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In 2018/19 winter, the Yangtze–Huai River Basin (YHRB, one of the most developed areas in China) experienced an extremely pluvial condition with excessive and long-duration precipitation. Other three extremely pluvial winters during 1979/80–2018/19: 1997/98, 2002/03 and 1989/90 winters were also found. In 2018/19, 2002/03 and 1997/98 winters, similar low-level circulation pattern of anomalous southwesterlies (southeasterlies) over the southern (northern) YHRB was found. However, we found different tropical ocean states for the events. In 2018/19 winter, a combination of a moderate El Niño in the tropical Pacific and warm sea surface temperature (SST) anomalies in the tropical western Indian Ocean (IO) and Atlantic was seen. In 1997/98 winter, we found an extreme eastern Pacific El Niño with warm SST anomalies in the western tropical IO. In 2002/03 winter, a central Pacific El Niño occurred. In contrast, no significant warm SST anomalies were seen in 1989/90 winter. Based on coupled model numerical experiments, the tropical SST anomalies contributed almost half of the YHRB precipitation anomalies in 2018/19 and 1997/98 winters. In particular, the tropical IO warm SST anomalies induced anomalous anticyclones over the South China Sea and northeastern China, with moisture convergence over the YHRB. In 2002/03, the tropical Pacific SST anomalies contributed almost half of the YHRB precipitation anomalies, although its contribution could be reduced due to the inter-basin interactions. For 1989/90 winter, we discussed possible impacts of mid-high latitude wave trains. The results indicate the complexity and diverse potential predictability among the four extreme pluvial winters.kindly check and conform the processed affliations was correct [1,2]Yes, we have checked that. The affliations are correct. [ABSTRACT FROM AUTHOR]

The present study analyzed a long-term record of major floods over Bangladesh under the influence of El Niño–Southern Oscillation (ENSO). Bangladesh is highly vulnerable to floods, and ENSO has a great influence on it. El Niño (La Niña) represents the warm (cold) phase of the ENSO cycle. Southern Oscillation Index data and a long-term flood records have been identified from National Oceanic and Atmospheric Administration, Bureau of Meteorology, Australia, and historical archives, respectively. Synoptic features—precipitation, wind, geopotential height, precipitable water, relative humidity, and surface runoff data—were used to examine the influence of ENSO. Result shows that the Indian summer monsoon contributes the major flood events and largely influenced by both El Niño and La Niña events, with a slightly higher frequency for the latter. Physical mechanisms (distribution of precipitation, wind, geopotential height, precipitable water, relative humidity, and surface runoff) supported these flood events; however, they are quite distinct during El Niño and La Niña condition. Moreover, ENSO's impacts to the Bangladesh region are different to the west part of the monsoon region. Therefore, if ENSO forecast is reliable, the predictability of the monsoon-related flood events can be improved. [ABSTRACT FROM AUTHOR]