检索结果-南通市图书馆

Comparison of Two Air Pollution Episodes over Northeast China in Winter 2016/17 Using Ground-Based Lidar

在线全文

学校读者我要写书评

暂无评论

Journal of meteorological Research 2018年第2期32卷 313-323页

作者： Yanjun MA Hujia ZHAO Yunsheng DONG Huizheng CHE Xiaoxiao LI Ye HONG Xiaolan LI Hongbin YANG Yuche LIU Yangfeng WANG Ningwei LIU Cuiyan SUN Institute of Atmospheric Environment China Meteorological Administration Shenyang 110016 Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 State Key Laboratory of Severe Weather/Institute of Atmospheric Composition Chinese Academy of Meteorological Sciences Beijing 100081 Dalian Municipal meteorological observatory Dalian 116001 Jinan Center of Aviation Control Jinan 250107

This study analyzes and compares aerosol properties and meteorological conditions during two air pollution episodes in 19–22（E1） and 25–26（E2） December 2016 in Northeast China. The visibility, particulate matter（PM） mass concentration, and surface meteorological observations were examined, together with the planetary boundary layer（PBL） properties and vertical profiles of aerosol extinction coefficient and volume depolarization ratio that were measured by a ground-based lidar in Shenyang of Liaoning Province, China during December 2016–January *** suggest that the low PBL height led to poor pollution dilution in E1, while the high PBL accompanied by low visibility in E2 might have been due to cross-regional and vertical air transmission. The PM mass concentration decreased as the PBL height increased in E1 while these two variables were positively correlated in E2. The enhanced winds in E2 diffused the pollutants and contributed largely to the aerosol transport. Strong temperature inversion in E1 resulted in increased PM2.5 and PM10 concentrations, and the winds in E2 favoured the southwesterly transport of aerosols from the North China Plain into the region surrounding Shenyang. The large extinction coefficient was partially attributed to the local pollution under the low PBL with high ground-surface PM mass concentrations in E1,whereas the cross-regional transport of aerosols within a high PBL and the low PM mass concentration near the ground in E2 were associated with severe aerosol extinction at high altitudes. These results may facilitate better understanding of the vertical distribution of aerosol properties during winter pollution events in Northeast China.

关键词： aerosol pollution ground-based lidar Northeast China

Plumb line deflection varied with time obtained by repeated gravimetry

在线全文

学校读者我要写书评

暂无评论

Acta Seismologica Sinica(English Edition) 2001年第1期14卷 66-71,117页

作者：李辉付广裕李正心 Institute of Seismology China Seismological Bureau Wuhan China Shanghai observatory China Astronomical Observatory Station Shanghai China

In this paper, the plumb line deflection varied with time (PLV) are calculated with the Vening-Meinesz formula for Xiaguan and beijing point based on the 28 and 39 campaigns of gravimetry at the local gravity networks in the Western Yunnan Earthquake Prediction Experiment Area and the North China, respectively. Based on the results, we conclude that: (1) the maximum of PLV is under 0.1 double prime and amplitudes of interannual variation are under 0.02 double prime . (2) PLV can be determined with the reliability of 0.01 double prime by the modeling based on the precession of repeated gravimetry. This implies that repeated gravimetry could be used to determine the PLV. (3) There exist some common and different characteristics for the different places and different components. It may provide a new approach for the study on the local or global geodynamic by using repeated gravimetry.

关键词： gravity plumb line deflection

同方期刊数据库

The weakening effect of urbanization on tropical cyclone surface winds:An observational study for Shanghai

在线全文

学校读者我要写书评

暂无评论

Tropical Cyclone Research and Review 2024年第1期13卷 15-23页

作者： Lechuan Zhang Hui Yu Xiangyu Ao Shengming Tang Chinese Academy of meteorological Sciences BeijingChina Shanghai Typhoon Institute China Meteorological AdministrationShanghaiChina

