To investigate the spatio-temporal distribution characteristics and correlation of water va-por pressure(WVP)and visibility in Henan Province,the spatio-temporal variation of annual average maximum WVP and minimum visibility and the correlation between the two are analyzed by using the dai-ly maximum WVP and daily minimum visibility data from 118 national weather stations in Henan during 1971-2022.The results show that:(1)The annual average maximum WVP displays a distinct rising trend,with an increase rate of 0.25 hPa/decade.The maximum WVP experienced a low-to-high muta-tion in 1998.The most pronounced rise in maximum WVP occurs in the south-central,eastern and north-ern parts of Henan,and the maximum variation range of WVP is mainly located in south-central and southwestern Henan.(2)The annual average minimum visibility shows a pronounced decline trend,with a decrease rate of 0.56 km/decade.The minimum visibility declined sharply in 2014.Spatially,the an-nual average minimum visibility has decreased noticeably in western and southwestern Henan,part of northern Henan,as well as in some regions of Shangqiu and Xinyang,where the visibility varied greatly.(3)A remarkable negative correlation is found between the annual average maximum WVP and the mini-mum visibility in most parts of Henan,and the regional average correlation coefficient is approximately-0.41.The increase(decrease)of the WVP tends to induce a decline(rise)in visibility.
关键词
最高水汽压/最小能见度/时空分布/相关性分析
Key words
maximum water vapor pressure/minimum visibility/spatio-temporal distribution/cor-relation analysis