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1.
The total emission control method based on atmospheric environmental capacity is the most effective in air pollution mitigation. The atmospheric environmental capacities of SO2 on representative days over Lanzhou are estimated using the numerical models RAMS, HYPACT and a linear programming model, according to the national ambient air quality standard of China （NAAQSCHN）. The results show that the fields of meteorological elements and SO2 simulated by the models agree reasonably well with observations. The atmospheric environmental capacity of SO2 over Lanzhou is around 111.7 × 10^3 kg d^-1, and in order to meet the air quality level Ⅱ of the NAAQSCHN, SO2 emissions need to be reduced by 20%. 相似文献
2.
Traditional precipitation skill scores are affected by the well-known“double penalty”problem caused by the slight spatial or temporal mismatches between forecasts and observations. The fuzzy (neighborhood) method has been proposed for deterministic simulations and shown some ability to solve this problem. The increasing resolution of ensemble forecasts of precipitation means that they now have similar problems as deterministic forecasts. We developed an ensemble precipitation verification skill score, i.e., the Spatial Continuous Ranked Probability Score (SCRPS), and used it to extend spatial verification from deterministic into ensemble forecasts. The SCRPS is a spatial technique based on the Continuous Ranked Probability Score (CRPS) and the fuzzy method. A fast binomial random variation generator was used to obtain random indexes based on the climatological mean observed frequency, which were then used in the reference score to calculate the skill score of the SCRPS. The verification results obtained using daily forecast products from the ECMWF ensemble forecasts and quantitative precipitation estimation products from the OPERA datasets during June-August 2018 shows that the spatial score is not affected by the number of ensemble forecast members and that a consistent assessment can be obtained. The score can reflect the performance of ensemble forecasts in modeling precipitation and thus can be widely used. 相似文献
3.
Quality Control and Evaluation of the Observed Daily Data in the North American Soil Moisture Database 总被引：1，自引：0，他引：1
Weilin LIAO Dagang WANG Guiling WANG Youlong XIA Xiaoping LIU 《Journal of Meteorological Research》2019,(3):501-518
The North American Soil Moisture Database (NASMD) was initiated in 2011 to assemble and homogenize in situ soil moisture measurements from 32 observational networks in the United States and Canada encompassing more than 1800 stations. Although statistical quality control (QC) procedures have been applied in the NASMD, the soil moisture content tends to be systematically underestimated by in situ sensors in frozen soils, and using a single maximum threshold (i.e., 0.6 m3 m-3) may not be sufficient for robust QC because of the diverse soil textures in North America. In this study, based on the in situ soil porosity and North American Land Data Assimilation System phase 2 (NLDAS-2) Noah soil temperature, the simple automated QC method is revised to supplement the existing QC approach. This revised QC method is first validated based on the assessment at 78 of the Soil Climate Analysis Network (SCAN) stations where the manually checked data are available, and is then applied to all stations in the NASMD to produce a more strict quality-controlled dataset. The results show that the revised automated QC procedure can flag the spurious and erroneous soil moisture measurements for the SCAN stations, especially for those located in high altitudes and latitudes. Relative to station measurements in the original NASMD, the quality-controlled data show a slightly better agreement with the manually checked soil moisture content. It should be noted that this quality-controlled dataset may be over-flagged for some valid soil moisture measurements due to potential errors of the soil temperature and soil porosity data, and validation in this study is limited by the availability of benchmark soil moisture data. The updated QC and additional validation will be desirable to boost confidence in the product when high-quality data become available in the future. 相似文献
4.
Based on the geographical circumstance, climate and the boundary layer meteorology features of the Pearl River Delta, a boundary layer concept model of the Pearl River Delta was built. The concept model consists of four fundamental factors that affect the boundary layer meteorology of the Pearl River Delta and can convincingly explain the reason of the air quality change in the Pearl River Delta. The model can be used to the diffusion capability analysis, the air pollution potential forecasting or haze forecasting, etc. 相似文献
5.
