Sampans by Hankou Bund during 1931 floods, Wuhan. They found that the flood resulted from the combined impacts of tropical El Nino– associated sea surface area temperature level forcing and extratropical wave activities over the Eurasian continent. They likewise suggested that the flood was a preconditioned compound event, possibly exacerbated by preceding springtime heavy rainfall.
The researchers found that the persistent rainfall in July 1931 was associated with a consistent western Pacific subtropical high (WPSH). This consistent westward expansion of the WPSH anchored the rainband along the Yangtze River, speeding up the disaster.
By Institute of Atmospheric Physics, Chinese Academy of Sciences
September 10, 2023
A photo of Hankow municipal government in the 1931 flood. In the summer season of 1931, the Yangtze River flood in eastern China became one of historys most dangerous catastrophes, impacting over 25 million individuals and declaring 2 million lives.
The 1931 Yangtze River flood affected 25 million people and took 2 million lives. Recent research links the catastrophe to both tropical and extratropical elements, with insufficient flood control steps exacerbating its impact.
In the summertime of 1931, an extraordinary disaster unfolded along the Yangtze River basin in eastern China– the 1931 Yangtze River flood, referred to as one of historys deadliest natural catastrophes. This catastrophic event immersed an incredible 180,000 km2, affected 25 million lives, and tragically claimed over 2 million lives.
In spite of its tremendous societal impact, the origins of this significant flood have actually remained mostly untouched, a challenge compounded by the scarcity of historic records and pre-1950s meteorological information in China. Recent access to vital historic datasets has, however, opened the capability to investigate the 1931 Yangtze River flood.
Sampans by Hankou Bund during 1931 floods, Wuhan. Collected by John ( Jack) William Ephgrave, readily available at Historical Photographs of China under recommendation number Ep01-262, University of Bristol. Credit: John ( Jack) William Ephgrave
Recent Research Findings
A recent study published in the Journal of Climate has investigated the truths and underlying systems of the 1931 Yangtze River flood. They discovered that the flood arised from the combined results of tropical El Nino– related sea surface area temperature forcing and extratropical wave activities over the Eurasian continent. They likewise suggested that the flood was a preconditioned compound occasion, possibly aggravated by preceding springtime heavy precipitation.
Leading this research effort was Prof. Tianjun Zhou of the Institute of Atmospheric Physics (IAP) at the Chinese Academy of Sciences. The research study hinged on a variety of engaging proof, including critical observations, reanalysis datasets, and simulations carried out with atmospheric general flow designs driven by historic sea surface area temperatures.
” We found that the flooding in 1931 along the Yangtze River valley was driven by July rains. While the July 1931 rains amounts to rank second over the past century, they surpassed those of many other pluvial years in between 1951 and 2010 in terms of persistence,” stated Yueqi Zhou, the first author of the research study, a Ph. D trainee from the University of the Chinese Academy of Sciences studying at IAP.
Systems and Aftermath
The researchers found that the consistent rains in July 1931 was associated with a constant western Pacific subtropical high (WPSH). Warm sea surface area temperature level abnormalities in the tropical Indian Ocean, following an El Nino occasion, caused the WPSH to extend southwestward. Simultaneously, the southward shift of the westerly jet, driven by extratropical wave activities, hindered the normal northward progression of the WPSH for July. This consistent westward expansion of the WPSH anchored the rainband along the Yangtze River, precipitating the catastrophe.
In their study, the scientists also examined the flood control and relief efforts regarding this event. They recommended that the lack of adequate preventative, responsive, and adaptive steps contributed significantly to the devastating consequences.
” This historic occasion demands much deeper scrutiny within the climate modification adaptation neighborhood,” stated Prof. Tianjun Zhou, the matching author of the study.
Recommendation: “Understanding the Forcing Mechanisms of the 1931 Summer Flood along the Yangtze River, the Worlds Deadliest Flood on Record” by Yueqi Zhou, Tianjun Zhou, Jie Jiang, Xiaolong Chen, Bo Wu, Shuai Hu and Mingna Wu, 28 August 2023, Journal of Climate.DOI: 10.1175/ JCLI-D-22-0771.1.