The observation-reanalysis difference method(OMR)and wind proﬁleﬁtting method were used to analyze the inﬂuence urbanization has on the near-surface wind speed in Shanghai during tropical cyclone *** data used include daily wind speed data from the Shanghai meteorological observatory station collected from 1991 to 2020,hourly wind speed data from 100 m high wind towers from 2017 to 2019,and reanalysis data that covered the same *** results indicated that during tropical cyclone occurrence,the wind speed of the OMR in the central urban region was signiﬁcantly lower than that in the suburban area,and the OMR declined more obviously over the year,down to-8 m/s in *** leads to the increase of average wind weakening rate to be higher than the maximum wind weakening rate,causing the maximum weakening rate of the central urban region to the average wind over 80%,while maximum wind speed was less than 80%.The weakening rate of both the average and maximum wind speeds during tropical cyclone impacts is greater than the rate that the annual average wind speed was reduced.A logarithmic variation was visible in the wind proﬁle of the island station during tropical cyclone occurrence,with an average friction velocity U*of 0.9389 m/s and an average rough length Z0 of 0.4915 *** wind speed during tropical cyclone events was higher than the three-year average wind speed within each *** suburban stations show a linear variation,and every hundred meters of height results in an increase of 5–6 m/s in the wind speed change *** 100 m of altitude,the wind speed in the suburban region is reduced by approximately 40%.

关键词： Urbanization Tropical cyclone Shanghai Wind speed

ANALYSIS OF THE EFFECT OF 3DVAR AND ENSRF DIRECT ASSIMILATION OF RADAR DATA ON THE FORECAST OF A HEAVY RAINFALL EVENT

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Tropical Meteorology 2016年第3期22卷 413-425页

作者：刘寅何光鑫刘佳伟赵虹燕成玉 Jiangsu meteorological Observation Center Nanjing 210009 China Jiangsu Institute of meteorological Sciences Nanjing 210009 China Center for Data Assimilation Research and Application Nanjing University of Information Science & Technology Nanjing 210044 China Luhe meteorological bureau Nanjing 211599 China Qinhuangdao Municipal meteorological observatory Qinhuangdao 066000 China

The present study designs experiments on the direct assimilation of radial velocity and reflectivity data collected by an S-band Doppler weather radar(CINRAD WSR-98D) at the Hefei station and the reanalysis data produced by the United States National Centers for Environmental Prediction using the Weather Research and Forecasting(WRF) model,the WRF model with a three-dimensional variational(3DVAR) data assimilation system and the WRF model with an ensemble square root filter(EnSRF) data assimilation *** addition,the present study analyzes a Meiyu front heavy rainfall process that occurred in the Yangtze-Huaihe River Basin from July 4 to July 5,2003,through numerical *** results show the following.(1) The assimilation of the radar radial velocity data can increase the perturbations in the low-altitude atmosphere over the heavy rainfall region,enhance the convective activities and reduce excessive simulated precipitation.(2) The 3DVAR assimilation method significantly adjusts the horizontal wind *** assimilation of the reflectivity data improves the microphysical quantities and dynamic fields in the *** addition,the assimilation of the radial velocity and reflectivity data can better adjust the wind fields and improve the intensity and location of the simulated radar echo bands.(3) The EnSRF assimilation method can assimilate more small-scale wind field information into the *** assimilation of the reflectivity data alone can relatively accurately forecast the rainfall *** addition,the assimilation of the radial velocity and reflectivity data can improve the location of the simulated radar echo bands.(4) The use of the 3DVAR and EnSRF assimilation methods to assimilate the radar radial velocity and reflectivity data can improve the forecast of precipitation,rain-band areal coverage and the center location and intensity of precipitation.

关键词： assimilation radar data heavy rainfall forecast numerical simulation

Analysis of the Positive Effect from the Typhoon Saomai to the Hydrothermal Environment of Shanghai

在线全文

学校读者我要写书评

暂无评论

Journal of Geoscience and Environment Protection 2017年第8期5卷 221-234页

作者： Rong Guo Yongyuan Weng Shanghai Central meteorological observatory Shanghai China Shanghai meteorological bureau Shanghai China

