检索结果-南通市图书馆

Characteristics of air quality in Tianjin during the Spring Festival period of 2015

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Atmospheric and Oceanic Science Letters 2016年第1期9卷 15-21页

作者： TANG Miao Jl Dong-Sheng GAO Wen-Kang YU Zhong-Wang CHEN Kui cao Wan Tianjin Environment Monitoring Center Tianjin 300191China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100083China University of Chinese academy of sciences Beijing 100049China Tianjin Environmental Protection Bureau Tianjin 300191China

To better understand the characteristics of air quality and the relationship between the chemical composition evolution and source variation,an intensive atmospheric campaign was conducted in Tianjin,a megacity of the North china Plain,from 10 February to 6 March *** were 20 days exceeding the threshold value of secondary Chinese Ambient Air Quality Standards for PM2.5(75 μg m-3,daily average over 24 h)during the study *** air pollution episodes were selected for *** the pre-holiday pollution episode,NH^+_4,NO^-_3,and SO^(2-)_4 were more abundant,indicating that air pollution was caused by motor vehicle exhaust emissions and coal consumption under unfavorable meteorological *** Chinese Lunar New Year's Eve,widespread use of fireworks resulted in extremely high aerosol *** displays caused increases in K+ and also enrichment of SO^(2-)_4 relative to NO^-_*** holiday pollution episode was caused by regional transport,characterized by abundant SO^(2-)_4 and NH^+_*** addition,the aging processes of the particles from fireworks discharge played an important role in the formation of NO-3and SO^(2-)_*** Lantern Festival episode was characterized by a transition from the enrichment of K+ to secondary inorganic ions(NO^-_3,SO^(2-)_4,and NH^+_4).The results of this study are useful for a detailed understanding of the variation in atmospheric compositions and sources caused by anthropogenic activity,and highlight the importance of controlling intensive fireworks discharge.

关键词： tianjin water-soluble ions fireworks organic carbon elemental carbon

Unusual Evolution of the Multiple Eyewall Cycles in Super Typhoon Hinnamnor(2022)

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Journal of meteorological Research 2023年第4期37卷 431-440页

作者： Hui WANG Yubin YU Dajun ZHAO Tzu-Hsiung YEN Hongxiong XU Qian WANG Zhiqiang cao State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081 china meteorological Administration Training Centre Beijing 100081 Shanghai Typhoon Institute China Meteorological AdministrationShanghai 200030 Department of Atmospheric sciences “National”Taiwan UniversityTaipei 10617 National meteorological Centre China Meteorological AdministrationBeijing 100081 Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites National Satellite Meteorological Center/National Center for Space WeatherChina Meteorological AdministrationBeijing 100081

Hinnamnor was the first super typhoon in the western North Pacific basin in *** had several prominent characteristics,such as rapid intensification after its formation,three eyewall cycles,and a sudden recurvature of its *** on multi-source observational and reanalysis datasets,two secondary eyewall formation(SEF)cycles occurred during Super Typhoon Hinnamnor’s *** first SEF happened near the time when Hinnamnor achieved its maximum intensity,and it seems that its internal dynamics dominated the SEF process after the development of shear-induced asymmetric spiral *** merger of a tropical depression with Hinnamnor led to a continuous increase in both its inner-core size and outer-core circulation,causing generation of the second *** is inferred that the external and internal dynamics worked together during the second SEF *** concentric eyewall structure maintained for approximately 84 h under the moderate vertical wind ***,unique changes in intensity accompanied the two structural changes.

关键词： concentric eyewall secondary eyewall formation tropical cyclone intensity change

南襄盆地春节期间一次典型的重污染过程分析--以襄阳市为例

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环保科技 2024年第2期30卷 20-27页

作者：杨如春王振楠曹世凯孙天宝蔡舰中科宇图科技股份有限公司北京100101 襄阳市大气污染防治管理中心湖北襄阳441011 襄阳职业技术学院湖北襄阳441050

基于襄阳市2023年1月环境监测数据,结合气溶胶激光雷达、后向轨迹模式(HYSPLIT)等技术手段,对襄阳市春节期间一次重污染过程的污染因子变化情况、气象因素以及传输来源等进行了研究分析。结果表明:本次污染过程变化特征由偏沙尘型-偏烟... 详细信息

