生态环境学报
生態環境學報
생태배경학보
ECOLOGY AND ENVIRONMENT
2013年
8期
1381-1385
,共5页
北京%城市化%气候效应%霾%污染源
北京%城市化%氣候效應%霾%汙染源
북경%성시화%기후효응%매%오염원
Beijing%urbanization%climatic effects%haze%pollution source
近年来,随着超大城市/城市群大气灰霾等复合污染加剧,引起人们对区域生态环境与及公共健康问题越来越多的关注。应用北京地区1980-2012年气候资料及同期城市发展统计指标,统计分析了城、郊区间霾日数的变化特征,并在此基础上探讨了北京城市化及局地气候差异对霾日数的影响。分析表明:北京城区霾日数要明显多于郊区,在2007年以前城、郊区站点均有相似的波动增长趋势,但城区站霾日数增加速率(约21 d/10 a)要远大于郊区站(约7.2 d/10 a);北京各地霾日数与主要城市发展指数之间的相关系数均超过0.001显著性水平,随着城市化而迅速增加的能源消耗和机动车尾气排放是导致北京地区灰霾天气逐渐增多的主要污染源,污染源的不均匀分布是导致城、郊霾日数差异的主要因素。分析还发现,城市化导致的区域气候差异对局地灰霾亦有较明显的影响。伴随着城市化的快速发展,城、郊区气候差异逐渐变大,城市下垫面粗糙度增加导致近地面层风速减小。大城市热岛效应背景下,更容易出现较厚的逆温层,这将阻碍空气垂直方向的对流输送。此外,城区气温持续上升,相对湿度下降,平均风速减小,小风频率增加,也会阻碍空气的水平流通,使得城市排放颗粒污染物的扩散难以扩散,有利于霾日增加。这表明北京地区城市气候效应对区域生态环境具有不可忽视的影响。
近年來,隨著超大城市/城市群大氣灰霾等複閤汙染加劇,引起人們對區域生態環境與及公共健康問題越來越多的關註。應用北京地區1980-2012年氣候資料及同期城市髮展統計指標,統計分析瞭城、郊區間霾日數的變化特徵,併在此基礎上探討瞭北京城市化及跼地氣候差異對霾日數的影響。分析錶明:北京城區霾日數要明顯多于郊區,在2007年以前城、郊區站點均有相似的波動增長趨勢,但城區站霾日數增加速率(約21 d/10 a)要遠大于郊區站(約7.2 d/10 a);北京各地霾日數與主要城市髮展指數之間的相關繫數均超過0.001顯著性水平,隨著城市化而迅速增加的能源消耗和機動車尾氣排放是導緻北京地區灰霾天氣逐漸增多的主要汙染源,汙染源的不均勻分佈是導緻城、郊霾日數差異的主要因素。分析還髮現,城市化導緻的區域氣候差異對跼地灰霾亦有較明顯的影響。伴隨著城市化的快速髮展,城、郊區氣候差異逐漸變大,城市下墊麵粗糙度增加導緻近地麵層風速減小。大城市熱島效應揹景下,更容易齣現較厚的逆溫層,這將阻礙空氣垂直方嚮的對流輸送。此外,城區氣溫持續上升,相對濕度下降,平均風速減小,小風頻率增加,也會阻礙空氣的水平流通,使得城市排放顆粒汙染物的擴散難以擴散,有利于霾日增加。這錶明北京地區城市氣候效應對區域生態環境具有不可忽視的影響。
근년래,수착초대성시/성시군대기회매등복합오염가극,인기인문대구역생태배경여급공공건강문제월래월다적관주。응용북경지구1980-2012년기후자료급동기성시발전통계지표,통계분석료성、교구간매일수적변화특정,병재차기출상탐토료북경성시화급국지기후차이대매일수적영향。분석표명:북경성구매일수요명현다우교구,재2007년이전성、교구참점균유상사적파동증장추세,단성구참매일수증가속솔(약21 d/10 a)요원대우교구참(약7.2 d/10 a);북경각지매일수여주요성시발전지수지간적상관계수균초과0.001현저성수평,수착성시화이신속증가적능원소모화궤동차미기배방시도치북경지구회매천기축점증다적주요오염원,오염원적불균균분포시도치성、교매일수차이적주요인소。분석환발현,성시화도치적구역기후차이대국지회매역유교명현적영향。반수착성시화적쾌속발전,성、교구기후차이축점변대,성시하점면조조도증가도치근지면층풍속감소。대성시열도효응배경하,경용역출현교후적역온층,저장조애공기수직방향적대류수송。차외,성구기온지속상승,상대습도하강,평균풍속감소,소풍빈솔증가,야회조애공기적수평류통,사득성시배방과립오염물적확산난이확산,유리우매일증가。저표명북경지구성시기후효응대구역생태배경구유불가홀시적영향。
Regional ecological environment and public health problems are given more and more focus in recent years as the atmospheric pollution in metropolis or city cycle becoming more serious. In this study, based on the annual meteorological data, hazy days and major urban development indicators during 1980-2012 in Beijing area, the trends of hazy days, major urban development indicators and climate factors trends in Beijing are analyzed, and the effect of local climate change and urbanization process on hazy days is also explored. The results show that a similar increasing trend of hazy days is found in urban and rural area before 2007, but the increasing rate of urban hazy days is larger than that of the rural, with values of 21 d/10 a and 7.2 d/10 a, respectively. The correlation coefficients between haze days and some major urban development indicators in Beijing area have a statistical significance level of 0.001, and this implies that the ever-increasing energy consumption and vehicle emissions are one of the major sources resulting in an increase in haze days in Beijing area. Furthermore, the distinct of hazy days between the urban and rural areas is mainly due to the asymmetric distribution of pollution sources. In addition, we found that the climate difference between the urban and rural caused by urbanization also has an effect on local haze days. The rapid urbanization in Beijing area intensifies the climate difference between the urban and rural. The urban surface wind speed is decreasing due to the increasing roughness of underlying surface, and under the metropolis heat island effect the deep temperature inverse occurs easily and baffles the air vertical convection;moreover, the air horizontal advection is also baffled due to the urban increasing temperature and decreasing humidity and average wind speed. These cause difficulties in the urban contamination diffusion and benefit the increasing of hazy days. Our results imply that the effect of urbanization and urban climate on regional ecological environment cannot be ignored in Beijing.