Northwestern Pacific is the only ocean which has the most typhoon formation. The study of typhoon has far reaching significance today. Typhoon can relieve drought and make temperature drop substantially. Even we were suffering continuous high temperature in summer, the temperature would decrease immediately accompanied with typhoon. By using MODIS and weather station data to calculate the vegetation index, we analyze the drought characteristics of Shanghai during Saomai period, so that we can show the changes from the two aspects of the vegetation growth and the surface temperature. On the other hand, through the relative humidity data of Typhoon Saomai, we can find that the vegetation index and the relative humidity have been increased significantly. Typhoon rain also has its beneficial agricultural production side. It can lift the drought or ease the drought. It also provides abundant water resources for the growth of crops. In addition, the typhoon for the adjustment of the Earth’s heat, is contributed to maintain heat balance. Therefore, the typhoon to bring the changes in hydrothermal environment on the objective assessment of its impact and timely use of typhoon resources are of great significance.

关键词： Typhoon Shanghai Saomai Hydrothermal Environment Vegetation Index

Observation and Numerical Simulation of Cloud Physical Processes Associated with Torrential Rain of the Meiyu Front

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2003年第1期20卷 77-96页

作者：王鹏云杨静 Chinese Academy of meteorological Sciences Beijing

Cloud micro-physical structures in a precipitation system associated with the Meiyu front are observed using the balloon-borne Precipitation Particle Image Sensor at Baoshan observatory station, Shanghai during June and July 1999. The vertical distributions of various cloud particle size, number density, and mass density are retrieved from the observations. Analyses of observations show that ice-phase particles (ice crystals, graupel, snowflakes, and frozen drops) often exist in the cloud of torrential rain associated with the Meiyu front. Among the various particles, ice crystals and graupel are the most numerous, but graupel and snow have the highest mass density. Ice-phase particles coexist with liquid water droplets near the 0°C level. The graupel is similarly distributed with height as the ice crystals. Raindrops below the 0°C level are mainly from melted grauple, snowflakes and frozen drops. They may further grow larger by coalescence with smaller ones as they fall from the cloud base. Numerical simulations using the non-hydrostatic meso-scale model MM5 with the Reisner graupel explicit moisture scheme confirm the main observational results. Rain water at the lower level is mainly generated from the melting of snow and graupel falling from the upper level where snow and graupel are generated and grown from collection with cloud and rain water. Thus the mixed-phase cloud process, in which ice phase coexists and interacts with liquid phase (cloud and rain drops), plays the most important role in the formation and development of heavy convective rainfall in the Meiyu frontal system.

关键词： videosonde cloud micro-physical structure Meiyu front precipitation meso-scale numerical simulation

Advancing index-based climate risk assessment to facilitate adaptation planning:Application in Shanghai and Shenzhen,China

在线全文

学校读者我要写书评

暂无评论

Advances in Climate Change Research 2022年第3期13卷 432-442页

作者： Zhan TIAN Xin-Yang LYU Huan ZOU Hong-Long YANG Laixiang SUN Maria Sunyer PINYA Qing-Chen CHAO Ai-Qing FENG Ben SMITH School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Shanghai Institute of Technology Shanghai 200235China School of Finance and Management SOAS University of LondonLondon WC1H 0XGUK Shenzhen National Climate observatory of meteorological bureau of Shenzhen Municipality Shenzhen 518040China Department of Geographical Sciences University of MarylandCollege Park MD 20742USA Arup Group Limited London W1T 4BQUK National Climate Center China Meteorological AdministrationBeijing 10081China China meteorological Administration Climate Studies Key Laboratory Beijing 100081China

One of the key issues in climate risk management is to develop climate resilient infrastructure so as to ensure safety and sustainability of urban functioning systems as well as mitigate the adverse impacts associated with increasing climate ***,conventional methods of assessing risks do not fully address the interaction of various subsystems within the city system and are unable to consolidate diverse opinions of various stakeholders on their assessments of sector-specific risks posed by climate *** address this gap,this study advances an integrated-systems-analysis tool-Climate Risk Assessment of Infrastructure Tool(CRAIT),and applies it to analyze and compare the extent of risk factor exposure and vulnerability over time across five critical urban infrastructure sectors in Shanghai and Shenzhen,two cities that have distinctive geo-climate profiles and histories of infrastructure *** results show significantly higher level of variation between the two cities in terms of vulnerability levels than that of *** specifically,the sectors of critical buildings,water,energy,and information&communication in Shenzhen have significantly higher vulnerability levels than Shanghai in both the 2000s and the *** further discussed the vulnerability levels of subsystems in each sector and proposed twelve potential adaptation options for the roads system based on four sets of criteria:technical feasibility,flexibility,co-benefits,and policy *** application of CRAIT is bound to be a knowledge co-production process with the local experts and *** knowledge co-production process highlights the importance of management advancements and nature-based green solutions in managing climate change risk in the future though differences are observed across the efficacy categories due to the geographical and meteorological conditions in the two *** study demonstrates that this knowledge co-creation process is valuable