基于襄阳市2023年1月环境监测数据,结合气溶胶激光雷达、后向轨迹模式(HYSPLIT)等技术手段,对襄阳市春节期间一次重污染过程的污染因子变化情况、气象因素以及传输来源等进行了研究分析。结果表明:本次污染过程变化特征由偏沙尘型-偏烟花型-偏二次型-偏沙尘型转变。弱高压前部、高空粗颗粒物输送是第一阶段PM_(10)升高的主要原因,污染气团主要来源于新疆、甘肃、内蒙古区域,途经宁夏、陕西、河南等地。第二阶段主要由不利气象、区域环境、污染传输及烟花爆竹燃放等综合影响,造成PM_(2.5)重污染过程,主要受湖北局地气团影响。第三阶段污染由霾转变为浮尘影响再逐渐消散,前期冷空气携带上游污染物影响襄阳,后随高压南下,天气现象逐渐转为受浮尘影响,随浮尘过境及粗颗粒物沉降,空气质量好转,污染气团主要来自新疆、甘肃、内蒙古区域,途经宁夏、陕西等地到达襄阳市区。

关键词：襄阳市重污染污染传输沙尘霾气象因子

Population,urbanization and economic scenarios over the Belt and Road region under the Shared Socioeconomic Pathways

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Journal of Geographical sciences 2020年第1期30卷 68-84页

作者： JING Cheng TAO Hui JIANG Tong WANG Yanjun ZHAI Jianqing cao Lige SU Buda State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyCASUrumqi 830011China Collaborative Innovation Center on Forecast and Evaluation of meteorological Disasters/Institute for Disaster Risk Management/School of Geographical Science Nanjing University of Information Science&TechnologyNanjing Jiangsu 210044China National Climate Center China Meteorological AdministrationBeijing 100081China University of Chinese academy of sciences Beijing 100049China

The countries throughout the Belt and Road region account for more than 60%of the world’s population and half of the global *** changes in this area will have significant influences on the global economic growth,industrial structure and resource *** this study,the proportion of the urban population to the total population and the gross domestic product were used to represent the levels of urbanization and economic development,*** population,urbanization and economic levels of the Belt and Road countries for 2020-2050 were projected under the framework of the IPCC's shared socioeconomic pathways(SSPs),and the following conclusions are drawn.(1)The population,urbanization and economic levels in the Belt and Road region will likely increase under all five *** population will increase by 2%-8%/10a during 2020-2050 and reach 5.0-6.0 billion in ***,the urbanization rate will increase by 1.4%-7.5%/10a and reach 49%-75%.The GDP will increase by 17%-34%/10a and reach 134-243 trillion USD.(2)Large differences will appear under different *** SSP1 and SSP5 pathways demonstrate relatively high urbanization and economic levels,but the population size is comparatively smaller;SSP3 shows the opposite ***,the economy develops slowly under SSP4,but it has a relatively high urbanization level,while SSP2 exhibits an intermediate trend.(3)In 2050,the population will increase relative to 2016 in most countries,and population size in the fastest growing country in Central Asia and the Middle East countries will be more than *** will develop rapidly in South Asia,West Asia and Central Asia,and will increase by more than 150%in the fastest growing *** economy will grow fastest in South Asia,Southeast Asia and West Asia,and increase by more than 10 times in some counties with rapid economic development.

关键词： population urbanization and economic scenarios Shared Socioeconomic Pathways 2020-2050 the Belt and Road region

基于病菌孢子捕捉和real-time PCR技术的田间空气中小麦白粉病菌孢子动态监测及病情估计模型研究

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植物保护 2024年第2期50卷 49-56,72页

作者：王奥霖商昭月张美惠王贵胡小平徐飞孙振宇曹世勤刘伟范洁茹周益林中国农业科学院植物保护研究所植物病虫害综合治理全国重点实验室北京100193 西北农林科技大学植物保护学院作物抗逆与高效生产全国重点实验室杨凌712100 河南省农业科学院植物保护研究所农业农村部华北南部作物有害生物综合治理重点实验室郑州450002 甘肃省农业科学院植物保护研究所兰州730070 新疆农业大学农学院农林有害生物监测与安全防控重点实验室乌鲁木齐830052

