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arXiv · 2403.06193

The influence of orography and the direction of prevailing winds on precipitation distributions

Alexander V. Kochin
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Abstract

The general circulation of the atmosphere (GCA) carries out a constant and unidirectional transfer of air masses, therefore its influence is manifested in the distribution of precipitation around the globe due to the occurrence of rain shadow behind mountain barriers. Over the territory of Russia, GCA manifests itself in the form of westerly winds, which cause a decrease in precipitation on the leeward side of the Ural Mountains and the Central Siberian Plateau. The contribution of the orographic component to the spatial variability of precipitation on average reaches 50-60% of the monthly precipitation amounts. Forecasting the magnitude of the orographic effect is close to predicting the transfer rates in GCA, the measurement of which has not yet been satisfactorily provided. A possible promising way to solve the problem is to develop special algorithms similar to those used for detecting Madden-Julian oscillations.

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Alexander V. Kochin. 2024-03-10. The influence of orography and the direction of prevailing winds on precipitation distributions. https://arxiv.org/abs/2403.06193

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