检索结果-南通市图书馆

QpefBD:A Benchmark Dataset Applied to Machine Learning for Minute-Scale Quantitative Precipitation Estimation and Forecasting

引用

Journal of meteorological Research 2022年第1期36卷 93-106页

作者： Anyuan XIONG Na LIU Yujia LIU Shulin ZHI Linlin WU Yongjian XIN Yan SHI Yunjian ZHAN National meteorological Information Center China Meteorological AdministrationBeijing 100081 Jiangxi meteorological observatory Nanchang 330096 anhui Weather Modification Office Hefei 230061

Nowcasts of strong convective precipitation and radar-based quantitative precipitation estimations have always been hot yet challenging issues in meteorological ***-driven machine learning,especially deep learning,provides a new technical approach for the quantitative estimation and forecasting of precipitation.A high-quality,large-sample,and labeled training dataset is critical for the successful application of machine-learning technology to a specific *** present study develops a benchmark dataset that can be applied to machine learning for minutescale quantitative precipitation estimation and forecasting(QpefBD),containing 231,978 samples of 3185 heavy precipitation events that occurred in 6 provinces of central and eastern China from April to October *** individual sample consists of 8 products of weather radars at 6-min intervals within the time window of the corresponding event and products of 27 physical quantities at hourly intervals that describe the atmospheric dynamic and thermodynamic *** data labels,i.e.,ground precipitation intensity and areal coverage of heavy precipitation at 6-min intervals,are also *** present study describes the basic components of the dataset and data processing and provides metrics for the evaluation of model performance on precipitation estimation and *** on these evaluation metrics,some simple and commonly used methods are applied to evaluate precipitation estimates and *** results can serve as the benchmark reference for the performance evaluation of machine learning models using this *** paper also gives some suggestions and scenarios of the QpefBD *** believe that the application of this benchmark dataset will promote interdisciplinary collaboration between meteorological sciences and artificial intelligence sciences,providing a new way for the identification and forecast of heavy precipitation.

关键词： machine learning benchmark dataset quantitative precipitation estimation precipitation forecast

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Role of Differences in Surface Diurnal–Nocturnal Thermodynamics over Complex Terrain in a Squall Line Process

引用

Journal of meteorological Research 2019年第1期33卷 1-17页

作者： Wei TAO Xuexing QIU Ruijiao WU Kun ZHOU anhui meteorological observatory China Meteorological Administration

Squall lines frequently invade the Yangtze–Huaihe River region(YHR), where the complex terrain of rivers, lakes,and mountains plays an important role in the initiation and maintenance of convection. The surface heat flux not only varies with surface conditions, but also changes between day and night. Coupled with the terrain forcing, such diurnal–nocturnal thermodynamic differences shift the low-level baroclinity, and thus further complicate the convective activities. To investigate the integrated impact of diurnal–nocturnal thermodynamic differences on the development of squall lines over complex terrain including disasters that might ensue, numerical modeling experiments on a squall line in July 2014 were performed by forcing a squall line to pass the YHR separately at daytime and nighttime. The results show that the low-level instability during the day is much larger than that during the night, and is determined predominantly by the shortwave heating of the surface. Specifically, the solar radiation enhances the temperature gradient between the warmland ahead of the squall line and the convectively generated cold pool in the region around Chaohu Lake and the Yangtze River. Such low-level baroclinity sets preconditions in the environment towards the occurrence of deep convection. The increased precipitation and the evaporation of rain in the daytime also enhance the cold pool and the associated downdraft, which further intensify the squall line. Meanwhile, the valley breeze is intensified during the day. Such scenarios promote convection that extends the squall line and the associated heavy precipitation and wind gusts southward. This research may have significant implications for enhancing the squall line prediction capability in the YHR and improving our understanding of the physical mechanisms of convective activities over complex terrain.

关键词： squall line diurnal–nocturnal thermodynamic difference(DNTD) baroclinity complex terrain

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An Extreme Gale Event in East China under the Arctic Potential Vorticity Anomaly through the Northeast China Cold Vortex

引用

Advances in Atmospheric Sciences 2023年第12期40卷 2169-2182页

作者： Wei TAO Linlin ZHENG Ying HAO Gaoping LIU anhui Meteorology observatory Hefei 230031China

Arctic changes influence not only temperature and precipitation in the midlatitudes but also contribute to severe *** study investigates an extreme gale event that occurred on 30 April 2021 in East China and was forced by an Arctic potential vorticity(PV)anomaly *** advection steered by storms contributed to the equatorward propagation of Arctic high PV,forming the Northeast China cold vortex(NCCV).At the upper levels,a PV southward intrusion guided the combination of the polar jet and the subtropical jet,providing strong vertical wind shear and downward momentum transportation to the *** PV anomaly cooled the upper troposphere and the northern part of East China,whereas the lower levels over southern East China were dominated by local warm air,thus establishing strong instability and *** addition,the entrainment of Arctic dry air strengthened the surface pressure gradient by evaporation *** the above mechanism has the potential to improve convective weather forecasts under climate *** study suggests that the more frequent NCCV-induced gale events in recent years are partly due to high-latitude waviness and storm activities,and this hypothesis needs to be investigated using more cases.

