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Impact of the Complex Terrain in Beijing on Formation of Low-Level Jets

Journal of Meteorological Research 2024年第1期38卷 138-150页

作者： Li’ao ZHOU Chenggang WANG shiguang miao Ju LI School of Atmospheric Physics Nanjing University of Information Science&TechnologyNanjing 210044 Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089 Key Laboratory of Urban Meteorology China Meteorological AdministrationBeijing 100089

This study investigated how the Taihang Mountains and the Yanshan Mountains affect low-level jets(LLJs)in the Beijing area,based on conventional radiosonde observations from Nanjiao Observatory(2016–2017)and high-resolution Weather Research and Forecasting–Advanced Research WRF(WRF-ARW)model simulations.Analysis of radiosonde observations indicated that LLJs in the study area are mainly from the southwest and northwest directions,with occurrence frequency of 44.6%and 33.0%,respectively.Southwest(northwest)LLJs are aligned parallel(perpendicular)to the orientation of the Taihang Mountain Range.Terrain sensitivity experiments using the WRF-ARW model were then conducted to examine the effects of terrain forcing on the northwest and southwest LLJs,with adopted terrain heights of 100%and 50%.The results showed that for northwest LLJs,reduction in the elevation of the Taihang Mountain Range led to weakening of jet intensity by approximately 20%and reduction in jet maximum height by approximately 250 m;lowering the Yanshan Mountain Range had minor influence on the northwest LLJs,with only a 5.2%reduction in intensity and no substantial change in jet maximum height.For southwest LLJs,reduction in the elevation of both the Taihang and Yanshan Mountain ranges resulted in minor changes in the intensity and height of the jets.Further analysis revealed that the topography in the Beijing area could modulate the height and intensity of the stable layer by altering the inversion structure within the boundary layer.The LLJs can develop rapidly within the stable layer,and both the location and the scale of the jet core exhibited reasonable agreement with the extent of the stable layer.

关键词： low-level jets(LLJs) mesoscale numerical simulation terrain forcing

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Community-Level Practice Checklists for Health Protection During Cold Spells in China

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China CDC weekly 2024年第5期6卷 83-87页

作者： Jing Shang Mengzhen Zhao Zhao Liu Xiya Zhang shiguang miao Ishaq D.Sulaymon Wenjia Cai Institute of Urban Meteorology CMABeijingChina School of Management and Economics Beijing Institute of TechnologyBeijingChina School of Airport Economics and Management Beijing Institute of Economics and ManagementBeijingChina Department of Earth System Science Tsinghua UniversityBeijingChina Sand and Dust Storm Warning Regional Center National Center for MeteorologyJeddahSaudi Arabia Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing CityJiangsu ProvinceChina

Communities play a crucial role in protecting the health of vulnerable populations such as the elderly,low-income groups,and high-risk individuals during cold spells.However,current strategies for responding to cold spells primarily consist of programmatic policies that lack practicality,specificity,and detailed implementation guidelines for community workers.Therefore,this study aims to identify and analyze the challenges faced by communities in responding to cold spells,review international experiences,and develop a set of practical checklists for community-level health protection.These checklists will assist community workers and volunteers in effectively preparing for,responding to,and recovering from cold spells.

关键词： preparing income primarily

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Design of digital calibration based on variable step size of sub-binary SAR ADC

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 62-71页

作者： Liu Wei Zhao Yanke Shang shiguang School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

Addressing the impact of capacitor mismatch on the conversion accuracy of successive approximation register analog-to-digital converter(SAR ADC),a 12-bit 1 MS/s sub-binary SAR ADC designed using variable step size digital calibration was proposed.The least mean square(LMS)calibration algorithm was employed with a ramp signal used as the calibration input.Weight errors,extracted under injected disturbances,underwent iterative training to optimize weight values.To address the trade-off between conversion accuracy and speed caused by a fixed step size,a novel variable step size algorithm tailored for SAR ADC calibration was proposed.The core circuit and layout of the SAR ADC were implemented using the Taiwan Semiconductor Manufacturing Company(TSMC)0.35μm complementary metal-oxide-semiconductor(CMOS)commercial process.Simulation of the SAR ADC calibration algorithm was conducted using Simulink,demonstrating quick convergence and meeting conversion accuracy requirements compared to fixed step size simulation.The results indicated that the convergence speed of the LMS digital calibration algorithm with variable step size was approximately eight times faster than that with a fixed step size,also yielding a lower mean square error(MSE).After calibration,the simulation results for the SAR ADC exhibited an effective number of bit(ENOB)of 11.79 bit and a signal-to-noise and distortion ratio(SNDR)of 72.72 dB,signifying a notable enhancement in the SAR ADC performance.

