Study on the evolution of online public opinion and government response strategies for the “7–20” extraordinary rainstorm and flooding disaster in Zhengzhou, China

Disaster-related online public opinion develops rapidly, the actual situation is complex and volatile, and the public opinion environment should be regulated through appropriate guidance. 2021 Zhengzhou 7–20 extraordinary rainstorm and flooding disaster has attracted widespread public attention. In order to analyze the online public opinion triggered by extraordinary rainstorm disasters and propose targeted management measures so as to improve the comprehensive disaster reduction efficiency. This paper collected information about the “Zhengzhou rainstorm” posted on the Sina Weibo platform from July 11 to August 14, 2021. We analyzed the characteristics of related Weibo from two dimensions: sentiment analysis and thematic analysis. The results are as follows: Online public opinion will be generated rapidly and last for a long time; the different emotional colors change at different periods of the disaster; the focus of online public opinion discussion varies at different periods of the disaster. Given this result, the following suggestions are made: the cooperation level between departments should be improved, and an early warning mechanism for public opinion should be established so that once the relevant public opinion is generated, a quick response can be made; a relevant responsibility mechanism should be established to realize that a specific department is responsible for the handling of public opinion in the corresponding section, to realize a scientific and practical normalized control mechanism for public opinion; Relevant departments should improve the openness and transparency of appropriate handling methods, to establish a public opinion control and guidance mechanism. This study has specific significance for improving the level of governance of online public opinion caused by sudden natural disasters.