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天津冬季两个典型污染过程高浓度无机气溶胶成因及来源分析

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环境科学 2024年第5期45卷 2581-2595页

作者：卢苗苗韩素芹刘可欣唐晓孔磊丁净樊文雁王自发天津市环境气象中心天津300074 中国气象局‐南开大学大气环境与健康研究联合实验室天津300074 南开大学环境科学与工程学院天津市城市交通污染防治研究重点实验室天津300071 中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室北京100029 中国科学院大气物理研究所国际气候与环境科学中心北京100029 中国科学院大学地球与行星科学学院北京100049

无机气溶胶是天津冬季霾天出现的主要成分,研究挑选了2020年1月污染天中两个典型的高浓度无机气溶胶(SIA)过程(CASE1和CASE2),利用观测数据和耦合了在线污染物来源追踪方法的大气化学传输模式NAQPMS综合探究了气象要素、区域输送和化学... 详细信息

无机气溶胶是天津冬季霾天出现的主要成分,研究挑选了2020年1月污染天中两个典型的高浓度无机气溶胶(SIA)过程(CASE1和CASE2),利用观测数据和耦合了在线污染物来源追踪方法的大气化学传输模式NAQPMS综合探究了气象要素、区域输送和化学过程的影响.两个过程的ρ(SIA)均值分别为76.8μg·m^(−3)和66.0μg·m^(−3),硝酸盐浓度高于硫酸盐和铵盐,均为硝酸盐为主导的污染过程.气象条件影响了无机气溶胶的生成,CASE1过程ρ(SIA)>80μg·m^(−3)对应的温度和相对湿度区间分别是[−6℃,0℃]、[2℃,4℃]和[50%,60%]、[80%,100%];CASE2过程对应的温度和相对湿度区间分别是[2℃,4℃]和[60%,70%].外来源对CASE1和CASE2过程SIA的平均贡献率为62.3%和22.1%,分别为区域传输主导和局地生成主导过程.CASE1本地排放对硝酸盐和硫酸盐的贡献分别为16.2μg·m^(−3)和8.2μg·m^(−3),均高于外来源的贡献(31.7μg·m^(−3)和8.8μg·m^(−3));CASE2过程本地排放对硝酸盐和硫酸盐的贡献分别为29.3μg·m^(−3)和25.1μg·m^(−3),而外来源的贡献为8.1μg·m^(−3)和9.4μg·m^(−3).这表明CASE1本地生成和外来源输送贡献造成硝酸盐高于硫酸盐浓度,而CASE2仅本地源造成硝酸盐浓度高于硫酸盐.两个污染过程气相氧化反应是无机气溶胶生成的首要来源,贡献率分别为48.9%和57.8%;非均相反应也是重要过程,对SIA的贡献率分别为48.1%和42.2%;液相反应的影响小.

关键词：无机气溶胶气象因素区域传输化学过程天津

基于气象水文水动力耦合模型的流域尺度洪水预报方法:以北江流域为例

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科学技术与工程 2024年第11期24卷 4397-4408页

作者：韩赟希张昕王自法周良辰朱龙祥河南大学土木建筑学院开封475004 深圳防灾减灾技术研究院深圳518003 中震科建(广东)防灾减灾研究院韶关512026 中国地震局工程力学研究所哈尔滨150080

针对中小流域目前径流和淹没预报难度较大且精度偏低的问题,以北江流域为研究对象,构建降雨径流-洪水淹没模型。在非耦合情况下,基于WRF-Hydro模式构建北江流域水文模型,通过对主要参数率定,优化了WRF-Hydro水文模型,模拟了流域的产流... 详细信息