Meteorological conditions have an important impact on changes of vegetation in ecologically fragile karst areas.This study aims to explore a method for quantitative evaluation of these meteorological conditions. We analyzed the changing trend of vegetation during 2000–2018 and the correlations between vegetation changes and various meteorological factors in karst rocky areas of Guangxi Zhuang Autonomous Region, China. Key meteorological factors in vegetation areas with varying degrees of improvement were selected and evaluated at seasonal timescale. A quantitative evaluation model of comprehensive influences of meteorological factors on vegetation was built by using the partial least-square regression(PLS). About 91.45% of the vegetation tended to be improved, while only the rest 8.55% showed a trend of degradation from 2000 to 2018. Areas with evident vegetation improvement were mainly distributed in the middle and northeast, and those with obvious vegetation degradation were scattered. Meteorological factors affecting vegetation were significantly different among the four seasons. Overall, high air humidity, small temperature difference in spring and autumn, and low daily minimum temperature and air pressure were favorable conditions. Low temperature in winter as well as high temperature in summer and autumn were unfavorable conditions. The Climate Vegetation Index(CVI) model was established by PLS using the maximum, minimum, and average temperatures; vapor pressure; rainfall; and air pressure as key meteorological factors. The Enhanced Vegetation Index(EVI) was well fitted by the CVI model, with the average coefficient of determination(r2) and root mean square error(RMSE) of 0.856 and 0.042, respectively. Finally, an assessment model of comprehensive meteorological conditions was built based on the interannual differences in CVI. The meteorological conditions in the study area in 2014 were successfully evaluated by combining the model and selected seasonal key meteorological factors. 相似文献
6.
Calibration and Data Quality Analysis with Mobile C-Band Polarimetric Radar 总被引：4，自引：0，他引：4 
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下载免费PDF全文 LIU Liping HU Zhiqun FANG Wengui GE Runsheng CHEN Xiaohui CAO Junwu 《Acta Meteorologica Sinica》2010,24(4):501-509
A C-band mobile polarimetric radar with simultaneous horizontal and vertical transmission was built in the State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences. It was used in heavy rainfall and typhoon observations in 2008. It is well-known that radar calibration is essential and critical to high quality radar data and products. In this paper, the test and weather signals were used in calibration of reflectivity ZH, differential reflectivity ZDR, and differential phase ΦDP. Noise effects on correlation coefficient ρHV at low signal-noise-ratio (SNR) were analyzed. The polarimetric radar data for a heavy rain and a snow event were inspected to evaluate the performance of the calibration method and radar data quality, and S-band Doppler radar data were used to validate the reflectivity data quality collected by the polarimetric radar. The results show that the polarimetric and S-band Doppler radars have observed comparable reflectivity values and a similar structure of a heavy rainfall case at middle and low levels. The mismatch of two receivers produce obvious ZDR biases, which were verified by the radar data observed at
vertical incidence. The ZDR correction improved the radar data quality. The usage range for ρHV was defined. Application of the calibration method introduced in this paper can reduce the system biases caused by the di?erence of horizontal (H) and vertical (V) channels. After the calibration and correction, the polarimetric parameters observed by the polarimetric radar could be used in further relevant researches. 相似文献
7.
Zhaobin SUN Xiaoling ZHANG Xiujuan ZHAO Xiangao XIA Shiguang MIAO Ziming LI Zhigang CHENG Wei WEN Yixi TANG 《Journal of Meteorological Research》2018,(2)
We used simultaneous measurements of surface PM_(2.5) concentration and vertical profiles of aerosol concentration,temperature, and humidity, together with regional air quality model simulations, to study an episode of aerosol pollution in Beijing from 15 to 19 November 2016. The potential effects of easterly and southerly winds on the surface concentrations and vertical profiles of the PM_(2.5) pollution were investigated. Favorable easterly winds produced strong upward motion and were able to transport the PM_(2.5) pollution at the surface to the upper levels of the atmosphere. The amount of surface PM_(2.5) pollution transported by the easterly winds was determined by the strength and height of the upward motion produced by the easterly winds and the initial height of the upward wind. A greater amount of PM_(2.5) pollution was transported to upper levels of the atmosphere by upward winds with a lower initial height. The pollutants were diluted by easterly winds from clean ocean air masses. The inversion layer was destroyed by the easterly winds and the surface pollutants and warm air masses were then lifted to the upper levels of the atmosphere, where they re-established a multi-layer inversion. This region of inversion was strengthened by the southerly winds, increasing the severity of pollution. A vortex was produced by southerly winds that led to the convergence of air along the Taihang Mountains. Pollutants were transported from southern–central Hebei Province to Beijing in the boundary layer. Warm advection associated with the southerly winds intensified the inversion produced by the easterly winds and a more stable boundary layer was formed. The layer with high PM_(2.5) concentration became dee-per with persistent southerly winds of a certain depth. The polluted air masses then rose over the northern Taihang Mountains to the northern mountainous regions of Hebei Province. 相似文献
8.
