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根据2015—2018年海南省18个市县32个空气质量监测站O3浓度资料,分析了区域性O3污染(O3-8h浓度超标市县≥3个)时空变化特征,并对造成O3污染的天气系统进行主观分型。结果表明:2015—2018年海南省共有40 d发生了区域性O3污染,发生概率为2.73%。其中2015年和2017年达到了13 d,发生概率为3.56%,2018年为11 d(3.01%),2016年仅为3 d(0.82%)。发生区域性O3污染主要有4种天气类型:冷空气偏西下型、冷空气偏东下型、变暖高压脊型和热带系统型。其中冷空气偏西下型是最主要的天气类型,共出现了14 d,占所有天数的35%,且污染较重。不同天气类型下海南省O3污染表现出不同的分布特征。500 hPa有下沉气流、低层受东北风控制,有相对湿度低值区从中国东部向海南省延伸,地面位于冷高压底部或热带气旋西北侧,温度露点差在5 ℃以上等条件均有利于海南省区域性O3污染天气出现。 相似文献
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人类活动导致大气中温室气体浓度上升,是全球气候变暖的主要原因之一.本文针对已经连续运行13年的AIRS(Atmospheric Infrared Sounder)卫星反演的对流层中层CO2浓度资料,利用地基观测结果对其进行验证,同时结合多种相关资料对我国区域CO2浓度的时空分布及季节变化进行研究.结果显示:北半球30°N—60°N是CO2浓度高值带,低值中心主要出现在15°S—15°N,140°W向东至100°E的低纬地区.地基观测与AIRS卫星反演结果基本一致,年增长率约为1.926 ppmv·a-1.我国区域CO2浓度空间分布上呈现北高南低的非均匀分布特征,4个高值中心分别位于东北地区西南部、内蒙古西部、新疆地区东部和西部,低值中心在云南和西藏地区.我国区域CO2浓度有明显的季节变化特征,最高值出现在春季,冬夏季次之,秋季最低,其季节演变特点与风场的输送、降水量的清除和植被的吸收等密切相关. 相似文献
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An ensemble of satellite measurements, statistic data from government and meteorological diagnosis in regional background site (Haikou, China) has revealed the spatial and temporal characteristics of NO2 and associated synoptic transport patterns over southern China from January 2013 to February 2014. The result shows that: (1) Ozone Monitoring Instrument (OMI) satellite products had a good correlation with observation NO2 in Haikou. The correlation coefficients between Observation NO2 and tropospheric column NO2 and ratio of TroNO2/ TotNO2(tropospheric column NO2/ total column NO2) had all passed the confidence level of 99.9% test. (2) TroNO2 over southern China has an obvious seasonal variation, which is closely coupled with regional meteorology in each season. (3) NO2 concentration in Haikou revealed three pollution periods during December 2013 and January 2014. The variation of NO2 concentration in Haikou is related to the meteorological elements closely. (4) Compared to the monthly mean meteorological fields of the pollution periods, the results indicate that NO2 pollution event in Haikou is directly related to the exogenous transportation from PRD region. An ensemble analysis of meteorological dynamic factors, wind vectors and backward trajectories during the pollution periods further verified this conclusion. 相似文献
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重污染下华南地区小雨和低云量的时空变化趋势特征 总被引:1,自引:0,他引:1
利用华南地区51个站点的逐日小雨降水和低云量等气象资料,采用气候趋势系数、一元回归和相关分析等方法,分析了小雨降水和低云量的年际、季节的长期趋势特征,同时结合华南地区气溶胶光学厚度(AOD)、气溶胶指数和国民生产总值(GDP)等资料进行原因探讨。(1)华南地区小雨日和低云量呈相反的变化趋势(小雨日下降,低云量上升),而且表现为东部高于西部,沿海高于内陆的分布特征。(2)小雨日和低云量的回归系数分别为-4.88 d/(10 a)和1.17%/(10 a)。(3)春季和夏季小雨日变化相对较小,但是对年小雨日贡献较大,而低云量四季均呈现相反的上升趋势。(4)华南地区的两个AOD大值区分别位于广西中部到南部沿海和广东珠三角地区,其中珠三角地区AOD高达0.7以上,气溶胶指数也表现为沿海地区高于内陆地区的分布特征。近27年华南地区的气溶胶指数呈现波动的上升趋势,与同期的小雨日呈负相关关系,而低云量呈正相关关系,近28年华南地区GDP一直处于明显上升趋势,其中以广东省增加最明显。 相似文献
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The number of haze days and daily visibility data for 543 stations in China were used to define the probabilities of four grades of haze days: slight haze(SLH) days; light haze(LIH) days; moderate haze(MOH) days; and severe haze(SEH) days. The change trends of the four grades of haze were investigated and the following results were obtained. The highest probability was obtained for SLH days(95.138%), which showed a decreasing trend over the last54 years with the fastest rate of decrease of-0.903% ·(10 years)-1 and a trend coefficient of-0.699, passing the 99.9%confidence level. The probabilities of LIH and MOH days increased steadily, whereas the probability of SEH days showed a slight downward trend during that period. The increasing probability of SLH days was mainly distributed to the east of 105°E and the south of 42°N and the highest value of the trend coefficient was located in the Pearl River Delta and Yangtze River Delta regions. The increasing probability of LIH days was mainly distributed in eastern China and the southeastern coastal region. The probabilities of MOH and SEH days was similar to the probability of LIH days. An analysis of the four grades of haze days in cities with different sizes suggested that the probability of SLH days in large cities and medium cities clearly decreased during the last 54 years. However, the probabilities of LIH days was 10% and increased steadily. The probability of MOH days showed a clear interdecadal fluctuation and the probability of SEH days showed a weak upward trend. The probability of SLH days in small cities within 0.8° of large or medium cities decreased steadily, but the probability of LIH and MOH days clearly increased, which might be attributed to the impact of large and medium cities. The probability of SLH days in small cities 1.5° from a large or medium city showed an increasing trend and reached 100% after 1990; the probability of the other three grades was small and decreased significantly. 相似文献
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By using the data set of light rain days and low cloud cover at 51 stations in South
China (SC), and the method of linear regression and correlative analysis, we analyze the
spatiotemporal characteristics of the light rain days and low cloud cover including annual
variation and long-term seasonal change. The results are as follows: (1) The trends of light
rain days and low cloud cover over SC are opposite (light rain days tended to decrease and low
cloud cover tended to increase in the past 46 years). The value distributed in east is higher
than that in west, and coastal area higher than inland area. (2) The regression coefficients
of light rain days and low cloud cover during 1960–2005 are 4.88 d/10 years and 1.14%/10
years respectively, which had all passed the 0.001 significance level. (3) Variations of light
rain days are relatively small in spring and summer, but their contributions are larger for
annual value than that of autumn and winter. (4) There are two regions with large values of
aerosol optical depth (AOD), which distribute in central and southern Guangxi and Pearl River
Delta (PRD) of Guangdong, and the value of AOD in PRD is up to 0.7. The aerosol index
distributed in coastal area is higher than in the inland area, which is similar to the light
rain days and low cloud cover over SC. Aerosol indexes in SC kept increasing with fluctuation
during the past 27 years. The GDP of the three provinces in SC increased obviously during the
past 28 years, especially in Guangdong, which exhibited that there is simultaneous correlation
between light rain days with the variables of low cloud cover and release of aerosols over SC
during 1960 to 2005. 相似文献