Nonhomogeneous poisson process model of summer high temperature extremes over China

Meng Gao,Aidi Zhang,Han Zhang,Yueqi Wang

doi:10.1007/s00477-021-02149-z

Abstract

In this study, nonhomogeneous Poisson process (NHPP) models arising from the extreme value theory have been fitted to summer high temperature extremes (HTEs) at 321 meteorological stations over China. The seasonality and six prominent atmospheric teleconnection patterns in Northern Hemisphere are incorporated in the NHPP models reflecting the non-stationarity of occurrence rate in Poisson process of HTEs. In addition, Poisson regression model has also been applied to link HTEs and these teleconnection patterns. The linkages of HTEs and teleconnection patterns have been identified in both NHPP modeling and Poisson regression. Composite maps of differences of 500-hPa geopotential height and wind fields in the positive and negative phases of teleconnection patterns are constructed to show the impacts of atmospheric circulation patterns on extreme heat events. The spatial pattern of the associated anticyclonic or cyclonic circulations with teleconnection patterns partly explains the spatial variability of the occurrences of summer HTEs over China.

Highlights

Climate change, especially global warming, has been shown to exacerbate and trigger certain climate extremes, including extreme heat waves and intense precipitation events (Easterling et al 2000)
The nonhomogeneous Poisson process (NHPP) modeling of these two stations is validated by inspecting the residual qq-plot, which does not show any evidence against the fitted NHPP models
We have fitted a NHPP model to the summer High temperature extremes (HTEs) over China in order to find the linkages between summer HTEs and large scale atmospheric teleconnection patterns in the Northern Hemisphere

Summary

Introduction

Especially global warming, has been shown to exacerbate and trigger certain climate extremes, including extreme heat waves and intense precipitation events (Easterling et al 2000). High temperature extremes (HTEs) are among the most frequently investigated climate extremes because of their disastrous impacts on human society and ecosystems (Stott et al 2004; Brown et al 2008; Robeson et al 2014; Gao and Franzke 2017; Dosio et al 2018; Luo et al 2020). The variations of HTEs and its associations with climate change and human activities have been extensively documented in previous literatures (Meehl et al 2004; IPCC 2012; Luo and Lau 2017). Unlike the warming trend of global mean temperature, changes in temperature extremes at regional and local scales are diverse (Brown et al 2008). At a relatively shorter time scale, atmospheric circulation patterns are considered to be responsible for the changes in temperature extremes (Loikith et al 2012; Gao et al 2019a). The associations of atmospheric and oceanic teleconnection patterns with HTEs have received wide attentions in recent decades (Kenyon and Hegerl 2008; Keellings and Waylen, 2015; Carney et al 2020; Luo et al 2020; Tu and Yan 2021)

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Conclusion