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1.
The characteristics of surface O3 on clear days at Waliguan Observatory,Lin'an regional station and Longfengshan regional station in China were analyzed in this paper.The three stations belong to Global Atmospheric Watch(GAW)of WMO.There was obvious daily variation on clear days at Lin'an.with maximum(42.9 ppb)and minimum(20.3 ppb)of daily range appearing in spring and summer,respectively.The daily variation was more regular at Lonfengshan than at Lin'an.The maximum(about 27 ppb)appeared in autumn at Longfengshan.There was no obvious daily variation and also daily range was smaller in other seasons except weaker daily variation in summer at Waliguan.But the surface O3 concentration(SOC)in summer was higher than that in winter at Waliguan.The SOC on clear days of summer at Waliguan was over 20 ppb higher than at Longfengshan and Lin'an.The global radiation and NOx concentration were the main factors which control the SOC on clear days at Longfengshan and Lin'an.and played important role in different seasons and areas.The transportation of air flow around the area of Qinghai-Xizang(Tibet)Plateau was the main cause for high SOC and weak daily variation in summer at Waliguan.The similar effect of transportation was obtained at the Mauna Loa Observatory.The distribution characteristics of SOC increasing with height in the troposphere determined the difference of SOC between East China and West China.  相似文献   

2.
中国大气本底条件下不同地区地面臭氧特征   总被引：20，自引：1，他引：20  
分析了晴天和阴天时瓦里关本底台、临安和龙凤山本底站地面 O3浓度的特点。晴天时 ,临安站地面 O3有明显日变化 ,以春季最大 (42 .9× 1 0 - 9) ,夏季最小 (2 0 .3× 1 0 - 9) ;龙凤山站日变化更规则 ,秋季最大 (约 2 7× 1 0 - 9) ;瓦里关本底台除了夏季有微弱日变化外 ,其它季节没有明显的日变化 ,日较差也很小 ,但夏季地面 O3浓度显著高於冬季 ;夏季晴天瓦里关地面O3浓度要比龙凤山、临安高 2 0× 1 0 - 9以上。阴天时 ,临安和龙凤山站除了日变化不很规则和日较差较小外 ,其它大致与晴天相同。阴天时瓦里关不仅没有日变化 ,而且日较差更小 ,但夏季地面 O3仍然高於冬季。太阳总辐射和 NOx 浓度是控制龙凤山和临安晴天和阴天地面O3浓度的决定性因子 ,它在不同季节和地区发挥着重要作用。夏季青藏高原周围地区气流向高原输送作用 ,是形成夏季瓦里关地面 O3高值以及微弱日变化的主要原因。在美国 MaunaLoa基准站也曾观测到类似的输送影响。O3在低对流层随垂直高度增加的分布特征 ,决定了东西部测点地面 O3的差异  相似文献   

3.
The characteristics of surface O_3 on clear days at Waliguan Observatory,Lin'an regionalstation and Longfengshan regional station in China were analyzed in this paper.The three stationsbelong to Global Atmospheric Watch(GAW)of WMO.There was obvious daily variation on cleardays at Lin'an.with maximum(42.9 ppb)and minimum(20.3 ppb)of daily range appearing inspring and summer.respectively.The daily variation was more regular at Lonfengshan than atLin'an.The maximum(about 27 ppb)appeared in autumn at Longfengshan.There was noobvious daily variation and also daily range was smaller in other seasons except weaker dailyvariation in summer at Waliguan.But the surface O_3 concentration(SOC)in summer was higherthan that in winter at Waliguan.The SOC on clear days of summer at Waliguan was over 20 ppbhigher than at Longfengshan and Lin'an.The global radiation and NO_x concentration were themain factors which control the SOC on clear days at Longfengshan and Lin'an.and playedimportant role in different seasons and areas.The transportation of air flow around the area ofQinghai-Xizang(Tibet)Plateau was the main cause for high SOC and weak daily variation insummer at Waliguan.The similar effect of transportation was obtained at the Mauna LoaObservatory.The distribution characteristics of SOC increasing with height in the tropospheredetermined the difference of SOC between East China and West China.  相似文献   

