北冰洋夏秋季大浪事件的特征分析
Characteristics analysis of summer-autumn extreme wave events in the Arctic Ocean
徐枭阳 1张大千 1张录军1
作者信息
- 1. 南京大学 大气科学学院,江苏 南京 210023
- 折叠
摘要
本文利用ERA5再分析资料,使用超阈值方法筛选得到了 1979-2021年 8-10月北冰洋各海域的极端大浪事件数据集,分析了大浪事件的频数、极端波高的变化、海浪能流和浪向分布特征以及大浪事件中的海冰变化.结果表明:随着海冰减少,北极大浪活动范围扩大,除巴伦支海以外的海域都存在大浪活动增多的现象,东西伯利亚海、拉普捷夫海的极端波高以约 3.5 cm/a和 2 cm/a的速度显著增长,事件频数增长到约每年 4起;相比其他海域,拉普捷夫海的大浪浪向以偏南为主,波浪更易传播到冰区,平均能流为 5～8 kW/m.大浪事件伴随的海冰变化主要发生在边缘冰区,与风场方向有关:向冰风场更多时候伴随着海冰减少,而离冰风场更多伴随着海冰增加.
Abstract
This study used ERA5 reanalysis data to collect an extreme wave event dataset for various regions in the Arctic Ocean during August to October from 1979 to 2021.The analysis focused on the frequency of extreme wave events,changes in extreme wave heights,features of wave power and wave direction distribution,as well as the change of sea ice during wave events.The results suggest that as sea ice decreases,the range of extreme wave activ-ity in the Arctic expands.All regions,except the Barents Sea,exhibit an increase in the occurrence of extreme wave events.In particular,extreme wave heights in the East Siberian Sea and Laptev Sea have significantly increased at rates of approximately 3.5 cm/a and 2 cm/a,respectively,with event frequency reaching around 4 events per year.The dominant wave direction in the Laptev Sea is southerly,facilitating more frequent wave propagation into the ice zone compared to other seas,with an average wave energy flux ranging from 5-8 kW/m.The changes in sea ice within extreme wave events primarily occur in the marginal ice zones and are associated with wind direction:sea ice is more likely to decrease with on-ice winds,while it is more likely to increase with off-ice winds.
关键词
北冰洋/海浪/海冰/极端事件/POT方法Key words
Arctic Ocean/ocean wave/sea ice/extreme event/POT method引用本文复制引用
基金项目
国家自然科学基金项目(42175172)
国家自然科学基金项目(41975134)
出版年
2024
NETL
NSTL
万方数据