Summer precipitation over the Maritime Continent (MC) is tightly connected to livelihoods of the locals, and the corresponding strong convective activities are also crucial to Asian regional climate variations remotely. Using observational and reanalysis data from 1958 to 2020, we found that El Niño with different decay rates can cause different summer precipitation anomalies in the MC area. In the fast decaying (FD) El Niño summer, the MC area shows a precipitation surplus, while the MC precipitation decreases during the slow decaying (SD) El Niño summer. For the FD El Niño, the equatorial central-eastern Pacific warm sea surface temperature (SST) anomaly quickly turns into cold in the decaying summer, while the SST over MC region sustains a warm anomaly owing to the Indo-western Pacific Ocean capacitor effect. This local warm SST anomaly leads to anomalous ascent and then excessive precipitation, further stimulating low-level easterly wind to east of the MC with increased water vapor transport. For the SD El Niño, the central-eastern Pacific warm SST anomaly sustains till the decaying summer, continuously adjusting the Walker circulation. An anomalous local descent motion associated with the weakened Walker circulation region hampers the MC precipitation in summer. Our findings benefit the local researches of the MC summer climate variations, and potentially favor the regional climate predictions.

中文翻译：

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在快速和缓慢衰减的厄尔尼诺情况下，海洋大陆的夏季降水异常相反


海洋大陆 （MC） 的夏季降水与当地人的生计密切相关，相应的强对流活动对亚洲区域远程气候变化也至关重要。利用 1958 年至 2020 年的观测和再分析数据，我们发现具有不同衰减速率的厄尔尼诺现象会导致 MC 地区出现不同的夏季降水异常。在快速衰减 （FD） 的厄尔尼诺夏季，MC 区表现出降水盈余，而在缓慢衰减 （SD） 的厄尔尼诺夏季，MC 降水减少。对于 FD 厄尔尼诺现象，赤道中东太平洋暖海面温度 （SST） 异常在衰败的夏季迅速变为寒冷，而 MC 区域的 SST 由于印度-西太平洋电容器效应而维持温暖异常。这种局部暖海温异常导致异常上升，然后导致过度降水，进一步刺激 MC 以东的低层东风，增加水汽输送。对于 SD 厄尔尼诺现象，中东部太平洋暖海温异常一直持续到衰败的夏季，不断调整沃克环流。与减弱的 Walker 环流区相关的异常局部下降运动阻碍了夏季 MC 降水。我们的研究结果有利于 MC 夏季气候变化的局部研究，并可能有利于区域气候预测。