2018年中国第9次北极科学考察走航期间北极低层大气垂直结构特征分析

CHARACTERISTIC ANALYSIS OF VERTICAL STRUCTURE OF LOWER ATMOSPHERE OVER THE ARCTIC OCEAN DURING CHINARE 2018

利用中国第9次北极科学考察期间获取的大气探空资料,分析了走航期间北极低层大气垂直结构特征。分析发现:(1)对流层中部大气的平均温度递减率为5.67℃·km^(–1),与北极中心区的结果比较一致,高空急流特征比较显著,尤其是高纬地区;(2)本航次观测到的边界层逆温层底高度、厚度和温度差的中位数分别为306 m、299 m和3.2℃,与SHEBA(Surface Heat Budget of the Arctic Ocean)的结果比较一致;(3)低空急流高度和风速的中位数分别为456 m和11.40 m·s^(–1),大多数时次的风速分布在6~14 m·s^(–1)之间;(4)本航次观测到只有67.27%的低空急流高度位于最低逆温层之下,而考虑多层逆温后,92.73%的低空急流位于逆温层之下。

Using the radiosonde data obtained during the 9th Chinese National Arctic Research Expedition(CHINARE 2018),the atmospheric structure characteristics over the Arctic Ocean during the observation period were analyzed.The results showed that:(1)The average of temperature lapse rate in the middle tro-posphere was 5.67℃·km^(−1),which was consistent with that over the central Arctic.The characteristics of high-level jets were remarkable,especially over the high latitude region.(2)The medians of the height of the boundary layer temperature inversion base,the depth of the inversion and the temperature change through the inversion were 306 m,299 m and 3.2℃,respectively,which were consistent with SHEBA(Surface Heat Budget of the Arctic Ocean).(3)The medians of the height of the low-level jet core and the wind speed in the core were 456 m and 11.40 m·s^(−1),respectively,and the wind speed of the jets was mostly distributed within 6–14 m·s^(−1).(4)Only 67.27%of the low-level jets were below the lowest inversions.However,con-sidering multiple temperature inversion layers,92.73%of the low-level jets were beneath the top of the in-versions.