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The Asian‐Australian monsoon (AAM) region is characterized as abundant summer monsoon rainfall, which provides fresh water resources for high‐density population there. The research uses HadGEM3‐A‐N216 model simulations to compare the change of extreme rainfall intensity in the AAM region with and without anthropogenic influences. Although the anthropogenic forcing exerts a weak impact on the climatological mean distribution of the extreme precipitation, it significantly increases the extreme precipitation intensity at each degree in most parts of the AAM region, especially for the northern East Asia, the Bay of Bengal, and Australia. As the extreme degree increases from the 50–98%, the extreme precipitation intensity in the northern East Asia, the Bay of Bengal, and the Australia increase more and more rapidly, while that in the southern East Asia changes from a decreasing trend to an increasing trend. Overall, the stronger extreme precipitation is accompanied by a stronger growth trend under the anthropogenic forcing. [ABSTRACT FROM AUTHOR]

Based on the Twentieth Century Reanalysis version 2 datasets (1871–2010), this article first analyzes the relationships of the Arctic Oscillation (AO) and the El Niño‐Southern Oscillation (ENSO) with the East Asian winter monsoon (EAWM) and further investigates the changes in the relationships between the ENSO (AO) and EAWM before and after removing the AO (ENSO) signal. As revealed by previous studies, an interdecadal oscillating relationship is found between the ENSO and EAWM. This oscillation disappears when the AO signal is removed; however, the ENSO–EAWM relationship has exhibited a stable and significant negative correlation over the past 140 years. In contrast, the oscillating relationship (with a period of approximately 60 years) between the AO and EAWM shows little differences when the ENSO signal is removed. Further analysis reveals the main reasons for the strengthening of the ENSO–EAWM relationship by removing the AO signal. The results show that after removing the AO signal, the ENSO‐induced anomalous sinking branch of the Walker circulation over the western Pacific shifts northwestward, and the ENSO‐related anomalous anticyclone in the northern part of the western Pacific strengthens. Such circulation anomalies are conducive to the establishment of the East Asia–North Pacific teleconnection, which is favourable for the ENSO–EAWM relationship. The above results reveal that there is an interdecadal oscillation in the AO–EAWM relationship and the ENSO–EAWM relationship may be relatively stable, the interdecadal oscillation only occurs under the influence of the AO. These results may improve the use of ENSO for predicting the EAWM on seasonal time scale in the future. [ABSTRACT FROM AUTHOR]

Previous studies have noted that a strong El Niño event occurring in the preceding winter will result in westward stretching of the western North Pacific subtropical high (WPSH) in the following summer, causing anomalously high precipitation in the Yangtze–Huaihe River basin and anomalously low precipitation in southern China. The winters preceding the summers of 1998 and 2016 featured strong El Niño events, which, along with the El Niño event of 1982, represented the strongest El Niño events since 1950. Under these similar El Niño event backgrounds, the July precipitation anomaly in 2016 was similar to that in 1998, but the August precipitation anomalies in the two years featured opposite distributions. According to the atmospheric circulation analysis, we found that an anomalous ascending motion appeared over the Indian Ocean, while an anomalous descending motion appeared over the Pacific Ocean in August 1998. In addition, the WPSH stretched westward over southern China. However, the atmospheric circulation distribution in August 2016 was the opposite of that in 1998, and the WPSH was divided into eastern and western parts by the anomalous western Pacific cyclone. Further analysis showed that the number of tropical cyclones and typhoons over the western Pacific Ocean increased significantly in August 2016, and their activities were concentrated in the South China Sea (SCS)–southern China region and the western Pacific Ocean, resulting in the division of the WPSH. Therefore, the numbers, tracks, and strengths of tropical cyclones and typhoons were responsible for the differences in the anomalous precipitation distributions over the East Asia–Pacific Ocean region between August 2016 and August 1998. [ABSTRACT FROM AUTHOR]