1980—2021年廉江市气温与降水的气候特征

Climatological Characteristics of Air Temperature and Precipitation in Lianjiang from 1980 to 2021

为分析廉江市气候、降水变化特征和演变规律,基于廉江气象站1980—2021年气温、降水量资料,采用线性趋势法、M-K突变检验法、EEMD分解、R/S分析等方法,分析廉江市近41年气温和降水的变化特征。结果表明:1980—2021年廉江市年平均气温以每10年0.18℃的速率呈不显著的上升趋势,其中1983—2003、2012—2019年气温偏高,2004—2011年气温偏低;春秋两季气温则分别呈每10年升高0.7和0.4℃的趋势变化。廉江市年降水以每10年减少21.7 mm的速率呈显著下降趋势,1990—1997、2007—2016年降水偏多,1998—2007、2017—2021年降水偏少,前汛期、后汛期降水的变化速率分别为每10年升高0.8 mm、减少8.7 mm。廉江市年气温在1994年左右发生突变性升高;年降水在2009年左右发生突变性减少。年气温和降水分别具有显著的3.5、3年主周期。未来7~8年,年气温仍保持上升趋势,年降水仍保持下降趋势。

To understand the variation characteristics and evolution patterns of the climate and precipitation in Lianjiang,this work analyzes the variation characteristics of its air temperature and precipitation from 1980 to 2021 based on the data in the 41 years taken at a local meteorological station and with the methods of linear tendency,Mann-Kendall abruptness test,Ensemble Empirical Mode Decomposition(EEMD)and Rescaled Range Analysis(R/S analysis).The results are shown as follows.For the years studied,annual mean air temperatures tend to increase insignificantly at a rate of 0.18℃every ten years,being relatively high from 1983 to 2003 and from 2012 to 2019 and relatively low from 2004 to 2011.Seasonal temperatures show a trend of 0.7℃and 0.4℃increases every ten years in spring and autumn respectively.Annual precipitation amounts tend to drop significantly at a rate of 21.7 mm every ten years,being more from 1990 to 1997 and from 2007 to 2016,and less from 1998 to 2007 and from 2017 to 2021.The variability of precipitation increases by 0.8 mm/ten years for the April-June raining season but decreases by 8.7 mm/ten years for the July-September raining season,respectively.Annual air temperatures increased abruptly around 1994 and annual precipitation decreased abruptly around 2009.They are with significant primary periods of 3.5 and 3 years,respectively.For the seven to eight years to come,the annual air temperature is expected to keep rising while the annual precipitation is forecast to keep falling.