Yiwen Shi, Daoyi Gong, Wei Hua, Yi Chen, Xinhua Li
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引用次数: 0
Abstract
In this study, we investigate the changing relationship between the boreal winter Arctic Oscillation (AO) and eastern African precipitation. The results show that the negative correlation has significantly weakened since the late 1970s. And the Arabian anticyclonic circulation changed concurrently with the AO. In the mid-high troposphere, the anomalous anticyclone centred over the Arabian Peninsula in 1980–2020 moved northeastward and weakened compared to 1950–1979. Correspondingly, the anomalous downward motion over eastern Africa significantly weakened compared with that in 1950–1979, corresponding to insignificant precipitation. A further analysis suggests that AO-related Rossby wave trains in the upper troposphere may modulate the Arabian anticyclone. From 1950 to 1979, the wave activity preferred propagating eastward from the Mediterranean to Russia along a high-latitude path. In contrast, during 1980–2020, it tended to emanate southeastward towards Saudi Arabia, with a notably stronger and more eastward extension than in the earlier period.
期刊介绍:
The International Journal of Climatology aims to span the well established but rapidly growing field of climatology, through the publication of research papers, short communications, major reviews of progress and reviews of new books and reports in the area of climate science. The Journal’s main role is to stimulate and report research in climatology, from the expansive fields of the atmospheric, biophysical, engineering and social sciences. Coverage includes: Climate system science; Local to global scale climate observations and modelling; Seasonal to interannual climate prediction; Climatic variability and climate change; Synoptic, dynamic and urban climatology, hydroclimatology, human bioclimatology, ecoclimatology, dendroclimatology, palaeoclimatology, marine climatology and atmosphere-ocean interactions; Application of climatological knowledge to environmental assessment and management and economic production; Climate and society interactions