The removal of noise and velocity ambiguity and retrieval and verification of horizontal wind
field is a prerequisite to make the best and fullest use of Doppler radar measurements. This approach was
applied to the Doppler radar data collected during August 2005 for a landing typhoon Matsa (0509) in
Yantai, Shangdong Province, and the verified result shows that the quality control for this dataset was
successful. The horizontal wind field was retrieved and then verified by studying the characteristics of the
radar radial velocity and large-scale wind field and the vertical cross section of the radial velocity
determined with the typhoon center as the circle center and comparing it with satellite imagery. The results
show that the meso- and small-scale systems in Matsa and its horizontal and vertical structure could be
clearly retrieved using the dataset collected by single Doppler radar, and a shear or a convergence was
corresponding with a band of severe storm around Matsa. At the same time, the retrieved wind field from
single Doppler radar is proved to be a reliable and high-resolution dataset in analyzing the inner
meso-scale structure of Matsa. It is also proved that the method for removing the velocity ambiguity could
be an effective approach for preliminary quality control of the Doppler radar data, and the VAP method
could also be a reasonable solution for the analysis of mesoscale wind field. 相似文献
9.
Visibility is one of the parameters for indicating air pollution.In this study,visibility variation in Hong Kong during summer and winter is investigated.Visibility in Hong Kong has clear intraseasonal variation.Examination of different environmental parameters suggests that the intraseasonal component dominates the overall circulation anomalies in both summer and winter.Associated with the intraseasonal variation of environmental parameters,obvious variation in visibility impairment is found in both summer and winter.In summer,local visibility and air quality are found to be significantly affected by the(MJO)and the 10–30-day intraseasonal oscillation(ISO)through modulation of associated atmospheric circulations.In winter,the modulation effects appear to be weaker due to the southward shift of the associated convection.The results in this study highlight the importance of the ISO in contributing to the overall variation in visibility in Hong Kong,and provide useful implications for the development of possible mitigation strategies associated with visibility impairment and air pollution in Hong Kong. 相似文献
10.
SENSITIVITY TESTS OF INTERACTION BETWEEN LAND SURFACE PHYSICAL PROCESS AND ATMOSPHERIC BOUNDARY LAYER 总被引：3，自引：0，他引：3
In this paper,an interactive model between land surface physical process and atmosphereboundary layer is established,and is used to simulate the features of soil environmental physics,surface heat fluxes,evaporation from soil and evapotranspiration from vegetation and structures ofatmosphere boundary layer over grassland underlying.The sensitivity experiments are engaged inprimary physics parameters.The results show that this model can obtain reasonable simulation fordiurnal variations of heat balance,soil volumetric water content,resistance of vegetationevaporation,flux of surface moisture,and profiles of turbulent exchange coefficient,turbulentmomentum,potential temperature,and specific humidity.The model developed can be used tostudy the interaction between land surface processes and atmospheric boundary layer in cityregions,and can also be used in the simulation of regional climate incorporating a mesoscalemodel. 相似文献
11.
模糊综合法在城市环境质量评价中的应用 总被引：6，自引：0，他引：6
通过对城市环境质量指标的综合分析,确定了多层次模糊评价法,将其应用于城市空气质量评价中。此法能够将复杂的多层次评价转化为定量评价,从而更合理有效地对区域的大气质量状况加以分析比较。对铜川市2003、2004年度大气环境中SO2、NO2、PM10浓度年的日均值采用模糊综合评价法进行分析,从而评价铜川市的大气环境质量等级。对比分析年度变化趋势,结果客观地反映了城市区域的大气环境状况,从而为改善和治理城市环境提供必要的理论依据。 相似文献
12.