关键词： PV anomaly Arctic storm Northeast China cold vortex convection extreme gale

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Influence of self-similar stresses on scenario earthquake construction:An example along the Tanlu Fault

引用

Science China Earth Sciences 2024年第5期67卷 1687-1697页

作者： Feng HU Huajian YAO Houyun YU Zeyu LU Jieyi HOU Song LUO Zhigang SHAO Xiaofei CHEN School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Mengcheng Geophysical National Field Scientific observatory Hefei 230026China Department of Earth and Space Science Southern University of Science and TechnologyShenzhen 518055China Institute of Earthquake Prediction China Earthquake AdministrationBeijing 100036China

As a famous deep and large fault in eastern China,the Tanlu Fault passes through anhui,Jiangsu,and Shandong and into northeastern *** is important to improve the understanding of seismic hazard assessments in areas near *** start a scenario earthquake simulation in the M7.5 earthquake potential area of the Xinyi-Sihong segment of the Tanlu *** fault rupture length and width are constrained according to the scaling law of large intraplate earthquakes,the background normal stress is depth dependent,and the initial shear stresses are determined using trial and error by matching the earthquake *** the 120 km rupture length of the M7.5 earthquake,we compare the horizontal uniform stress model and self-similar stress perturbation *** findings reveal that the seismic source time function of the horizontal uniform stress model is similar to that of the Haskell model and that of the self-similar stress perturbation model is more similar to that of a real earthquake *** compare the dynamic rupture simulation and ground motion results under four different stress conditions and find that the shorter the characteristic length of the self-similar function is,the rougher the initial *** the M7.5earthquake with an epicenter in the vicinity of Suqian,the Xinyi-Tancheng segment,which is located in the IX-intensity zone north of the epicenter,vibrates more strongly on the northern side than on the southern side due to the influence of the lowvelocity zone and the peak slip *** response spectra analysis at stations in the study area is useful for improving the earthquake resistance capability.

关键词： Scenario earthquakes Self-similar stress Tanlu Fault Dynamic rupture Ground motion

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Measurement of HONO flux using the aerodynamic gradient method over an agricultural field in the Huaihe River Basin,China

引用

Journal of Environmental Sciences 2022年第4期34卷 297-307页

作者： Fanhao Meng Min Qin Wu Fang Jun Duan Ke Tang Helu Zhang Dou Shao Zhitang Liao Yan Feng Yong Huang Ting Ni Pinhua Xie Jianguo Liu Wenqing Liu Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China anhui Institute of meteorological Sciences Anhui Province Key Laboratory of Atmospheric Science and Satellite Remote SensingHefei 230031China Shouxian National Climatology observatory Huaihe River Basin Typical Farm Eco-meteorological Experiment Field of China Meteorological AdministrationShouxian 232200China

To investigate nitrous acid(HONO)levels and potential HONO sources above crop rotation *** HONO fluxes were measured by the aerodynamic gradient(AG)method from 14 December 2019 to 2 January 2020 over an agricultural field in the Huaihe River *** ambient HONO levels were measured at two different heights(0.15 and 1.5 m),showing a typical diurnal cycle with low daytime levels and high nighttime *** upward HONO fluxes were mostly observed during the day,whereas deposition dominated at *** diurnal variation of HONO flux followed solar radiation,with a noontime maximum of 0.2 nmol/(m^(2)·sec).The average upward HONO flux of 0.06±0.17 nmol/(m^(2)·sec)indicated that the agricultural field was a net source for atmospheric *** higher HONO/NO_(2)ratio and NO_(2)-to-HONO conversion rate close to the surface suggested that nocturnal HONO was formed and released near the *** unknown HONO source was derived from the daytime HONO budget analysis,with an average strength of 0.31 ppbV/hr at *** surface HONO flux,which was highly correlated with the photolysis frequency J(NO_(2))(R^(2)=0.925)and the product of J(NO_(2))×NO_(2)(R^(2)=0.840),accounted for∼23%of unknown daytime HONO *** significant correlation between HONO fluxes and J(NO_(2))suggests a light-driven HONO formation mechanism responsible for the surface HONO flux during daytime.

