes of surface height include stepwise fluctuations and pulse-like fluctuations, and the rise in surface height is mainly caused by stepwise rises, rather than pulse-like fluctuations. The stepwise fluctuations are likely associated with synoptic-scale disturbances. The pulse-like fluctuations are concentrated more in cold season than warm season. 2) A slow decline in surface height was observed during the warm season. 3) The stepwise fluctuations in the inland plateau areas are concentrated more in warm season than cold season.