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The Bay of Bengal summer monsoon (BOBSM) is the most prominent branch of the Asian summer monsoon system, which exhibits complex interannual variability. While previous studies have focused on the onset conditions of the BOBSM, less attention has been paid to the retreat of the BOBSM. In this study, we propose an index to measure BOBSM retreat, based on the mean zonal wind field at 850 hPa during the summer‐to‐winter monsoon transitions. By analyzing the climatic characteristics and interannual variability of the BOBSM retreat using this index, we find that BOBSM retreat exhibits significant interannual variability, which is closely related to the occurrence of Indian Ocean Dipole (IOD) events. Statistically, when a positive IOD event takes place in the boreal autumn season, the retreat of the summer monsoon occurs earlier correspondingly. Conversely, the retreat is delayed when a negative IOD event occurs. Plain Language Summary: The South Asian summer monsoon is the most important monsoon system in the world. One of its component branches is the Bay of Bengal summer monsoon (BOBSM), which has a strong impact on local social activities due to its heavy rainfall and associated disasters. While the onset of the BOBSM has received considerable attention, the retreat of the BOBSM has been relatively overlooked, leading to an poor understanding of the BOBSM system. In this study, we focus on the retreat process of the BOBSM, examining its climatological features and interannual variability by introducing a retreat index. We also show the important role played by the Indian Ocean Dipole event in modulating the retreat date on the interannual timescale. Key Points: A Bay of Bengal summer monsoon (BOBSM) retreat index is introduced to reveal the features of monsoon retreatThe climatological condition and interannual variability of BOBSM retreat are studiedThe Indian Ocean Dipole plays an important role in the interannual variability of the BOBSM retreat [ABSTRACT FROM AUTHOR]

The seeds of Camellia oleifera produce high amount of oil, which can be broadly used in the fields of food, industry, and medicine. However, the molecular regulation mechanisms of seed development and oil accumulation in C. oleifera are unclear. In this study, evolutionary and expression analyses of the MADS‐box gene family were performed across the C. oleifera genome for the first time. A total of 86 MADS‐box genes (ColMADS) were identified, including 60 M‐type and 26 MIKC members. More gene duplication events occurred in M‐type subfamily (6) than that in MIKC subfamily (2), and SEP-like genes were lost from the MIKCC clade. Furthermore, 8, 15, and 17 differentially expressed ColMADS genes (DEGs) were detected between three developmental stages of seed (S1/S2, S2/S3, and S1/S3), respectively. Among these DEGs, the STK-like ColMADS12 and TT16-like ColMADS17 were highly expressed during the seed formation (S1 and S2), agreeing with their predicted functions to positively regulate the seed organogenesis and oil accumulation. While ColMADS57 and ColMADS07 showed increasing expression level with the seed maturation (S2 and S3), conforming to their potential roles in promoting the seed ripening. In all, these results revealed a critical role of MADS‐box genes in the C. oleifera seed development and oil accumulation, which will contribute to the future molecular breeding of C. oleifera. [ABSTRACT FROM AUTHOR]

As the upstream region of the Asian summer monsoon, the Bay of Bengal summer monsoon (BOBSM) system has impacts on rainfall patterns in East Asia. In this study, we investigate the impact of the interannual variability of the BOBSM retreat on China precipitation in early summer (June) of the following year. When the BOBSM retreat occurs earlier in the previous year, we find enhanced rainfall in both the northeastern and eastern parts of China. Conversely, when the retreat of the BOBSM is delayed in the previous year, there is a tendency for decreased rainfall in most of northeastern and eastern China, while rainfall in the northern part of the Taiwan island region tends to increase. Statistical analysis demonstrates the co-variability between China's June precipitation anomalies and preceding wind anomalies in the eastern Bay of Bengal. The results indicate a strong relationship between the preceding BOBSM retreat and China precipitation anomalies in the following June. Furthermore, the analysis suggests that the BOBSM retreat is more of an independent signal rather than modulated by an Indian Ocean Dipole event. [ABSTRACT FROM AUTHOR]

We investigate interdecadal differences in the interannual variability of the South China Sea (SCS) Winter Monsoon (SCSWM) since 1950. The SCSWM is influenced by both the East Asian Winter Monsoon (EAWM) over the mid–high latitudes and the anomalous anticyclone over the western North Pacific (WNPAC). The EAWM tends to cause a positive linear correlation of wind speeds between the northern SCS (NSCS) and the southern SCS (SSCS). Because the cold surge of the EAWM can make wind speeds over the NSCS and SSCS increase simultaneously. While, the WNPAC tends to weaken this positive correlation (corNS) because anomalies associated with the WNPAC will decrease wind speeds over the NSCS but exert a small or even an opposite influence on wind speeds over the SSCS. The interannual variation of the EAWM before the late 1970s is greater than that after the early 1990s. And the WNPAC was weak and confined to the east of the SCS before the late 1970s but became strong and expanded towards the SCS after the early 1990s. As a result, the positive corNS was significant at the 95% confidence level before the late 1970s but became insignificant after the early 1990s. [ABSTRACT FROM AUTHOR]