检索结果-南通市图书馆

SEASONAL CIRCULATION IN THE NORTHWESTERN TROPICAL PACIFIC OCEAN DIAGNOSED WITH THE ASSIMILATION DATA FROM 1989 THROUGH 1997

引用

Journal of Hydrodynamics 2001年第3期13卷 65-73页

作者： Wang, Fan Chang, Ping Hu, Dun-Xin Howard, Seidel Inst. of Oceanology Chinese Acad. of Sci. Qingdao 266071 China

An assimilation data set based on the Geophysical Fluid Dynamics Laboratory (GFDL) Modular Ocean Model version 3 (MOM3) and the NODC XBT data set is used to examine the circulation and its variabilities in the western tropical Pacific, with special emphasis on the seasonal variations. It is shown that the assimilated and observed mean velocities and transports of the major flows in the western tropical Pacific agree well. The flows in the north Pacific, including the North Equatorial Current (NEC), Kuroshio, Mindanao Current (MC) and north Equatorial Countercurrent (NECC) west of 140°E display the seasonal cycles almost in the same phase, with the biggest transport in spring and the smallest in autumn. The phase of the NECC seasonal cycle east of 140°E is opposite to that in the west. Besides of the annual cycle, there seems to be a semi-annual fluctuation of the NECC transport possibly resulting from the phase lag between seasonal cycles of the NEC and NGCC. Strong in summer during the southeast monsoon, the seasonal cycle of the Indonesian Throughflow (ITF) is closely linked with those of both the MC and the New Guinea Coastal Current/Undercurrent (NGCC/NGCUC), but not as strong as that in observations probably caused by the superimposed seasonal and interannual variations. Variations on the interannual time scale are also discussed, but only indistinct interannual variations of the flows related to the ENSO are revealed during 1989-1997. Transport of the NEC, Kuroshio and NECC are slightly larger in the E1 Nino years when that of the ITF is weaker, while the MC has little ENSO-related variation. There were also quasi-biennial signals superimposing the ENSO-like oscillations in the flows, but their relationships with the ENSO are still unclear.

关键词： climatology Data handling Flow of water

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 28-Year Climatological Analysis of Size Parameters for Northwestern Pacific Tropical Cyclones

引用

Advances in Atmospheric Sciences 2007年第1期24卷 24-34页

作者：袁金南王东晓万齐林刘春霞 Guangzhou Institute of Tropical and Marine Meteorology China Meteorological AdministrationGuangzhou 510080 Laboratory for Tropical Marine Environmental Dynamics South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301

A 28-year best track dataset containing size parameters that include the radii of the 15.4 m s^-1 winds （R15） and the 25.7 m s^-1 winds （R26） of tropical cyclones （TCs） in the Northwestern Pacific, the NCEP/ NCAR reanalysis dataset and the Extended Reconstructed Sea Surface Temperature （ERSST） dataset are employed in this study. The climatology of size parameters for the tropical cyclones in the Northwestern Pacific from 1977 to 2004 is investigated in terms of the spatial and temporal distributions. The results show that the major activity of TCs in the Northwestern Pacific is from July to October. A majority of TCs lie over the ocean west of 150°E, and a few TCs can intensify to the Saffir-Simpson （S-S） categories 4, 5. Both R15 and R26 tend to increase as the tropical cyclones intensify. The values of R15 and R26 are larger for intense TCs in the Northwestern Pacific than in the North Atlantic generally. Both R15 and R26 peak in October, and before and after October, R15 and R26 decrease, which is different from the case in the North Atlantic. The smaller R15s and R26s occur in a large range over the Northwestern Pacific, while the larger R15s and R26s mainly lie in the eastern ocean from Taiwan Island to the Philippine Islands where many tropical cyclones develop in intense systems. The tropical cyclones with size parameters of R15 or R26 on average take a longer time to intensify than to weaken, and the weak tropical cyclones have faster weakening rates than intensification rates. From 1977 to 2004, the annual mean values of R15 increase basically with year; during the 28-year period, the value of R15 increases by 52.7 kin, but R26 does not change with year obviously.