4.
龙凤山大气近地层O3浓度变化及与其它因素的关系   总被引：16，自引：0，他引：16  
研究首次在龙凤山区域大气本底站测得的地面Ｏ３浓度及其变化的资料表明,中国东北农村地面大气Ｏ３浓度总体水平不很高,但在少数特殊的天气条件下,时均浓度可超过国家二级标准。Ｏ３浓度存在明显的季节和日变化,其月平均浓度１９９５年１月最低（２７．５ｐｐｂ）,１９９４年１１月最高（４３．２ｐｐｂ）。Ｏ３日变化幅度夏季的晴天最大（２８ｐｐｂ）,冬季的阴天最小（８ｐｐｂ）。气象要素（尤其是风速、气温和相对湿度等）和ＮＯｘ与地面Ｏ３浓度有较密切的关系。用多变量分析法探讨了地面Ｏ３各指标随气象因子和ＮＯｘ共同变化的规律,并拟合了寒冷和温暖期里与地面Ｏ３日最高浓度、日最低浓度及日变化幅度有关的方程。  相似文献   

5.
Ozone photochemical production and loss in very different environments at Waliguan baseline station and Lin'an background station were simulated by using the measurement data and photochemical box model.The results show that net ozone photochemical production rate is negative,about 0.5 ppb/d,at Waliguan baseline sation,because of very low precursor concentrations.But at Lin'an background station,the net photochemical ozone production is positive,about 2-3 ppb/h.which is very closed with the measurement at Lin'an.That means ozone production was controlled by photochemical reactions at Lin'an background station,because of the higher precursor concentrations.The net destruction rate,at Waliguan Mt.,is not large,so that future increase in anthropogenic emission of reactive nitrogen will lead to larger production rates of steady-state O3 concentration.  相似文献   

6.
中美大气化学联合考察实验结果的初步分析与比较   总被引：1，自引：0，他引：1  
根据临安区域本底站观测资料分析结果得出,中国中纬度地区秋、冬季O3及其前体物NOx等浓度偏高,可以对农作物和地表生态系统产生影响.观测结果表明:近地层大气O3浓度主要决定于地面总辐射量控制下的光化学反应过程;O3的生成受到前体物NOx的控制,但O3与NOx存在着明显的非线性关系.从PEM-WESTA和B的实验及1995年的观测资料表明,O3的生成效率随着NOx浓度的增大而减小.尽管O3的生成速率秋季比冬季的大,但由于秋季较高的NOx抑制了过氧基的生成,因此冬季O3的累积量几乎可以和秋季相比拟.在临安观测的NMHC和NOx的比值比国外同纬度地区测值要大.这说明在临安本底站O3的光化学生成中,NMHC不是控制物种.从而提示我们,在这些季节临安O3光化学产物能够被NOx浓度所控制.中美大气化学联合考察(PEM-WEST-B)实验期间,台湾省的卡盯站SO2的平均浓度为0.29ppb,O3的平均浓度为42.2ppb,可以认为此值为低纬度海岛的本底值.1994年PEM-WEST-B实验期间临安站的观测资料和台湾省的卡盯站资料相比,临安站SO2的浓度约为卡盯站SO2浓度的50倍左右,从而可以看出人类活动对大气本底的显着影响.  相似文献   

7.
The mixing ratios of surface O3 were measured at St. John's College, Agra, an urban and traffic influenced area for the period of 2000–2002. The monthly averaged O3 mixing ratios ranged between 8 to 40 ppb with an annual average of 21 ppb. Strong diurnal and seasonal variations in O3 mixing ratios were observed throughout the year except for monsoon season. The mixing ratios of O3 follow the surface temperature cycle and solar radiation (r = 0.72 and r = 0.65 with temperature and solar radiation, respectively). Concentrations were higher with winds associated with NE and NW direction indicating the impact of pollution sources on surface O3 concentration. Exceedance of ozone critical level was calculated using the AOT 40 index and found to be 840 ppb.h and 2430 ppb.h for summer and winter seasons, respectively. The present O3 exposures are lower than the critical level of O3 and suggest that the present level of O3 does not have any impact on reduction in crop yields.  相似文献   

8.
Surface ozone data from 25 Europeanlow-altitude sites and mountain sites located between79°N and 28°N were studied. The analysiscovered the time period March 1989–February 1993.Average summer and winter O3 concentrations inthe boundary layer over the continent gave rise togradients that were strongest in the north-west tosouth-east direction and west-east direction, respectively. WintertimeO3 ranged from 19 to 27 ppbover the continent, compared to about 32 ppb at thewestern border, while for summer the continentalO3 values ranged between 39 and 56 ppb and theoceanic mixing ratios were around 37 ppb. In the lowerfree troposphere average wintertime O3 mixingratios were around 38 ppb, with only an 8 ppbdifference between 28°N and 79°N. For summerthe average O3 levels decreased from about 55 ppbover Central Europe to 32 ppb at 79°N. Inaddition, O3 and Ox(= O3 + NO2)in polluted and clean air were compared. Theamplitudes of the seasonal ozone variations increasedin the north-west to south-east direction, while thetime of the annual maximum was shifted from spring (atthe northerly sites) to late summer (at sites inAustria and Hungary), which reflected the contributionof photochemical ozone production in the lower partsof the troposphere.  相似文献   

