城市化背景下珠江三角洲区域气候变化特征研究OA

Based on daily temperature,precipitation,wind speed and relative humidity data from national meteorological observation stations from 1990 to 2020,this study analyzes the temporal and spatial characteristics of meteorological environment in the Pear River Delta(PRD).The effects and contributions of urban expansion to meteorological elements variations were quantitatively analyzed based on land use classification data in the PRD.The results showed that from 1990 to 2020,urban expansion was significant in the PRD,with the proportion of urban construction land area increasing from 5.71%to 14.99%.Regional mean annual temperature and annual precipitation showed an increasing trend,while annual strong wind days,annual low wind days,and annual relative humidity showed a weak declining trend.Urban expansion led to the increase of mean annual temperature,with a change rate of 0.05℃·(10 a)-1 and a contribution rate of 20.80%.Urban expansion led to the increase of annual precipitation,with a change rate of 28.80 mm·(10 a)-1 and a contribution rate of 46.24%.Urban expansion led to the increase of annual strong wind days,with a change rate of 1.16 d·(10 a)-1 and a contribution rate of 100%.Urban expansion led to the decrease of annual relative humidity,with a change rate of-0.84%·(10 a)-1 and a contribution rate of-100%.Urban expansion had no obvious effect on annual low wind days.Seasonally,the contribution of urban expansion was the highest for mean temperature in winter.Its contribution to precipitation in summer and autumn was higher than that in spring and winter.Contribution to strong wind days were relatively higher in spring,autumn and winter,and the contributions to relative humidity were high across all four seasons,and the contribution to low wind days was highest in autumn.