Assessment of Seasonal Variability of Extreme Temperature in Mainland China under Climate Change

Weixiong Yan,Junfang Zhao,Yunxia Wang,Jianping Li

doi:10.3390/su132212462

Abstract

Some studies have suggested that variations in the seasonal cycle of temperature and season onset could affect the efficiency in the use of radiation by plants, which would then affect yield. However, the study of the temporal variation in extreme climatic variables is not sufficient in China. Using seasonal trend analysis (STA), this article evaluates the distribution of extreme temperature seasonality trends in mainland China, describes the trends in the seasonal cycle, and detects changes in extreme temperature characterized by the number of hot days (HD) and frost days (FD), the frequency of warm days (TX90p), cold days (TX10p), warm nights (TN90p), and cold nights (TN10p). The results show a statistically significant positive trend in the annual average amplitudes of extreme temperatures. The amplitude and phase of the annual cycle experience less variation than that of the annual average amplitude for extreme temperatures. The phase of the annual cycle in maximum temperature mainly shows a significant negative trend, accounting for approximately 30% of the total area of China, which is distributed across the regions except for northeast and southwest. The amplitude of the annual cycle indicates that the minimum temperature underwent slightly greater variation than the maximum temperature, and its distribution has a spatial characteristic that is almost bounded by the 400 mm isohyet, increasing in the northwest and decreasing in the southeast. In terms of the extreme air temperature indices, HD, TX90p, and TN90p show an increasing trend, FD, TX10p, and TN10p show a decreasing trend. They are statistically significant (p < 0.05). This number of days also suggests that temperature has increased over mainland China in the past 42 years.

Highlights

The global surface temperature was 1.09 ◦ C higher in last the last decade than1850–1900, which was more likely not higher than for any multi-century average during the Holocene [1]
In the last part of the paper, we evaluate the spatial distribution of the trend in extreme air temperature indices trends and examine the temporal evolution of the regional averages of these indices using linear trend rates
It this may be related to the methods data.predictions, it was found that extreme warm events have site, reanalyzed data, orand model increased significantly, while extreme cold events have decreased significantly in China

Summary

Introduction

The global surface temperature was 1.09 ◦ C higher in last the last decade than. 1850–1900, which was more likely not higher than for any multi-century average during the Holocene [1]. The frequency and intensity of hot extremes have increased and those of cold extremes have decreased on the global scale since 1950 [1]. Agriculture is one of the most directly affected sectors by global climate change, especially crop production and food security [2]. China is the largest food-producing country in the world. In 2020, the sown area of grain reached

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Conclusion