9.
临安与龙凤山辐射数据质量及初步结果比较   总被引：1，自引：1，他引：0       下载免费PDF全文
采用国际通用的辐射数据质量评估方法对2005—2011年浙江临安、黑龙江龙凤山两个区域大气本底站辐射观测资料进行质量评估与比较分析。结果表明:两站辐射数据通过物理可能限制检验与极端罕见限制检验的百分比均超过99.5%,但通过相关要素比较限制检验的百分比上,临安与龙凤山站分别降至97.9%与95.9%;双轴定位追踪太阳出现偏差是造成直接辐射与散射辐射数据精度降低的主要原因。CM21表的热偏移在-5 W·m-2以内,而其进行热偏移订正可以显著提高数据的通过率。对应同一太阳天顶角,临安站晴空总辐射与直接辐射均低于龙凤山站,散射辐射则相反,其原因是临安的大气透明系数较低,大气浑浊度较高。2006—2011年,临安站的大气向下长波辐射呈下降趋势,达到了0.01的显著性水平,且其多年平均值 (363.7±59.3 W·m-2) 显著高于龙凤山站 (274.9±77.6 W·m-2);龙凤山站晴空太阳总辐射呈增加趋势,达到了0.1的显著性水平。  相似文献   

10.
Measurements of surface ozone (O3), nitric oxide (NO), nitrogen dioxide (NO2), oxides of nitrogen (NOx=NO+NO2) and meteorological parameters have been made at Agra (North Central India, 27°10??N, 78°05??E) in post monsoon and winter season. The diurnal variation in O3 concentration shows daytime in situ photochemical production with diurnal maximum in noon hours ranging from 51 to 54 ppb in post monsoon and from 76 to 82 ppb in winter, while minimum (16?C24 ppb) during nighttime and early morning hours. Average 8-h O3 concentration varied from 12.4 to 83.9 ppb. The relationship between meteorological parameters (solar radiation intensity, temperature, relative humidity, wind speed and wind direction) and surface O3 variability was studied using principal component analysis (PCA), multiple linear regression (MLR) and correlation analysis (CA). PCA and MLR of daily mean O3 concentrations on meteorological parameters explain up to 80 % of day to day ozone variability. Correlation with meteorology is strongly emphasized on days having strong solar radiation intensity and longer sunshine time.  相似文献   

11.
对2002年1月1日-2002年12月31日日照市环境监测中心提供的PM10(可吸入颗粒物)日平均浓度资料和对应时段的日照市地面气象资料做了深入的分析,揭示了污染物PM10变化特征及其随气象要素的变化规律。同时分析了主要污染物PM10与地面风速、风向间的相关关系,发现日照市大于等于3级的PM10污染日均出现在1-4月,地面风速对污染物PM10浓度有一定影响,当地面风速超过5m/s时,3级及以上污染日很少出现,当地面风速超过6.5m/s时,随着风速的提高,污染物浓度呈下降趋势。污染物浓度呈明显的季节变化,冬、春季节明显高于夏、秋季节。  相似文献   

12.
在“双碳”目标背景下，从国家层面到地方层面，区域、城市、行业企业都在制定和实施双碳目标行动计划。CO2模拟因其客观性和高时空分辨率等优势，在城市碳排放研究中深受重视。本研究以京津冀地区为研究区域，采用Picarro仪器高精度观测的2019—2020年CO2数据，利用WRF模式进行CO2传输模拟，分析了CO2浓度变化的季节特征，评估了模式在城区中心、城郊及背景3个观测站点的模拟效果，并对边界层高度及化石燃料碳排放等可能影响CO2浓度的因素进行了研究。3个观测站点分别为北京中国科学院大气物理研究所325 m气象塔观测站（北京站）、河北香河观测站（香河站）和上甸子区域本底观测站（上甸子站）。模拟结果表明：上甸子站优于香河站，香河站优于北京站，在冬季尤其明显；CO2浓度的高值区主要分布在城区、电厂和工业区，尤其是唐山、石家庄和邯郸地区，大量交通、工业排放导致CO2浓度明显上升，且高值区的范围在冬季最大；就日平均变化和日变化而言，边界层高度与CO2浓度存在相反变化趋势；3个站点的化石燃料碳排放（FFECO2）与近地面总CO2浓度存在正相关关系，冬春季的相关性高于夏秋季，且FFECO2的占比从大到小依次为北京站、香河站、上甸子站；CO2传输模拟的不确定性存在空间差异和季节变化。  相似文献   