利用Burkard定容式孢子捕捉器结合real-time PCR定量技术,分别对种植高抗、中感和高感白粉病小麦品种的田间空气中白粉病菌分生孢子浓度进行监测,结果表明,real-time PCR定量与传统的显微观察计数两种方法测得的孢子浓度呈显著正相关(P... 详细信息

利用Burkard定容式孢子捕捉器结合real-time PCR定量技术,分别对种植高抗、中感和高感白粉病小麦品种的田间空气中白粉病菌分生孢子浓度进行监测,结果表明,real-time PCR定量与传统的显微观察计数两种方法测得的孢子浓度呈显著正相关(P≤0.01),且两种病菌孢子计数方法在同一抗性品种上监测到的孢子浓度动态相近。此外,两种方法测得的孢子浓度与各气象因子的相关性分析结果一致,空气中的白粉病菌孢子浓度主要与空气相对湿度显著正相关。在此基础上,利用两种方法测定的田间空气中白粉病菌孢子浓度分别建立了基于累积孢子浓度的田间病情估计模型。分析发现,基于两种孢子浓度测定方法建立的病情估计模型间无显著性差异,表明real-time PCR定量技术测定的孢子浓度在构建白粉病病情估计模型上具有一定可行性。该结果为real-time PCR定量技术与病菌孢子捕捉技术相结合用于小麦白粉病的监测和预测提供理论依据。

关键词：小麦白粉病病菌孢子捕捉实时荧光定量PCR 病原菌监测病情估计模型

基于Landsat 8和机器学习的塔城地区草地地上生物量估测模型

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湖北农业科学 2024年第8期63卷 66-71页

作者：杨延晓曹姗姗李全胜张鲜花孙伟新疆农业大学计算机与信息工程学院乌鲁木齐830052 新疆农业大学草业学院乌鲁木齐830052 中国农业科学院农业信息研究所北京100081

以新疆塔城地区为研究区,利用植被指数、气象数据、地形数据作为自变量,结合研究区样地实测生物量数据,分析并比较K近邻回归(KNN)、多元线性回归(MLR)、梯度提升决策树(GBDT)和随机森林回归(RF)和极端梯度提升(XGBoost)5种机器学习模型... 详细信息

以新疆塔城地区为研究区,利用植被指数、气象数据、地形数据作为自变量,结合研究区样地实测生物量数据,分析并比较K近邻回归(KNN)、多元线性回归(MLR)、梯度提升决策树(GBDT)和随机森林回归(RF)和极端梯度提升(XGBoost)5种机器学习模型,进而分析并比较采用投票回归器(Voting regressor)和堆叠(Stacking)方法构建的2种集成学习模型的估测精度。结果表明,基于Stacking集成学习模型性能最优,R^(2)达0.764,RMSE和MAE分别为23.29 g/m^(2)和16.8 g/m^(2),进而利用最优模型进行草地地上生物量(Above ground biomass,AGB)反演制图。

关键词：草地地上生物量 Landsat 8 遥感影像机器学习估测模型新疆塔城地区

维普期刊数据库博看期刊

Linear trends in mean and extreme temperature in Xiongan New Area, china

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Atmospheric and Oceanic Science Letters 2018年第3期11卷 246-254页

作者： QIAN Cheng cao Li-Juan CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese academy of Science BeijingChina National meteorological Information Center China Meteorological AdministrationBeijingChina

On 1 April 2017 china established Xiongan New Area in Hebei Province, which was described as ‘a strategy crucial for a millennium to come＇. A point of interest for the public is to be aware of the historical climate change in this new area; however, results from previous global-scale or largerregional-scale averages provide relatively limited information because of the distinct regional differences in climate change. This study analyzes the changes in mean and extreme temperature in this area, based on homogenized daily temperature data for the period 1960–2016. The results show a significant warming in the indices of annual, summer, and winter mean temperature（Tmean）, maximum temperature（Tmax）, and minimum temperature（Tmin）. The linear rate of annual Tmean is 0.34 °C/decade. Temperatures on the hottest day, the warmest night, the coldest day, and the coldest night, every year, all show increasing trends, with the trends in the two nighttime-related indices being significant. An increasing occurrence of warm days, warm nights, hot days, and tropical nights, but a decreasing occurrence of cold days, cold nights, icing days, and frost days, are found, all of which are significant, except for the occurrences of hot days and icing days. A significant extension of the length of the thermal growing season is also found. The magnitudes of change in most of the temperature indices in Xiongan New Area are larger than those of the adjacent Jing-Jin-Ji and North china regional mean. These results could provide valuable information for policymakers, city planners, engineers, and migrants to this new area.

