近35年广东省区域灰霾天气过程的变化特征及突变分析

Characteristics and abruption analysis on regional haze weather process over Guangdong Province during the recent 35 years

利用广东省86个地面观测站1980-2014年逐日能见度、相对湿度资料,在对＂区域灰霾过程＂与＂单站灰霾过程＂进行定义的基础上,分区域诊断典型灰霾天气过程（即连续三站3d及以上出现灰霾日的天气过程）,并对其长期变化趋势及特征进行分析.结果表明：广东省的灰霾过程主要出现在珠江三角洲、粤北及粤东个别地区,并以珠江口以西的珠江三角西侧最为严重.＂区域灰霾过程＂以日平均能见度在5-10km之间的过程为主,没有出现过日平均能见度低于2km的重度灰霾过程.各＂区域灰霾过程＂的特征有所差异：首先是各＂区域灰霾过程＂出现峰值的时间略有差异.尽管灰霾过程均主要出现在10月-翌年4月,但粤北和粤东、西两翼最多出现在冬季（12月-翌年1月）、春季次之,而珠江三角洲地区则最多出现在春季（3-4月）、冬季次之.其次是各＂区域灰霾过程＂变化趋势的差异.珠江三角洲地区和粤北地区灰霾过程变化趋势比较相似,在2008年以前总体呈增多趋势,珠江三角洲地区增势最为显著的时段是2000-2008年,而粤北地区则是1991-2011年;粤西地区灰霾过程在2000年以前变化都比较平稳,2004年开始快速增多;粤东地区的灰霾过程近35年来虽有小的波动,但总体变化不大,呈稳中略减的趋势.利用M-K法和滑动t检验的突变分析表明,珠江三角洲地区灰霾过程的增多是一种不连续的突变现象,发生突变的时间点是1986年;粤北地区灰霾过程则在1992-1994年出现了突发性增多的现象;粤西地区灰霾过程也在2001年发生了突变.

With the daily visibility and relativity humidity data from 86meteorological stations across Guangdong province from 1980 to 2014, typical haze processes according to the region were diagnosed based on the definition of ＂regional haze process＂ and ＂single station haze process＂. Furthermore, the trends and characteristics of haze process were analyzed. Results showed that the haze processes over Guangdong province mainly occurred in the Pearl River Delta region （PRD） and in individual regions of northern and eastern Guangdong, especially the western area to Pearl River Estuary. The data revealed that ＂Regional haze process＂ was mostly characterized by visibility ranging from 5 to 10km and there was no case with visibility less than 2km. Haze weather processes mainly occurred from October to April with the peak time differing slightly. The haze processes mostly happened in winter （from December to January next year） over northern, eastern and western Guangdong, but in spring （from March to April next year） over PRD. The analysis of the abruption by virtue of the Mann-Kendall rank statistics and the moving-t test revealed that the increasing trends of haze weather process over the PRD since the 1980s were due to abrupt changes which took place in 1986 and reached the strongest between 2000 and 2008. The haze weather process over northern Guangdong also appeared abrupt increasing changes in the middle of 1990s, especially between 1991 and 2011. The annual mean series of haze process over western Guangdong was relatively stable before 2000, but increased significantly after 2004. Haze processes over eastern Guangdong showed no significant changes.