关键词： successive approximation register analog-to-digital converter(SAR ADC) variable step size digital calibration disturbance technique

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Effect of tillage state of paddy soils with heavy metal pollution on the nosZ gene of N_(2)O reductase

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Journal of Environmental Sciences 2024年第3期137卷 469-477页

作者： Liping Jiang shiguang Liu Shanyun Wang Libo Sun Guibing Zhu Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China School of Environmental and Civil Engineering Jiangnan UniversityWuxi 214122China

Paddy soils are an important source of atmospheric nitrous oxide(N_(2)O).However,numerous studies have focused on N_(2)O production during the soil tillage period,neglecting the N_(2)O production during the dry fallow period.In this study,we conducted an incubation experiment using the acetylene inhibition technique to investigate N_(2)O emission and reduction rates of paddy soil profiles(0-1 m)from Guangdong Province and Jinlin Province in China,with different heavy-metal pollution levels.The abundance and community structures of denitrifying bacteria were determined via quantitative-PCR and Illumina MiSeq sequencing of nosZ,nirK,and nirS genes.Our results showed that the potential N_(2)O emission rate,N_(2)O production rate,and denitrification rate have decreased with increasing soil vertical depth and heavy-metal pollution.More importantly,we found that the functional gene type of N_(2)O reductase switched with the tillage state of paddy soils,which cladeⅡnos Z genes were the dominant gene during the tillage period,while cladeⅠnos Z genes were the dominant gene during the dry fallow period.The heavy-metal pollution has less effect on the niche differentiation of the nos Z gene.The N_(2)O emission rate was significantly regulated by the genus Bradyhizobium,which contains both N_(2)O reductase and nitrite reductase genes.Our findings suggests that the nos Z gene of N_(2)O reductase can significantly impact the N_(2)O emission from paddy soils.

关键词： Pappy soils N_(2)O reductase nosZ gene Heavy-metal pollution

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Interfacial oxidized Pd species dominate catalytic hydrogenation of polar unsaturated bonds

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Nano Research 2024年第1期17卷 228-234页

作者： Pengyao You Shaoqi Zhan Pengpeng Ruan Ruixuan Qin shiguang Mo Yazhou Zhang Kunlong Liu Lansun Zheng Nanfeng Zheng State Key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materialsand Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Department of Chemistry BMCUppsala UniversityBMC Box 576Uppsala S-75123Sweden Department of Chemistry University of OxfordOxford OX13QZUK

The determination of catalytically active sites is crucial for the design of efficient and stable catalysts toward desired reactions.However,the complexity of supported noble metal catalysts has led to controversy over the locations of catalytically active sites(e.g.,metal,support,and metal/support interface).Here we develop a structurally controllable catalyst system(Pd/SBA-15)to reveal the catalytic active sites for the selective hydrogenation of ketones to alcohol using acetophenone hydrogenation as model reaction.Systematic investigations demonstrated that unsupported Pd nanocrystals have no catalytic activity for acetophenone hydrogenation.However,oxidized Pd species were catalytically highly active for acetophenone hydrogenation.The catalytic activity decreased with the decreased oxidation state of Pd.This work provides insights into the hydrogenation mechanism of ketones but also other unsaturated compounds containing polar bonds,e.g.,nitrobenzene,N-benzylidene-benzylamine,and carbon dioxide.