针对中小流域目前径流和淹没预报难度较大且精度偏低的问题,以北江流域为研究对象,构建降雨径流-洪水淹没模型。在非耦合情况下,基于WRF-Hydro模式构建北江流域水文模型,通过对主要参数率定,优化了WRF-Hydro水文模型,模拟了流域的产流、汇流等水循环关键要素。在耦合情况下,将WRF-Hydro模式模拟的径流过程作为CaMa-Flood模型的边界条件,从而实现对整个流域的洪水淹没模拟。研究结果表明:在经过参数率定的WRF-Hydro水文模型中,针对验证期的5场典型洪水事件,皮尔逊相关系数均高于0.8,纳什效率系数在0.52~0.71,在预报期的三个洪水事件中,洪峰的平均误差为22.2%。在水文水动力模型耦合后,能够准确地捕捉洪水淹没与降雨强度、洪水流量变化之间的关系,进而提供洪水发生后洪泛区的淹没深度和范围等关键信息。本文构建的降雨径流-洪水淹没模型能够适用于地形复杂、降雨时空分布不均匀的北江流域,为类似半湿润流域的洪水预报提供了有益参考,同时也为水文水动力模型耦合的研究奠定了基础。

关键词：北江流域 WRF-Hydro水文模型 CaMa-Flood水动力模型洪水预报洪水淹没模拟

Discrete vortices on anisotropic lattices

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Frontiers of physics 2015年第4期10卷 55-60页

作者： Gui-Hua Chen Hong-Cheng wang zi-fa Chen Department of Electronic Engineering Dongguan University of Technology Dongguan 523808 China

We consider the effects of anisotropy on two types of localized states with topological charges equal to 1 in two-dimensional nonlinear lattices, nsing the discrete nonlinear SchrSdinger equation as a paradigm model. We find that on-site-centered vortices with different propagation constants are not globally stable, and that upper and lower boundaries of the propagation constant exist. The region between these two boundaries is the domain outside of which the on-site-centered vortices are unstable. This region decreases in size as the anisotropy parameter is gradually increased. We also consider off-site-centered vortices on anisotropic lattices, which are unstable on this lattice type and either transform into stable quadrupoles or collapse. We find that the transformation of off-site- centered vortices into quadrupoles, which occurs on anisotropic lattices, cannot occur on isotropic lattices. In the quadrupole case, a propagation-constant region also exists, outside of which the localized states cannot stably exist. The influence of anisotropy on this region is almost identical to its effects on the on-site-centered vortex case.

关键词： anisotropy discrete vortex quadrupole localized state

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我国东部山地针阔混交林碳通量特征分析

中国环境科学 2024年第6期44卷 3492-3501页

作者：孙彦坤张胤洲姚维杰叶京张峻搏潘小乐刘兰忠王自发程雪玲东北农业大学资源与环境学院黑龙江哈尔滨150030 中国科学院大气物理研究所大气边界层物理与大气化学国家重点实验室北京100029 中国科学院大气物理研究所大气边界层顶生态环境上黄观测站浙江金华321203

以浙江省金华市武义县大毛尖山为研究区域,开展复杂山地森林生态系统碳汇能力的观测研究,并利用涡动相关法在2022年6月~2023年5月进行观测,经过数据质量控制和质量评价分析,得到42%的优质CO_(2)通量数据.结果表明,大毛尖山周边以针阔混... 详细信息

以浙江省金华市武义县大毛尖山为研究区域,开展复杂山地森林生态系统碳汇能力的观测研究,并利用涡动相关法在2022年6月~2023年5月进行观测,经过数据质量控制和质量评价分析,得到42%的优质CO_(2)通量数据.结果表明,大毛尖山周边以针阔混交林为主,能量闭合度为0.89,能够很好的代表站点通量情况.CO_(2)通量在日尺度上均表现为U型变化,范围为-1.20~0.89mgCO_(2)/(m^(2)·s).四季碳汇能力强弱依次为,夏季、春季、秋季、冬季;各月份净生态系统碳交换量(NEE)均为负值,整体表现为碳汇.CO_(2)通量与气象因子中的空气温度呈负相关,相对湿度和平均风速正相关,夜间因呼吸作用产生的CO_(2)通量与土壤温度正相关.本研究初步解释了大毛尖山森林生态系统的碳汇特征.