13.
基于典型城市站太原站2018年3月—2019年2月的大气CO2在线观测资料,利用筛分法(Meteorological filtering method, MET)和黑碳示踪法(Black Carbon tracer, BC)进行本底/非本底的筛分,得到了本底浓度的变化特征。结果表明,太原大气CO2浓度季均值冬季最高,夏季最低;不同季节呈“单峰型”日变化特征,日振幅均在26.0×10-6以上;4个季节CO2浓度与地面风速存在显著负相关关系;CO2浓度抬升区域主要受当地工业布局的影响,最大抬升幅度在秋季达17.4×10-6;使用气象筛分法(MET)得到年均本底浓度为(431.4±19.9)×10-6,人为排放等对其影响为23.5×10-6,年振幅比同纬度其它本底站大,为34.5×10-6;黑碳示踪法(BC)得到冬季季均本底浓度为(445.0±22.9)×10-6,比MET筛...  相似文献   

14.
全球闪电活动与对流层上部NO及O3的相关性分析   总被引：1，自引：1，他引：0       下载免费PDF全文
为了解闪电对对流层上部微量气体的贡献,利用全球水资源和气候中心(GHRC)提供的1995年4月—2006年6月的闪电卫星格点资料,以及高层大气研究卫星(UARS)上的卤素掩星试验(HALOE)1991年10月—2005年11月的观测资料,分析了全球闪电与对流层上部NO和O3体积分数的时空分布特征及其相关性。结果表明:全球闪电12、1、2月集中在南半球,6—8月集中在北半球,全球闪电的季节分布与NO、O3类似;NO体积分数在350 h Pa附近达到最大,该高度的南半球NO体积分数变化范围为7×10-12~11×10-12、北半球为3×10-12~17×10-12;450~300 h Pa,北半球夏季O3体积分数呈明显增加趋势,且同一高度上夏季的值比年平均值大25%左右,南半球夏季O3体积分数高于冬季,但差异并不大。结论进一步证明了闪电与对流层上部NO及O3的密切关系,也为研究全球气候变化提供有力证据。  相似文献   

15.
对临安大气本底站2003-2004年冬、夏季二氧化氮(NO2)、二氧化硫(SO2)、臭氧(O3)进行了分析.结果表明:冬季NO2和SO2平均体积分数分别为19.48×10-9和35.74 x10-9,而夏季的平均体积分数分别为4.81×10-9和8.12×10-9,冬季高于夏季;O3在夏季的平均体积分数为33.55×10-9,略高于冬季的25.44×10-9;夜间NO2和SO2体积分数比白天高,并且NO2呈明显的单峰单谷型分布,O3也呈单峰型但峰值出现在白天.NO2、SO2体积分数存在着明显的“假日效应”,假日比非假日低,周五高于假日和非假日;但O3体积分数没有明显的假日效应.降水对SO2有明显的清除作用,但对NO2的清除作用不明显.与风向对比发现,夏季高体积分数的NO2、SO2都受到NW、WNW风的影响,冬季则分别受NE和SW、SSW风的影响;而O3受风向的影响较复杂,与局地光化学反应有关.  相似文献   