关键词： oxidized Pd metal/oxide interface constant particle size Pd/SBA-15 acetophenone hydrogenation

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Enhanced modeling of latent heat flux from urban surfaces in the Noah/single-layer urban canopy coupled model

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Science China Earth Sciences 2014年第10期57卷 2408-2416页

作者： miao shiguang CHEN Fei Institute of Urban Meteorology China Meteorological Administration National Center for Atmospheric Research

The numerical modeling of the impacts of urban buildings in mesoscale meteorological models has gradually improved in recent years. Correctly representing the latent heat flux from urban surfaces is a key issue in urban land-atmosphere coupling studies but is a common weakness in current urban canopy models. Using the surface energy balance data at a height of 140 m from a 325 m meteorological tower in Beijing, we conducted a 1-year continuous off-line simulation by using a coupled land surface model and a single-layer urban canopy model and found that this model has a relatively large systematic error for simulated latent heat flux. To improve the numerical method for modeling latent heat flux from urban surfaces, we combined observational analysis and urban land surface model to derive an oasis effect coefficient for urban green areas; to develop a temporal variation formula for water availability in urban impervious surfaces; and to specify a diurnal profile and the maximum values of anthropogenic latent heat release for four seasons. These results are directly incorporated into the urban land surface model to improve model performance. In addition, this method serves as a reference for studies in other urban areas.

关键词：城市建筑表面模型潜热通量耦合模式建模单层冠层数值计算方法

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Localization and validation of an urbanized high-resolution land data assimilation system(u-HRLDAS)

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Science China Earth Sciences 2013年第6期56卷 1071-1078页

作者： MENG ChunLei ZHANG ChaoLin miao shiguang CHEN Fei Institute of Urban Meteorology China Meteorological Administration Department of Earth Sciences National Natural Science Foundation of China National Center for Atmospheric Research BoulderColorado 80301USA

This paper uses an urbanized high-resolution land data assimilation system(u-HRLDAS) to parameterize the urban land surface characteristics.The u-HRLDAS model is localized and developed in order to satisfy the need of the weather forecast in Beijing,China.The remote sensing data used to localize and drive u-HRLDAS include the soil type data and MODIS retrieved leaf area index(LAI) data.The evaporation and water depth for impervious surface in urban area are developed to improve the simulation of u-HRLDAS.The result of the urban weather forecast is used for the comparison based on the rapid update cycle system at Beijing Meteorological Bureau(BJ-RUC) without coupled with u-HRLDAS.The land surface temperature,land surface fluxes,and first layer soil moisture in several single sites and urban Beijing region by BJ-RUC are compared with u-HRLDAS after localization and development.The off-line simulation results indicate that compared with BJ-RUC,after the localization and development,u-HRLDAS can improve the simulation of land surface parameters and fluxes definitely.

关键词：陆面数据同化系统高分辨率城市化本地化北京市气象局验证土地天气预测

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Analysis of observations on the urban surface energy balance in Beijing

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Science China Earth Sciences 2012年第11期55卷 1881-1890页

作者： miao shiguang DOU JunXia CHEN Fei LI Ju LI AiGuo Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China National Center for Atmospheric Research BoulderCO 80307-3000USA Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

1 年(20092010 ) 大小从在一个 325-m 塔的三垂直的层位于闹市区北京的传感器获得的城市的表面精力平衡(SEB ) 被分析。结果显示出那：(1 ) 从 325-m 塔的大小代表位于半潮湿的温暖适度的大陆人季风气候地区的城市的 SEB 特征。在典型... 详细信息