关键词： climatology size parameters of tropical cyclones Northwestern Pacific a 28-year best track dataset

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

Evaluation of CMIP5 Climate Models in Simulating 1979–2005 Oceanic Latent Heat Flux over the Pacific

引用

Advances in Atmospheric Sciences 2015年第12期32卷 1603-1616页

作者： CAO Ning REN Baohua ZHENG Jianqiu School of Earth and Space Sciences University of Science and Technology of China Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology

The climatological mean state, seasonal variation and long-term upward trend of 1979-2005 latent heat flux （LHF） in historical runs of 14 coupled general circulation models from CMIP5 （Coupled Model Intercomparison Project Phase 5） are evaluated against OAFlux （Objectively Analyzed air-sea Fluxes） data. Inter-model diversity of these models in simulating the annual mean climatological LHF is discussed. Results show that the models can capture the climatological LHF fairly well, but the amplitudes are generally overestimated. Model-simulated seasonal variations of LHF match well with observations with overestimated amplitudes. The possible origins of these biases are wind speed biases in the CMIP5 models. Inter-model diversity analysis shows that the overall stronger or weaker LHF over the tropical and subtropical Pacific region, and the meridional variability of LHF, are the two most notable diversities of the CMIP5 models. Regression analysis indicates that the inter-model diversity may come from the diversity of simulated SST and near-surface atmospheric specific humidity. Comparing the observed long-term upward trend, the trends of LHF and wind speed are largely underestimated, while trends of SST and air specific humidity are grossly overestimated, which may be the origins of the model biases in reproducing the trend of LHF.

关键词： model evaluation climatology trend latent heat flux CMIP5

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 Significant Role of Radiosonde-measured Cloud-base Height in the Estimation of Cloud Radiative Forcing

引用

Advances in Atmospheric Sciences 2021年第9期38卷 1552-1565页

作者： Hui XU Jianping GUO Jian LI Lin LIU Tianmeng CHEN Xiaoran GUO Yanmin LYU Ding WANG Yi HAN Qi CHEN Yong ZHANG State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China College of Earth Sciences University of Chinese Academy of SciencesBeijing 100049China Meteorological Observation Center China Meteorological AdministrationBeijing 100081China

The satellite-based quantification of cloud radiative forcing remains poorly understood,due largely to the limitation or uncertainties in characterizing cloud-base height(CBH).Here,we use the CBH data from radiosonde measurements over China in combination with the collocated cloud-top height(CTH) and cloud properties from MODIS/Aqua to quantify the impact of CBH on shortwave cloud radiative forcing(SWCRF).The climatological mean SWCRF at the surface(SWCRFSUR),at the top of the atmosphere(SWCRFTOA),and in the atmosphere(SWCRFATM) are estimated to be-97.14,-84.35,and 12.79 W m^(-2),respectively for the summers spanning 2010 to 2018 over China.To illustrate the role of the cloud base,we assume four scenarios according to vertical profile patterns of cloud optical depth(COD).Using the CTH and cloud properties from MODIS alone results in large uncertainties for the estimation of SWCRFATM,compared with those under scenarios that consider the CBH.Furthermore,the biases of the CERES estimation of SWCRFATM tend to increase in the presence of thick clouds with low CBH.Additionally,the discrepancy of SWCRFATM relative to that calculated without consideration of CBH varies according to the vertical profile of COD.When a uniform COD vertical profile is assumed,the largest SWCRF discrepancies occur during the early morning or late afternoon.By comparison,the two-point COD vertical distribution assumption has the largest uncertainties occurring at noon when the solar irradiation peaks.These findings justify the urgent need to consider the cloud vertical structures when calculating the SWCRF which is otherwise neglected.

关键词： cloud base height radiosonde radiative forcing China climatology

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

Characterization of Drought and Its Assessment over Sindh,Pakistan During 1951-2010

引用

Journal of Meteorological Research 2015年第5期29卷 837-857页

作者： Shahzada ADNAN Kalim ULLAH 高守亭 Department of Meteorology COMSATS Institute of Information Technology(CIIT) National Drought Monitoring Centre Pakistan Meteorological Department Institute of Atmospheric Physics Chinese Academy of Sciences State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences

Drought is one of the complex meteorological disasters affecting water resources, agriculture, livestock, and socioeconomic patterns of a region. Although drought prediction is difficult, it can be monitored based on climatological information. In this study, we provide high spatiotemporal resolution drought climatology, using observational, gridded precipitation data （0.5°×0.5°） from the Global Precipitation Climatological Center and soil moisture data from the Climate Prediction Center for the 60-yr period 1951-2010. The standardized precipitation index （SPI） based on a fitted Gamma distribution and Run method has been calculated from the regional drought identification model （ReDIM） for 3, 6, 9, 12, and 24 months. The results show strong temporal correlations among anomalies of precipitation, soil moisture, and SPI. Analysis of long-term precipitation data reveals that the drought vulnerability concentrates on monsoon season （July- September）, which contributes 72.4% and 82.1% of the annual precipitation in northern and southern Sindh, respectively. Annual and seasonal analyses show no significant changes in the observed precipitation. The category classification criteria are defined to monitor/forecast drought in the selected area. Further analysis identifies two longest episodes of drought, i.e., 1972 1974 and 2000 2002, while 1969, 1974, 1987, and 2002 are found to be the most severe historical drought years. A drought hazard map of Sindh was developed, in which 10 districts are recognized as highly vulnerable to drought. This study helps to explain the time, duration, intensity, and frequency of meteorological droughts over Sindh as well as its neighboring regions, and provides useful information to disaster management agencies and forecasters for assessing both the regional vulnerabilitv of drought and its seasonal predictability in Pakistan.

关键词： climatology drought standardized precipitation index （SPI） regional drought identification model （ReDIM） Sindh

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

Differences between CMIP6 and CMIP5 Models in Simulating Climate over China and the East Asian Monsoon

引用

Advances in Atmospheric Sciences 2020年第10期37卷 1102-1118,I0002-I0017页

作者： Dabang JIANG Dan HU Zhiping TIAN and Xianmei LANG Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China

We compare the ability of coupled global climate models from the phases 5 and 6 of the Coupled Model Intercomparison Project(CMIP5 and CMIP6,respectively)in simulating the temperature and precipitation climatology and interannual variability over China for the period 1961–2005 and the climatological East Asian monsoon for the period 1979–2005.All 92 models are able to simulate the geographical distribution of the above variables reasonably well.Compared with earlier CMIP5 models,current CMIP6 models have nationally weaker cold biases,a similar nationwide overestimation of precipitation and a weaker underestimation of the southeast–northwest precipitation gradient,a comparable overestimation of the spatial variability of the interannual variability,and a similar underestimation of the strength of winter monsoon over northern Asia.Pairwise comparison indicates that models have improved from CMIP5 to CMIP6 for climatological temperature and precipitation and winter monsoon but display little improvement for the interannual temperature and precipitation variability and summer monsoon.The ability of models relates to their horizontal resolutions in certain aspects.Both the multi-model arithmetic mean and median display similar skills and outperform most of the individual models in all considered aspects.

关键词： global climate models climatology interannual variability model performance China East Asia

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

Towards a Link between Climate Extremes and Thermodynamic Patterns in the City of Rio de Janeiro-Brazil: Climatological Aspects and Identified Changes

引用

Journal of Geoscience and Environment Protection 2023年第8期11卷 131-160页

作者： Wanderson Luiz-Silva Fabricio Polifke da Silva Claudine Pereira Dereczynski José Ricardo de Almeida França Department of Meteorology Institute of Geosciences Federal University of Rio de Janeiro Rio de Janeiro Brazil

Modification signs in extreme weather events may be directly related to alterations in the thermodynamic panorama of the atmosphere that need to be better understood. This study aimed to make a first interconnection between climate extremes and thermodynamic patterns in the city of Rio de Janeiro. Maximum and minimum air temperature and precipitation extreme indices from two surface meteorological stations (ABOV and STCZ) and instability indices based on temperature and humidity from radiosonde observations (SBGL) were employed to investigate changes in the periods 1964-1980 (P1), 1981-2000 (P2), and 2001-2020 (P3). Statistical tests were adopted to determine the significance and magnitude of trends. The frequency of warm (cold) days and warm (cold) nights are increasing (decreasing) in the city. Cold (Warm) extremes are changing with greater magnitude in ABOV (STCZ) than in STCZ (ABOV). In ABOV, there is a significant increase of +84 mm/decade in the rainfall volume associated with severe precipitation (above the 95th percentile) and most extreme precipitation indices show an increase in frequency and intensity. In STCZ, there is a decrease in extreme precipitation until the 1990s, and from there, an increase, showing a wetter climate in the most recent years. It is also verified in SBGL that there is a statistically significant increase (decrease) in air temperature of +0.1°C/decade (-0.2°C/decade) and relative humidity of +1.2%/decade (-3%/decade) at the low and middle (high) troposphere. There is a visible rising trend in most of the evaluated instability indices over the last few decades. The increasing trends of some extreme precipitation indices are probably allied to the precipitable water increasing trend of +1.2 mm/decade.