16.
Coupled the photosynthesis with transpiration and adjustment of stoma,a dynamic ecological model for simulating the canopy photosynthesis of winter wheat was established by scaling up from the biochemical scale to canopy scale,in which the effects of O3,CO2 and solar spectrum on crop photosynthesis were fully considered.Validation of the model against the data measured with CI-301PS portable photosynthesis analyzer showed that the leaf photosynthesis model passed the correlation significance test and had a fairly high accuracy.Numerical analysis showed that the canopy photosynthesis rate would be reduced by 29% if the O3 concentration increases from 0 ppbv to 200 ppbv,whereas the canopy photosynthesis rate would increase by about 37% while the CO2 concentration increases from 330 ppmv to 660 ppmv,and the canopy photosynthesis rate would be reduced by 27%0 or so under the condition that the spectrum coefficient changed from 0.5 to 0.4.If the O3 concentration reached 200 ppbv at noon on the typical sunny day with higher radiation,the canopy photosynthesis will be reduced slightly in the suburb area where the pollution is serious and the photochemical fog is easy to be formed,contrast with that in the clear region and regardless of the climate change,due to the fact that the positive effect of CO2 on crop photosynthesis can not compensate the negative effect of O3 on crop photosynthesis.The canopy photosynthesis will be reduced by 35% or so than the BASE value at present,when the spectrum of photosynthetic active radiation(PAR) reduces to 0.4 or so.  相似文献   

17.
利用南京地面站点2016—2017年黑碳气溶胶(Black Carbon, BC)和臭氧(O_3)逐小时观测资料,对比分析了不同季节BC与近地面O_3的关系。结果表明,高BC(高于平均值)影响下的O_3质量浓度值明显比低BC(低于平均值)影响下的O_3质量浓度值低,这种抑制作用在秋冬季明显高于春夏季,且BC与O_3的负相关性在秋冬季显著高于春夏季,而PM_(2.5)与O_3的负相关性不显著。利用WRF-Chem模式,对2017年12月个例开展BC反馈效应对O_3影响的数值模拟,结果再次证实BC对O_3存在负反馈影响。其影响机制是:BC可通过抑制边界层发展,使近地面NO_x积聚,从而减少臭氧的化学生成(VOCs控制区);BC可通过抑制边界层垂直湍流交换,减少边界层上部高O_3向下的湍流输送,从而减少近地面O_3;BC可通过减小近地面风速,减少O_3的平流输入,从而减少地面O_3。不同个例的主要控制因子不同。  相似文献   

18.
为了进一步了解青藏高原闪电的产生氮氧化物（LNOx）经由光化学反应对O3浓度变化及夏季O3低谷形成的可能影响,本文利用2005~2013年由OMI卫星得到的对流层NO2垂直浓度柱（NO2 VCD）、O3总浓度柱（TOC）和O3廓线以及星载光学瞬变探测器OTD和闪电成像仪LIS获取的总闪电数资料,对青藏高原和同纬度长江中下游地区的TOC和NO2 VCD月均值时空分布特征、闪电与NO2 VCD的相关性和O3的垂直分布特征及其与LNOx的关系进行了对比分析。结果表明,青藏高原的O3低谷主要出现在夏季和秋季,其TOC值比同纬度长江中下游地区低约10~15 DU（Dobson unit）。青藏高原NO2VCD总体较小,表现为夏高冬低的分布特征。青藏高原夏季O3浓度受南亚高压的影响总体呈减小趋势,但因强雷暴天气导致对流层中上部LNOx浓度升高,并随强上升气流向对流层顶输送,同时通过光化学反应使O3浓度增加,缩小了青藏高原和同纬度地区的O3浓度差,减缓了O3总浓度的下降,抑制了夏季O3低谷的进一步深化。  相似文献   

19.
The impacts of O3 concentration change on rice yields for different lengths of exposure time are studied by means of the OTC-1 open-top chamber.The resuhs indicate that when O3 concentration increased from 50 ppb to 200 ppb during the time period of 20 to 80 days in the experiment,the rice yield was reduced by 6.78% to 33.72%.Two main influencing factors for rice yields are the increased O3 concentration and the extended exposure time.Using a logarithm function to simulate the impacts of O3 concentration on rice yields is better than using a the Weibull function.  相似文献   

20.
利用瓦里关和上甸子大气本底站观测的月平均CO2浓度数据对GOSAT卫星反演的CO2浓度数据进行验证,结果表明GOSAT产品与台站观测数据有较好的一致性.利用2009年6月—2011年5月GOSAT反演的CO2浓度数据,分析了江苏地区CO2浓度的时空变化特征,结果表明:1)975 hPa高度层CO2浓度高于850 hPa高度层,CO2浓度的水平变化要小于垂直变化;2)在季节变化上,CO2浓度冬季最高,夏季最低,这可能与植被光合作用的强弱变化有关;比较前后两年的CO2浓度数据,夏季和秋季的增速较快,冬季和春季的增速较慢;3)在日变化上,发现徐州和南京站02时CO2浓度最高,14时CO2浓度最低,这可能也与植被光合作用的强弱有关.  相似文献   

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