关键词： CO_(2)通量涡动相关法(EC) 净生态系统碳交换量(NEE) 森林生态系统复杂地形

Ammonium Variational Trends and the Ammonia Neutralization Effect on Acid Rain over East Asia

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Atmospheric and Oceanic Science Letters 2010年第2期3卷 120-126页

作者： GAO Chao wang zi-fa Enagnon A. GBAGUIDI State Key Laboratory of Atmospheric Boundary Layer Physics＇ and Atmospheric Chemistry/Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The distribution and variations of ammonium and the ammonia neutralization effect on acid rain were examined in East Asia during the period of 2000 05 using observed wet deposition data from the Acid Deposition Monitoring Network in East Asia (EANET).Observational trends show a high proportion of NH 4 + in the total cations,with a six-year mean proportion of over 20% for continental and inland *** concentrations and deposition of NH 4 + were higher in western China and Vietnam than in other *** annual variations in NH 4 + concentration were smooth in most of the regions,except for southern China and Vietnam,where the NH 4 + concentrations increased,and western China,where the NH 4 + concentrations *** neutralization factors (NFs) of NH 4 + indicate that ammonia has a great neutralization capability toward acid rain,including for the regions with low NH 4 + concentrations,such as *** NFs were high in summer,with no obvious discrepancies between the northern and southern ***,the correlation coefficients between NH 4 + concentrations and rain pH values imply that the ammonia neutralization effects on the pH values were distinct only at southern China and southern Japan *** neutralization of precipitation by ammonia was estimated by comparing the discrepancies between the observed pH values and the pH values calculated without ammonia consuming the H + in NH 4 +.The results demonstrate that ammonia may increase annual mean pH values by 0.4 0.7 in southern China and by 0.15 0.25 in southern Japan.

关键词： acid rain ammonium neutralization effect

Chemical characterization of submicron particles during typical air pollution episodes in spring over Beijing

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Atmospheric and Oceanic Science Letters 2016年第4期9卷 255-262页

作者： YANG Ting SUN Ye-Le ZHANG Wei wang zi-fa wang Xi-Quan State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Aviation Meteorological Center of China BeijingChina

Beijing experienced a long-lasting pollution episode in April 2012. Here, the authors characterize the sources and evolution processes of the pollution, with a focus on a haze and a dust episode that occurred during 15-30 April. All submicron aerosol species （PM1） showed substantial increases during the haze episode （HE）, with nitrate being the largest, contributing on average 32.2% of the non-refractory PM;（NR-PM1） mass （maximum： -42.0%）, which was different from other seasons. Secondary inorganic aerosol （SIA） species （55.1 ± 23.8 lag m-3; SIA = nitrate, ammonium, sulfate） played enhanced roles in the haze formation, accounting for 66.5% of the total NR-PM1 mass. In contrast to the HE, organics exhibited their highest levels （8.9 ± 5.4 lag m-3） among the NR-PM aerosol species during the dust episode, accounting for 64.0% on average. SIAs exhibited low concentration levels （4.6 ± 4.2 μg m-3） during the dust episode, contributing only 34.0% to the total NR-PM1 mass. This study suggests that air quality improvement strategies should be designed according to aerosol particle characteristics and formation mechanisms.

关键词： Particulate matter haze pollution nitrate secondaryinorganic aerosols, Beijing

Spatial Source Contributions Identification of Acid Rain over the Yangtze River Delta Using a Variety of Methods

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Atmospheric and Oceanic Science Letters 2015年第6期8卷 397-402页

作者： GE Bao-Zhu LIU Ying CHEN Huan-Sheng PAN Xiao-Le wang zi-fa State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Laboratory for Climate Studies National Climate Center China Meteorological Administration Research institute for applied mechanics/Kyushu university

The source-receptor relation of wet deposition has been a continuous issue in studies of regional environmental pollution over the past two *** the absence of direct observational evidence,the problem is difficult to solve—a topic of broad international debate since the turn of the present *** the present study,a variety of methods focused on the sources of the wet deposition of acidic substances,like sulfate and nitrate,were used to investigate the precipitation chemistry over the Yangtze River Delta(YRD)during ***-trajectory analysis associated with the observation data and a source tracing method coupled with the Nested Air Quality Prediction Modeling System(NAQPMS)are proved to be effective methods for investigating the sources of wet deposition over the *** among the back-trajectory,footprint,and NAQPMS results shows good consistency,both qualitatively and *** most important contributor to acidic substances in the YRD,as well as heavy acid rain over the region,is the anthropogenic pollution from East China,which accounts for more than 70%.