关键词： Xiongan New Area climatechange linear trend meantemperature extremetemperature

Evolution of planetary boundary layer under different weather conditions,and its impact on aerosol concentrations

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Particuology 2013年第1期11卷 34-40页

作者： Jiannong Quan Yang Gao Qiang Zhang Xuexi Tie Junji cao Suqin Han Junwang Meng Pengfei Chen Delong Zhao beijing Weather Modification Office Institude of Urban Meteorology CMA Key Laboratory of Aerosol SKLLQGInstitute of Earth EnvironmentChinese Academy of Sciences National Center for Atmospheric Research BoulderUSA Key Laboratory of Aerosol SKLLQGInstitute of Earth Environment.Chinese Academy of Sciences Tianjin Institute of meteorological sciences

A field experiment was conducted in Tianjin, china from September 9-30, 2010, focused on the evolution of Planetary Boundary Layer （PBL） and its impact on surface air pollutants. The experiment used three remote sensing instruments, wind profile radar （WPR）, microwave radiometer （MWR） and micro-pulse lidar （MPL）, to detect the vertical profiles of winds, temperature, and aerosol backscattering coefficient and to measure the vertical profiles of surface pollutants （aerosol, CO, SO2, NOx）, and also collected sonic anemometers data from a 255-m meteorological tower. Based on these measurements, the evolution of the PBL was estimated. The averaged PBL height was about 1000-1300 m during noon/afternoon-time, and 200-300 m during night-time. The PBL height and the aerosol concentrations were anti-correlated during clear and haze conditions. The averaged maximum PBL heights were 1.08 and 1.70 km while the averaged aerosol concentrations were 52 and 17 μg/m＆3 under haze and clear sky conditions, respectively, The influence of aerosols and clouds on solar radiation was observed based on sonic anemometers data collected from the 255-m meteorological tower. The heat flux was found significantly decreased by haze （heavy pollution） or cloud, which tended to depress the development of PBL, while the repressed structure of PBL further weakened the diffusion of pollutants, leading to heavy pollution. This possible positive feedback cycle （more aerosols→lower PBL height → more aerosols） would induce an acceleration process for heavy ground pollution in megacities.

关键词： Planetary boundary layer (PBL) Interaction between the PBL and aerosols

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广州白云机场雷暴大风的气候特征和环境参数

广东气象 2024年第4期46卷 29-33页

作者：张有洋郭智亮季思含曹正刘阳高聪晖中国民用航空中南地区空中交通管理局广东广州510000 中国民用航空华北地区空中交通管理局北京100000 福建省气象台福建福州35000

基于2005—2021年广州白云机场气象观测报文数据和清远探空站探空数据,采用线性趋势分析、合成分析等方法,分析广州白云机场雷暴大风的气候特征及环境参数。结果表明:广州白云机场年平均雷暴大风日数为10.43 d,并呈缓慢增加的趋势,季节... 详细信息

基于2005—2021年广州白云机场气象观测报文数据和清远探空站探空数据,采用线性趋势分析、合成分析等方法,分析广州白云机场雷暴大风的气候特征及环境参数。结果表明:广州白云机场年平均雷暴大风日数为10.43 d,并呈缓慢增加的趋势,季节分布呈单波峰型,主要分布在3—9月,占雷暴大风日数总数的97.6%。历史风速极大值为42 m/s,大风的风速强度主要在15~19 m/s区间内,雷暴大风主要出现在午后至前半夜的时段。影响雷暴大风的主要天气系统为低压槽和切变线;其次是气旋型、西太副热带高压型和锋面型。最大抬升指数介于-1至-4.5℃;湿对流有效位能中位值介于1130~1395 J/kg;850与500 hPa温度差介于21.2~23.7℃;对流抑制能量值介于0.875~69.15 J/kg;0~3 km风矢量差介于0.3~3.1 m/s;湿层厚度介于2302.3~5250.5 m,易发生雷暴大风天气。

关键词：气候学雷暴大风物理量环境参数广州白云机场