基于模糊综合评判法,依据中国气象局<决策气象服务质量评价办法>,建立了基于多级模糊综合评判法的决策气象服务质量评价模型,并结合实例进行评估试验,给出试验分析和结论. 相似文献
13.
基于模糊综合评判法,依据中国气象局《决策气象服务质量评价办法》,建立了基于多级模糊综合评判法的决策气象服务质量评价模型,并结合实例进行评估试验,给出试验分析和结论。 相似文献
14.
将模糊综合评价及马尔可夫链同时运用到空气质量的评价中,可克服大气环境系统所固有的模糊性及随机性。通过1994—1998年芜湖市大气环境监测数据计算表明:不仅预测结果准确,而且由于应用了模糊数学方法,使得结果较为可信,且整个过程计算简单,是一种较适合的方法。 相似文献
15.
将模糊综合评价及马尔可夫链同时运用到空气质量的评价中,可克服大气环境系统所固有的模糊性及随机性。通过1994—1998年芜湖市大气环境监测数据计算表明：不仅预测结果准确,而且由于应用了模糊数学方法,使得结果较为可信,且整个过程计算简单,是一种较适合的方法。 相似文献
16.
应用模糊数学法综合评价淮安市大气环境质量 总被引：2，自引：1，他引：1
运用模糊数学方法,选用SO2、NO2、PM10作为评价因子,参照大气环境质量标准,通过计算污染因子权重分配系数和隶属度对淮安市总体大气环境质量给出客观的评价。综合评判结果表明,淮安总体大气环境质量为中度污染(三级),且空气质量在逐年恶化。用模糊概念进行推理,经过运算得出的综合评价结果与一般评价方法相比更接近客观。 相似文献
17.
多级模糊综合评判法在气象服务保障能力评估中的应用 总被引：12，自引：6，他引：6
根据模糊集的基本理论,借助模糊综合评判方法,给出了气象服务保障能力评估指标体系,并运用多级模糊综合评判法对气象服务保障能力进行了评估试验,为气象服务保障能力的评估提供了一种更科学和客观的方法。 相似文献
18.
近年来,我国大气污染问题凸显,大气环境越来越受到重视,对大气环境影响评价的要求也越来越高,因而,引入一些新的方法能更全面和细致地评价大气环境影响。本文基于法规模式体系,介绍在实际环评工作中用到的四种方法,包括足迹(footprint)函数法、四维通量法、源解析法和动画演示法,对其原理和适用范围进行了描述。这些方法以大气导则推荐的模式系统为基础,从不同视角深入地描述大气污染物的运动和分布特征,在大气环评工作中可根据实际问题的需要选择合适的方法进行大气环境影响的分析与评估研究。 相似文献
19.
通过对项目风险进行综合分析、审定,确立一种气象科研项目的立项风险评估指标及体系的准则;从风险角度出发,构建出一组多级指标的项目风险评估指标体系;采用定性和定量相结合的方法,提出一种基于模糊理论的风险评估体系和模型,对科研项目的立项进行综合评估,给出评估意见,给决策提供指导意见;同时,提出一种气象科研项目绩效考核及推广方法. 相似文献
20.
以某苯加氢精制工程为例,探讨了焦化行业环境风险评价方法;利用该项目所在地近3 a地面常规气象观测资料,分析了当地的污染气象特征;采用风险识别、源项分析、后果计算、风险评价等环境风险评价技术方法,筛选出主要风险因子并进行风险预测,采用多烟团模式并考虑气象因素进行风险计算。结果表明：污染事故发生后,苯类物质的地面浓度最大值为3 214 mg/m^3,位于距离事故发生源WNW方向约50 m处超标1 339倍,由此可知近距离污染严重;高浓度污染物主要集中在污染源附近,随着距离的延长,污染物浓度不断向下风向扩散,超标范围在6 km内。利用简化分析法,定量给出此项工程的最大可信事故风险值为7.6×10^-6/a,小于化工行业风险值8.33×10^-5/a,此工程风险值水平与同行业比较在可接受的范围内。 相似文献