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干旱区地理 ›› 2016, Vol. 39 ›› Issue (1): 41-46.

• 气候与水文 • 上一篇    下一篇

关中地区低能见度事件变化特征分析

胡琳1, 王琦1, 张文静1, 陈建文1, 曹红丽2   

  1. 1. 陕西省气候中心, 陕西 西安 710014;
    2. 西安市气象局, 陕西 西安 710015
  • 收稿日期:2015-08-09 修回日期:2015-11-15 出版日期:2016-01-25
  • 作者简介:胡琳(1975),女,陕西户县,博士,高工,主要从事环境气象方面的研究工作.Email:hllinbb@126.com
  • 基金资助:

    国家自然科学基金重点项目(41330858);中国气象局公益性行业(气象)科研专项(GYHY201306048)

Variation of low visibility events in Guanzhong of Shaanxi

HU Lin1, WANG Qi1, ZHANG Wen-jing1, CHEN Jian-wen1, CAO Hong li2   

  1. 1 Shaanxi Provincial Climate Center, Xi'an 710014, Shaanxi, China;
    2 Xi'an City Meteorological Bureau, Xi'an 710015, Shaanxi, China
  • Received:2015-08-09 Revised:2015-11-15 Online:2016-01-25

摘要: 以关中城市群为研究区域,选取关中8 个气象站1981-2013 年逐日3 个时次的大气能见度、降水、相对湿度、风速、天气现象等观测资料为研究对象,使用统计方法,分析关中地区低能见度天气时空分布特征,研究影响关中地区低能见度的气象和环境因素,结果表明:1981-2013 年关中地区能见度有下降的趋势,日平均能见度以10~20 km最多,低能见度事件6 月出现最少,12 月最多,冬半年明显高于夏半年,低能见度状况具有明显的延续性.关中西部和中部低能见度日数呈减少趋势而东部增加趋势,关中东、西部城市低能见度日数差异显著减少.雾是造成低能见度事件的主要天气现象,其次为降水和霾.与雾有关的低能见度事件在低能见度总数中占92.8%,雾、霾造成的低能见度事件主要出现在冬季,并以1 月、12 月最多.相对湿度、风速也是重要的影响因素,另外污染物质量浓度是影响能见度水平的另一主要因素.

关键词: 能见度, 低能见度事件, 关中地区, 时空变化特征, 影响因子

Abstract: Selecting Guanzhong City Group,Shaanxi,China as the study area,based on the atmospheric visibility, precipitation,relative humidity,wind speed and weather phenomenon data of 8 climate stations in 3 times of a day during 1981 to 2013,and using the statistical method and partial accumulative anomaly method,this paper discussed the ann-ual,seasonal and daily change law of low visibility events,analyzed the partial multiple periods, less time,temp-oral and spatial distribution features of low visibility weather,and researched the influence of meteorological and environmental factors on low visibility events in Guanzhong area. The results show as follows:( 1)The multi-year aver-age visibility from 1981 to 2013 in Guanzhong area is about 14.1 km and the average annual visibility showed decreasing tendency from 1981 to 2013. The average daily visibility is mainly between 10-20 km,accounting for about 54.6% of the total events. The multi-year average low visibility events is about 110.9 d with the least occu-rrence in June and the most in December,and the multi-year average low visibility events in winter was significa-ntly higher than that in summer. Low visibility is mostly generated in night and early morning. The percentage of low visibility events persisting for more than 2 days is about 83.2%,while for single day,it is only 16.8%.(2)The low visibility events occurred most in Baoji with 139.2d/a,followed by that in Hancheng with 63.2d/a. The diffe-rence between low visibility days in east and west cities has significantly reduced. (3) Frog is the main weather phenomenon that affected the atmospheric visibility,followed by precipitation and haze. Low visibility events related to frog accounted for 91.8% of the total events,and therein,the low visibility events caused by frog and haze together accounted for 26.3%,which occurred mainly in winter,and most in January and December. Besides,low visibility events caused by blowing sand and sand dust storm occurred mainly in the spring.(4)Relative humidity and wind speed also are the important meteorological influencing factors. Low visibility events occur most frequently when daily average relative humidity was between 80% and 90%,and the probability was about 33.3%. When average daily relative humidity was equal to or greater than 70%,the occurrence of low visibility events accounted for more than 75% of the total events. The low visibility events occurred most under static and light wind,which is more than 80% of the total events. In addition,the mass concentrations of SO2,NO2 and PM10 in low visibility events are respectively 52%,32% and 39% higher than that in good visibility events. This research can provide a necessary theoretical basis for accurately forecasting the low visibility events,and provide scientific references for relevant departments to release early warning information and take effective prevention measures for low visibility events.

Key words: visibility, low visibility events, Guanzhong area, temporal and spatial change, influence factors

中图分类号: 

  • P427.2