关键词： acid rain source identification Yangtze River Delt

Observation of nocturnal low-level wind shear and particulate matter in urban Beijing using a Doppler wind lidar

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Atmospheric and Oceanic Science Letters 2017年第6期10卷 411-417页

作者： CHEN Yong AN Jun-Ling LIN Jian SUN Ye-Le wang Xi-Quan wang zi-fa DUAN Jing State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Xiamen China College of Earth Science University of the Chinese Academy of Sciences Beijing China Chinese Academy of Meteorological Sciences Beijing China

A field experiment of nocturnal mountain wind and corresponding particulate matter （PM） evolution under weak synoptic forcing at five sites within urban Beijing was conducted using a moving Doppler wind lidar and a fixed tower. Clear wind shear and zero-horizontal-wind zones at 40-320 m above the ground with a delay of 1.5 h were found at two sites between 20 km from north to south urban Beijing. The wind speed and height of the low-level jet at the north urban Beijing site were greater than those at the east urban Beijing site. The average horizontal distribution of low-level PM at 240 m was similar to the ground-level PM at night. The PM2.s （aerodynamic diameter ≤2.5 μm） accumulation center showed no abrupt changes with a shift in wind direction until the northerly wind jet arrived.

关键词： Mountain-plain wind windshear wind lidar

Trends of surface PM_(2.5) over Beijing–Tianjin–Hebei in 2013–2015 and their causes: emission controls vs. meteorological conditions

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Atmospheric and Oceanic Science Letters 2017年第4期10卷 276-283页

作者： WEI Ying LI Jie wang zi-fa CHEN Huan-Sheng WU Qi-Zhong LI Jian-Jun wang Yuan-Lin wang Wei State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences College of Global Change and Earth System Science Beijing Normal University China National Environmental Monitoring Centre

The PM2.5 （particulate matter with a diameter of less than 2.5 μm） trends during the period 2013- 2015, in 13 cities over the Beijing-Tianjin-Hebei region, and their causes, were investigated using observations at 75 stations and a regional air quality model. It was found that annual PM2.5 in this region experienced a significant decrease in 2014 and 2015, compared with 2013. PM2.s in 2015 almost met the target on air quality in the 13th Five-Year Plan （2012-2017）. In southern cities （e.g. Xingtai, Handan, Shijiazhuang, and Cangzhou）, this PM2.5 decreasing trend was caused by both meteorological conditions and regional emission controls in 2014 and 2015. Contributions from regional emission controls were more significant than meteorological conditions. In Tianjin and Langfang, the impact of regional emission controls was partly offset by the meteorological conditions in 2014. In 2015, meteorological conditions turned favorable for a PM2.s decrease, but emission controls were still the dominant cause. Compared with polluted cities in Hebei and Tianjin, the decreasing trend in Beijing was small （4% and 9% in 2014 and 2015）.This reflects the competition between adverse meteorological conditions and emission controls. In northern cities （Tangshan, Qinhuangdao, and Zhangjiakou）, regional emission controls dominated the PM2.5 decreasing trend in 2014 and 2015, although they were partly offset by meteorological conditions. In all cities during the heating season in 2015, a more significant decreasing trend of high PM2.5 from emission controls was found than low and middle PM2.5. This indicates that air pollution controls are developing towards refined management （e.g. the Heavy Air Pollution Emergency Response Program） in this region.

关键词： PM2.5 trend meteorologicalconditions regional emissioncontrols NAQPMS