关键词： Climate risk assessment Megacities Resilient urban infrastructures Subsystem Knowledge co-creation process China

Inversion of single-station teleseismic P-wave polarization data for the velocity structure of beijing area

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2001年第3期44卷 256-265页

作者：刘福田胡戈王怀军陈晓非游庆瑜 Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Lamont-Doherty observatory and Department of Geological Sciences Columbia University New York USA Department of Geophysics Peking University Beijing China

Broadband three-component seismic data recorded by beijingstation (BJI) of CDSN were used to calculate P-wave polarization of teleseismic events. These polarization data were then used in the inversion for the underground structure around the beijing station, especially for the details of velocity discontinuities. The result shows that a conspicuous low velocity zone exists in the crust on the west of the station, which is in good agreement with previous studies. It proves the theory that polarization data could be applied to inversion for velocity structures, especially for boundaries with large velocity gradient. It also demonstrates the feasibility of velocity structure inversion with polarization data from high-quality broadband data recorded by a single station. Therefore, travel-times and polarization data can be jointly used to study velocity structure. Polarization data are more suitable for delineating the boundary of velocity anomalies. Moreover, if the polarization method is combined with receiver function method to fully exploit their complementarity, it is possible to obtain the lateral velocity variation around the station as well as the detailed vertical variation below the station.

关键词： P-wave polarization velocity structure beijing station

Activity of cold vortex in northeastern China and its connection with the characteristics of precipitation and circulation during 1960-2012

在线全文

学校读者我要写书评

暂无评论

Journal of Geographical Sciences 2015年第12期25卷 1423-1438页

作者： LIU Gang FENG Guolin QIN Yulin CAO Ling YAO Hongwei LIU Ziqi Atmospheric Sciences Academy of Lanzhou University Lanzhou 730000 China meteorological observatory of Jilin Province Changchun 130062 China National Climate Centre CMA Beijing 100081 China Jilin Province meteorological Service Center Changchun 130062 China meteorological bureau of Nong'an County Nong'an 130200 Jilin China

Based on the daily reanalysis data released by NCEP/NCAR and the daily precipi- tation of 753 Chinese stations from May to August during the period of 1960 to 2012, the statistical characteristics of the cold vortex in northeastern China were analyzed. In addition, the strength index, which described the characteristics of the vortex consistently and fre- quently, and the geographical distribution were given by continuous anomalies of circulation. Based on this index, the activity routines of the cold vortex, characteristics of atmospheric circulation, and their effects on precipitation in northeastern China were analyzed. The results show that： the activities of the cold vortex exhibit remarkable features of annual and interde- cadal oscillation, and the vortex high frequency and its characteristics of atmospheric circula- tion are described more accurately by the strength index of the cold vortex, which shows a high correspondence with the vortex precipitation during early summer and midsummer in the northeast. In strong （weak） vortex years, the general circulation in the middle and high lati- tudes of Eurasia is to the advantage （disadvantage） of the formation, development and maintenance of the cold vortex, thus it is easy （difficult） to form the circulation which is bene- ficial to transmit vapor from south to north during the period of July to August. Blocking over the Ural Mountains prevails （does not prevail） in early summer, and blocking over the Sea of Okhotsk prevails （does not prevail） in midsummer. Areas where the subtropical high is too small （large） and moves toward the north too late （early） are better （worse） for the mainte- nance of the cold vortex in northeastern China.

关键词： northeast cold vortex index of strength circulation subtropical high