Variations of high temperature from 1961 to 2019 in Liaoning Province, China

Ying Yong Sheng Tai Xue Bao. 2021 Nov 15;32(11):4059-4067. doi: 10.13287/j.1001-9332.202111.038.

Abstract

Better understanding of the changes in high-temperature would be helpful for improving the monitoring of hot extremes and mitigating their impacts towards a sustainable regional development. Based on the data of daily maximum temperature, relative humidity, and wind speed from 23 meteorological stations in Liaoning Province in summer (June to August) during 1961 to 2019, we analyzed the variations of daily maximum temperature (Tx), daily maximum apparent temperature (AT), and heat wave events (3 consecutive days ≥35 ℃). The effects of meteorological variables on daily maximum apparent temperature were examined by the grey relational analysis method. The results showed that the average Tx (AT) of all stations was 26.19 (27.35), 28.29 (31.13), and 28.14 (31.08) ℃, respectively, while the average trends in Tx (AT) was 0.17 (0.38), 0.20 (0.35), and 0.17 (0.28) ℃·(10 a)-1, respectively, in June, July and August during 1961 to 2019. The average AT and its trends in each month were larger than the Tx. From June to August, there was significant negative correlation between Tx (AT) and its climate tendency rate, indicating that the range of warming in the area with low Tx and AT was larger than that in the area with high values. We should therefore pay more attention to the protection against high temperature in the low value area of Tx and AT in summer. From June to August, the average number of hot days with AT ≥ 35 ℃ was 0.85 d·a-1, with an average increase rate of 0.20 d·(10 a)-1. Hot days were signifi-cantly more in June and July than in August. The area with more hot days was mainly located in the west of Liaoning, and the area with less hot days was mainly located in the south and coastal areas. The number of heat wave events was 0.071 times per year, which was large in western Liaoning. There was no high temperature heat wave event in the southern and coastal areas of Liaoning. The correlation analysis showed that the AT in June was strongly associated with relative humidity, while AT in July and August had the closest relationship with Tx. Therefore, the importance of relative humidity on the monitoring and forecasting of high temperature and hot weather cannot be ignored.

深入理解高温热浪天气的变化特征、辨识其影响因素,对于科学防控高温天气的危害、保障经济社会可持续发展具有重要意义。本研究基于1961—2019年6—8月辽宁省23个气象站点的日最高气温、相对湿度和风速数据,分析日最高气温(Tx)、日最高体感温度(AT)和高温热浪(连续3 d≥35 ℃)的变化特征,并采用灰色关联度分析气象因子对AT的影响。结果表明: 1961—2019年,辽宁省各站点6、7和8月Tx的平均值分别为26.19、28.29和28.14 ℃,气候倾向率平均值分别为0.17、0.20、0.17 ℃·(10 a)-1,AT的平均值分别为27.35、31.13、31.08 ℃,气候倾向率平均值分别为0.38、0.35、0.28 ℃·(10 a)-1。6—8月,研究区各站点Tx、AT与其气候倾向率均呈显著负相关关系,说明夏季Tx、AT低值区的增温幅度大于高值区,应重视研究区夏季Tx、AT低值区的高温防御。6—8月,各站点日最高气温≥35 ℃日数平均值为0.85 d·a-1,6、7月明显大于8月,高值区主要位于辽宁西部,低值区主要位于辽宁南部和滨海地区,平均增加速率为0.20 d·(10 a)-1。各站点多年平均高温热浪次数为0.071次,高值区主要分布在西部地区,南部和滨海地区未出现高温热浪事件。关联度分析表明,6月最高体感温度与相对湿度关系最密切,而7月和8月最高体感温度与最高气温关系最密切。因此,在高温天气预报预警中应充分考虑相对湿度的影响。.

Keywords: Liaoning Province.; apparent temperature; high temperature and heat wave; relational analysis; maximum temperature.

MeSH terms

  • China
  • Climate*
  • Hot Temperature*
  • Seasons
  • Temperature