关键词： Aerodynamic gradient method HONO flux Huaihe River Basin Agricultural field

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Climate Analysis of Tornadoes in China

引用

Journal of meteorological Research 2015年第3期29卷 359-369页

作者：姚叶青俞小鼎张义军周自江谢五三卢燕宇余金龙魏凌翔 Nanjing University of Information Science & Technology Chinese Academy of meteorological Sciences anhui meteorological observatory China meteorological Administration Training Center National meteorological Information Center China Meteorological Administration anhui Province Climate Center

Based on analysis of historical tornado observation data provided by the primary network of national weather stations in China for the period from 1960 to 2009, it is found that most tornadoes in China （85%） occurred over plains. Specifically, large numbers of tornado occurrences are found in the Northeast Plain, the North China Plain, the middle-lower Yangtze Plain, and the Pearl River Delta Plain. A flat underlying surface is conducive to tornado occurrence, while the latitudal variation of tornado occurrence in China is not so obvious. Tornadoes mainly occur in summer, and the highest frequency is in July. Note that the beginning and the time span of tornado outbreaks are different in North and South China. Tornadoes occur during May-September in South China （south of 25°N）, June-September in Northeast China （north of 40°N）, July-September in the middle-lower Yangtze Plain, and July-August in North China （between 25° and 40°N）. More than 80% of total tornadoes occurred during the above periods for the specific regions. The 1960s and 1970s have seen about twice the average number of tornadoes （7.5 times per year） compared to the mean for 1960-2009. The most frequent occurrence of tornado was in the early and mid 1960s; there were large fluctuations in the 1970s; and the number of tornadoes in the 1980s approached the 50-yr average. Tornado occurrences gradually decreased in the late 1980s, and an abrupt change with dramatic decrease occurred in 1994. The decrease in the tornado occurrence frequency is consistent with the simultaneous climatic change in the meteorological elements that are favorable for tornado formation. Tornado formation requires large vertical wind shear and sufficient atmospheric moisture content near the ground. Changes in the vertical wind shear at both 0-1 and 0-6 km appear to be one important factor that results in the decrease in tornado formation. The changing tendency of relative humidity also has contributed to the decrease in tornado

关键词： tornado China climate change

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The Evolution of a Meso-β-Scale Convective Vortex in the Dabie Mountain Area

引用

Acta meteorologica Sinica 2012年第5期26卷 597-613页

作者：徐文慧倪允琪汪小康邱学兴 National meteorological Information Center Chinese Academy of meteorological Sciences Wuhan Institute of Heavy Rain anhui meteorological observatory

The evolution of a mesoscale convective system （MCS） that caused strong precipitation in the northern area of Dabie Mountain during 21 22 June 2008 is analyzed, along with the evolution of the associated meso-β-scale convective vortex （MCV）. The mesoscale reanalysis data generated by the Local Analysis and Prediction System （LAPS） at a 3-km horizontal resolution and a 1-h time resolution during the South China Heavy Rainfall Experiment （SCHeREX） were utilized. The results show that two processes played key roles in the enhancement of convective instability. First, the mesoscale low-level jet strengthened and shifted eastward, leading to the convergence of warm-wet airflow and increasing convective instability at middle and low levels. Second, the warm-wet airflow interacted with the cold airflow from the north, causing increased vertical vorticity in the vicinity of steeply sloping moist isentropic surfaces. The combined action of these two processes caused the MCS to shift progressively eastward. Condensation associated with the MCS released latent heat and formed a layer of large diabatic heating in the middle troposphere, increasing the potential vorticity below this layer. This increase in potential vorticity created favorable conditions for the development of a low-level vortex circulation. The vertical motion associated with this low-level vortex further promoted the development of convection, creating a positive feedback between the deep convection and the low-level vortex circulation. This feedback mechanism not only promoted the maturation of the MCS, but also played the primary role in the evolution of the MCV. The MCV formed and developed due to the enhancement of the positive feedback that accompanied the coming together of the center of the vortex and the center of the convection. The positive feedback peaked and the MCV matured when these two centers converged. The positive feedback weakened and the MCV began to decay as the two centers separated and d

关键词： mesoscale reanalysis data mesoscale convective vortex mesoscale convective system evolu-tional mechanism positive feedback

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The Statistical Significance Test of Regional Climate Change Caused by Land Use and Land Cover Variation in West China

引用

Advances in Atmospheric Sciences 2006年第3期23卷 355-364页

作者：王汉杰施伟来陈晓红 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Meteorology anhui meteorological observatory

