Lagrangian simulations of moisture sources for Northeast China precipitation during 1979–2018

In this study, the FLEXible PARTicle Dispersion Model (FLEXPART) is applied to analyze the moisture sources of Northeast China precipitation from March 1979 to February 2018. The results show that there is mainly one particle aggregation channel in winter, namely the Eastern Europe–Siberia–Lake Baikal–Northeast Asia channel (the western channel). Compared with winter, there are two extra channels in summer, namely the Indochina Peninsula–South China Sea–East China channel (the southern channel) and the Philippine Sea–Ryukyu Islands channel (the southeastern channel). From the long-term mean, Siberia–Mongolia–Xinjiang (SMX) is the most dominant moisture source of Northeast China precipitation in all seasons. As for the moisture contribution rate of each source region to Northeast China precipitation, there is a seesaw interannual relationship between SMX and other source regions. The moisture from the Central–East China is critical to the interdecadal shift of Northeast China summer precipitation. This interdecadal shift is related to the moisture transport from low latitudes to Northeast China, which is modulated by the positive phase of the Pacific Decadal Oscillation and the negative phase of the Atlantic Multidecadal Oscillation.