1 年(20092010 ) 大小从在一个 325-m 塔的三垂直的层位于闹市区北京的传感器获得的城市的表面精力平衡(SEB ) 被分析。结果显示出那：(1 ) 从 325-m 塔的大小代表位于半潮湿的温暖适度的大陆人季风气候地区的城市的 SEB 特征。在典型热、多雨的夏天，感冒和干燥冬季，测量鲍恩比率在冬季在夏天和最大值是最小的。在 140 m 测量春天，夏天，秋天，和冬季的鲍恩比率分别地是 2.86， 0.82， 1.17，和 4.16。(2 ) 在 140-m 的高度(在经常的流动层) ，中午反照率是 0.10 夏天， 0.12 为春天和秋天，并且 0.14 为冬季。白天的比率理智的热流动，潜伏的热流动，和捕捞放射的存储热流动是 0.25， 0.16，和 0.59 清楚天空的天，并且 0.33， 0.19，和 0.48 为多云的天分别地。(3 ) 在清楚天空的天下面，夜间理智的热流动是几乎零，但是潜伏的热流动比零大。为多云的天，夜间理智的热流动比在冬季的潜伏的热流动稍微大。向上的热流动是的夜间大概由于人为的版本(为夏天的主要潜伏的热，当时为冬季的潜伏、理智的热) 。

关键词：地表能量平衡观测分析城市北京感热通量潜热通量测量分析季风气候区

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基于Conformable分数阶导数的灰色Bernoulli模型

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浙江大学学报（理学版） 2024年第2期51卷 196-204页

作者：骆世广曾亮广东金融学院金融数学与统计学院广东广州510521 广东理工学院基础课教学研究部广东肇庆526100

为增强灰色Bernoulli模型对各种实际数据序列的适应性,借助分数阶微积分在描述复杂系统中的优势,提出了一种基于Conformable分数阶导数的灰色Bernoulli模型。研究发现,可通过改变结构参数将模型转换为不同的经典灰色预测模型,体现了其... 详细信息

为增强灰色Bernoulli模型对各种实际数据序列的适应性,借助分数阶微积分在描述复杂系统中的优势,提出了一种基于Conformable分数阶导数的灰色Bernoulli模型。研究发现,可通过改变结构参数将模型转换为不同的经典灰色预测模型,体现了其统一性。此外,采用粒子群优化算法求解规划模型,获取了模型的最优超参数。最后,用所提模型和5个竞争模型对3个真实案例进行了预测建模,结果表明,所提模型的2项评估指标均优于5个竞争模型,验证了所提模型的有效性和可行性。

关键词：灰色系统 Conformable分数阶导数灰色Bernoulli模型粒子群优化算法

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Contrasting Characteristics of the Surface Energy Balance between the Urban and Rural Areas of Beijing

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Advances in Atmospheric Sciences 2015年第4期32卷 505-514页

作者： WANG Linlin GAO Zhiqiu miao shiguang GUO Xiaofeng SUN Ting Maofeng LIU Dan LI State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Institute of Urban Meteorology China Meteorological Administration State Key Laboratory of Hydroscience and Engineering Department of Hydraulic Engineering Tsinghua University Department of Civil and Environmental Engineering Princeton University Program of Atmospheric and Oceanic Sciences Princeton University

A direct comparison of urban and rural surface energy balances, as well as a variety of other variables including incoming shortwave/longwave radiation and aerosol optical depth, is conducted for the Beijing metropolitan area. The results indicate that, overall, the urban area receives a smaller amount of incoming shortwave radiation but a larger amount of incoming longwave radiation. However, comparisons in the aerosol optical depth and cloud fraction at the two locations suggest that neither aerosol optical depth nor cloud fraction alone can explain the difference in the incoming shortwave radiation. The urban–rural differences in the incoming longwave radiation are unlikely to be caused by the presence of more abundant greenhouse gases over the urban area, as suggested by some previous studies, given that water vapor is the most dominant greenhouse gas and precipitable water is found to be less in urban areas. The higher incoming longwave radiation observed over the urban area is mostly likely due to the higher temperatures of the ambient air. The urban area is also found to always produce higher sensible heat fluxes and lower latent heat fluxes in the growing season. Furthermore, the urban area is associated with a larger amount of available energy（the sum of sensible and latent heat fluxes） than the rural area, except in May and October when evapotranspiration in the rural area significantly exceeds that in the urban area. This study provides observational evidence of urban–rural contrasts in relevant energy-balance components that plausibly arise from urban–rural differences in atmospheric and land-surface conditions.

关键词： aerosol load,cloud,evapotranspiration,surface energy balance,urbanization

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