资源环境科技发展态势分析平台

The influence of synoptic-scale circulation on air temperature variation in the ice-free and glaciated areas on the eastern side of the Antarctic Peninsula (AP) has been analysed. For this purpose, a new classification of atmospheric circulation with 15 synoptic patterns in the AP region was developed using the self-organizing maps technique. The synoptic patterns were compared with air temperature observations from coastal and glacial sites on James Ross Island, northeastern AP, in the period 2005-2015. The most frequent synoptic pattern with a frequency of 13.7% was dominated by a low-pressure centre in the northwestern Bellingshausen Sea, which extended over the AP to the Weddell Sea. On the other hand, the largest inter-annual variability was observed for a synoptic pattern with a low-pressure centre in the southern Bellingshausen Sea. This synoptic pattern also had the highest air temperature anomalies at both investigated sites year-round. Air temperature anomalies at the lower lying site (Mendel station) were the lowest during a high-pressure ridge dominating the AP region due to a combination of local and synoptic-scale processes. At Davies Dome, the glacial site, southerly barrier winds advecting cold air from the ice-covered Weddell Sea during a strong low-pressure system in the Weddell Sea ensured the coldest air temperature anomalies.