关键词： Climate Change climatology Instability Indices Precipitation Extremes Temperature Extremes

来源：

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

Statistical Analysis of Precipitation Extremes in São Francisco River Basin, Brazil

引用

Atmospheric and Climate Sciences 2022年第2期12卷 383-408页

作者： Nayara Arroxelas dos Santos Siqueira Anderlan Henrique Batista Siqueira Augusto José Pereira Filho Departamento de Ciências Atmosféricas Instituto de Astronomia Geofísica e Ciências Atmosféricas Universidade de S&#227 o Paulo S&#227 o Paulo Brazil Instituto de Ciências Atmosféricas Universidade Federal de Alagoas Alagoas Brazil

This study comprises a climatology of the spatial variability of precipitation over the São Francisco River Basin (SFRB), characterized by its geographic heterogeneity. The different rainfall regimes in the region were analyzed through statistical and spectral analyses. Measured precipitation data, Pacific Decennial Climate indexes, ENSO, Atlantic Multidecadal Oscillation, North Atlantic Oscillation, Atlantic dipole, and the sunspot cycle over 65 years were used. The rainfall data were filtered and filled in using the regional weighting method. The spatial and temporal variability of precipitation along the SFRB is remarkable. A pattern was observed along with the time series of precipitation over the SFRB. The cluster analysis identified four homogeneous regions in the SFRB and explained 87.4% of the total variance of the average monthly rainfall of the 199 rain gauges. The Cross-wavelet analysis identified the relationship between the precipitation data series and the climatic indexes that are analyzed in this work.

关键词： Cross-Wavelet Statistical Analysis Hydrometeorology climatology

来源：

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

SIMULATION OF TROPICAL CYCLONES OVER THE WESTERN NORTH PACIFIC AND LANDFALLING IN CHINA BY REGCM4

引用

Journal of Tropical Meteorology 2019年第4期25卷 437-447页

作者：吴婕高学杰 Climate Change Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044 China

This study evaluates the performance of the regional climate model RegCM4 in simulating tropical cyclone(TC) activities over the Western North Pacific(WNP) and their landfalling in China. The model is driven by ERA-Interim boundary conditions at a grid spacing of 25 km, with the simulation period as 1991-2010. Results show that RegCM4 performs well in capturing the main structural features of observed TCs, and in simulating the genesis number and annual cycle of the genesis. The model reproduces the general pattern of the observed TC tracks and occurrence frequency. However, significant underestimation of the occurrence frequency as well as the TC intensity is found. Number of the landfalling TCs over China is also much smaller than that of the observed. Bias of the model in reproducing the large-scale circulation pattern and steering flow may contribute to the underestimated landfalling TC numbers.

关键词： climatology tropical cyclone RegCM western North Pacific landfall

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

RELATIONSHIP BETWEEN THE 30 TO 60 DAY OSCILLATION OF ATMOSPHERIC HEAT SOURCE AND THE DROUGHT AND FLOOD EVENTS IN JUNE IN THE SOUTH OF CHINA

引用

Journal of Tropical Meteorology 2012年第3期18卷 332-340页

作者：高斯简茂球乔云亭 Centre for Monsoon and Environment Research Department of Atmospheric SciencesSchool of Environmental Science and EngineeringSun Yat-sen University

Based on the NCEP/NCAR reanalysis data and the observed precipitation data in the south of China from 1958 to 2000,the impact of 30 to 60 day oscillation of atmospheric heat sources on the drought and flood events in June in the south of China is discussed.During the flood(drought) events,there exists an anomalous low-frequency anticyclone(cyclone) at the low level of the troposphere over the South China Sea and the northwestern Pacific,accompanied with anomalous low-frequency heat sinks(heat sources),while there exists an anomalous low-frequency cyclone(anticyclone) with anomalous heat sources(sinks) over the area from the south of China to the south of Japan.On average,the phase evolution of the low-frequency in drought events is 7 to 11 days ahead of that in flood events in May to June in the south of China.In flood events,low-frequency heat sources and cyclones are propagated northward from the southern South China Sea,northwestward from the warm pool of the western Pacific and westward from the northwestern Pacific around 140°E,which have very important impact on the abundant rainfall in June in the south of China.However,in drought events,the northward propagations of the low-frequency heat sources and cyclones from the South China Sea and its vicinity are rather late compared with those in flood events,and there is no obvious westward propagation of the heat sources from the northwestern Pacific.The timing of the low-frequency heat source propagation has remarkable impact on the June rainfall in the south of China.

关键词： climatology statistical feature atmospheric heat source 30-60 day oscillation flood and drought the south of China

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：