The West Development Policy being implemented in China is causing significant land use and land cover （LULC） changes in West China. With the up-to-date satellite database of the Global Land Cover Characteristics Database （GLCCD） that characterizes the lower boundary conditions, the regional climate model RIEMS-TEA is used to simulate possible impacts of the significant LULC variation. The model was run for five continuous three-month periods from 1 June to 1 September of 1993, 1994, 1995, 1996, and 1997, and the results of the five groups are examined by means of a student t-test to identify the statistical significance of regional climate variation. The main results are：（1） The regional climate is affected by the LULC variation because the equilibrium of water and heat transfer in the air-vegetation interface is changed. （2） The integrated impact of the LULC variation on regional climate is not only limited to West China where the LULC varies, but also to some areas in the model domain where the LULC does not vary at all. （3） The East Asian monsoon system and its vertical structure are adjusted by the large scale LULC variation in western China, where the consequences are the enhancement of the westward water vapor transfer from the east oast and the relevant increase of wet-hydrostatic energy in the middle-upper atmospheric layers. （4） The ecological engineering in West China affects significantly the regional climate in Northwest China, North China and the middle-lower reaches of the Yangtze River; there are obvious effects in South, Northeast, and Southwest China, but minor effects in Tibet.

关键词： West Development Policy of China LULC variation regional climate simulation statistical t-test East Asian monsoon

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Study of Structure and Mechanism of a Meso-beta-scale Convective Vortex and Associated Heavy Rainfall in the Dabie Mountain Area Part I: Diagnostic Analysis of the Structure

引用

Advances in Atmospheric Sciences 2011年第5期28卷 1159-1176页

作者：徐文慧倪允琪汪小康邱学兴宝兴华金文岩 School of Atmospheric Science Nanjing University Nanjing 210093 National meteorological Information Center Beijing 100081 State Key Lab of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 anhui meteorological observatory Hefei 230031 Pu Landian meteorological observatory Pu Landian 116200

An analysis was conducted on the evolutional process of a mesoscale convective vortex （MCV） and associated heavy rainfall in the Dabie Mountain area on 21-22 June 2008,as well as their structural characteristics in different stages,by using the mesoscale reanalysis data with 3 km and 1 h resolution generated by the Local Analysis and Prediction System （LAPS） in the Southern China Heavy Rainfall *** results showed that the latent heat released by convection in the midtroposphere was the main energy source for the development of a low-level *** was a positive feedback interaction between the convection and the vortex,and the evolution of the MCV was closely related to the strength of the positive *** most typical characteristics of the thermal structure in different stages were that,there was a relatively thin diabatic heating layer in the midtroposphere in the formative stage;the thickness of diabatic heating layer significantly increased in the mature stage;and it almost disappeared in the decay *** characteristics of the dynamic structure were that,in the formative stage,there was no anticyclonic circulation at the high level;in the mature stage,an anticyclonic circulation with strong divergence was formed at the high level;in the decay stage,the anticyclonic circulation was damaged and the high-level atmosphere was in a disordered state of ***,the structural schematics of the MCV in the formative and mature stage were established respectively.

关键词： mesoscale reanalysis data mesoscale convective vortex (MCV) strong convection positive feedback structural schematics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Water Cycle and Microphysical Processes Associated with a Mesoscale Convective Vortex System in the Dabie Mountain Area

引用

Advances in Atmospheric Sciences 2011年第6期28卷 1405-1422页

作者：汪小康倪允琪徐文慧顾春利邱学兴 School of Atmospheric Sciences Nanjing University Institute of Heavy Rain China Meteorological Administration State Key Lab of Severe Weather Chinese Academy of Meteorological Sciences Beijing Institute of Applied Meteorology anhui meteorological observatory

The water vapor budget and the cloud microphysical processes associated with a heavy rainfall system in the Dabie Mountain area in June 2008 were analyzed using mesoscale reanalysis data（grid resolution 0.03 × 0.03,22 vertical layers,1-h intervals）,generated by amalgamating the local analysis and prediction system（LAPS）.The contribution of each term in the water vapor budget formula to precipitation was *** characteristics of water vapor budget and water substances in various phase states were evaluated and their differences in heavy and weak rainfall areas were *** precipitation calculated from the total water vapor budget accounted for 77% of actual precipitation;surface evaporation is another important source of water *** vapor within the domain of interest mainly came from the lower level along the southern boundary and the lower-middle level along the western *** altitude difference for water vapor flux was caused by different weather *** decrease of local water vapor in the middle-lower layer in the troposphere during the system development stage also contributed to *** strength and the layer thickness of water vapor convergence and the content of various water substances in the heavy rainfall areas were obviously larger than in the weak rainfall *** peak values of lower-level water vapor convergence,local water vapor income,and the concentration of cloud ice all preceded the heaviest surface rainfall by a few hours.

关键词： water vapor budget water substance SCHeREX data heavy rainfall

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：