山西不同强度霾天气的气候特征及影响因子初探

Climatic Characteristics and Influencing Factors of Different Intensities of Haze Weather in Shanxi

为了揭示山西不同强度、不同范围霾天气发生的气候特征和气候变化及其相关联的气象要素变化对霾天气发生的影响,利用1980—2012年山西108站霾观测资料,研究山西不同范围和不同强度霾日的时空分布及变化趋势;采用统计分析方法,研究风力、降水、平均相对湿度等条件的变化对霾日增减趋势的影响。结果表明:(1)山西不同强度的霾日都具有盆地多于山区,南部多于北部,高值区总体呈东北—西南走向,随海拔高度的升高霾日逐渐减少的空间分布特征;轻微霾和轻度霾分别在太原盆地和临运盆地发生的日数最多;中度霾和重度霾在临运盆地和长治盆地发生的日数最多;临运盆地的侯马是全省各种强度霾日的高发中心。(2)秋冬是出现区域性以上和中等强度以上霾日的多发季节,其中12月和1月是区域性以上霾日的多发时段,11月是重度霾的多发时段;春季风力大,夏季降水日数多是区域性以上和中等强度以上霾天气少发的主要原因。(3)轻微、轻度、中度和重度霾日分别以48 d/10 a、15 d/10 a、3 d/10 a和3 d/10 a的速率增多;小范围、区域性以及大范围的霾日分别以26 d/10 a、46 d/10 a和1.88 d/10 a的速率增多;区域性的霾日增多出现在1995年以后,大范围的霾日增多出现在2003年以后;(4)风速<3 m/s时,风力与霾天气为正相关,相关系数高达0.807;风速≥5 m/s时,风力与霾日数的增减为反相关,相关系数为-0.815;(5)年降水日和日平均相对湿度≥80%日的增减对年霾日变化影响显著,尤其是区域性以上的年降水日增减对年霾日的增减变化影响更显著。

In order to reveal the climatic characteristics of various scopes and different intensities of hazeweather, and the effects of climate change and its associated meteorological elements variation on haze, thespatial and temporal features and variation trend of the haze days in various scopes and different intensitieswere studied by using the haze observation data of 108 stations in Shanxi in 1980-2012. And a correlationanalysis between the varieties of the haze weather and meteorological conditions of wind, precipitation andaverage relative humidity was accomplished by employing the statistical method. The results showed that：（1）different intensity of haze occurred more in basins and the south than in hills and the north, the high center ofwhich had a distribution pattern of northeast to southwest, and with rising altitude, the frequency of haze daysgradually diminished; the slight and mild haze weather appeared most frequently in Taiyuan Basin and LinyunBasin, however, the moderate and severe haze appeared most frequently in Linyun Basin and Changzhi Basin;Houma in Linyun Basin was the center of haze days in the province;（2） autumn and winter were the seasons forhaze weather with regional and moderate to strong intensity, especially December and January were the months with regional and wide- ranging haze weather, while November was the month with moderate and strongintensity haze; there were less haze days because of the strong wind in spring and more precipitation insummer;（3） the slight, mild, moderate and severe haze days were increasing respectively at a rate of 48 d/10 a,15 d/10 a, 3 /10 a and 3 d/10 a, while the small-ranging, regional and wide-ranging haze days rose at a rate of26 d/10 a, 46 d/10 a, and 1.88 d/10 a. In 1995 and 2003, regional and wide- ranging haze days began toincrease;（4） when the wind was lighter than 3 m/s, the wind force had a positive correlation with haze weather,and the correlation coefficient was up to 0.807; but when the wind was stronger than 5 m/s, the correlationcoefficient turned to be negative, which was-0.815;（5） annual precipitation days and days of daily averagehumidity ≥ 80% had obvious effect on the amount variation of the annual haze days, especially the annual daysof regional or large range of precipitation.