检索结果-南通市图书馆

Semi-analytical analysis of the response of the air temperature over the land surface to the global vegetation distribution

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2009年第14期54卷 2499-2505页

作者： LIU fei1,2.& {2. JiPing3,4 1 Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., China 2.Graduate University of Chinese Academy of Sciences, beijing 100049, China 3 national Marine environmental forecasting center, beijing 1.0081. China 4 First Institute of Oceanography, State Oceanic Administration of China, Qingdao 2.6061, China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China national Marine {1. {2. center Beijing 100081 China First Institute of Oceanography State Oceanic Administration of China Qingdao 266061 China

Response of the air temperature over the land surface to the global vegetation distribution is investigated, using a three-dimensional governing equation to simulate the steady, large-scale, limited amplitude perturbation of the free, inviscid and adiabatic atmosphere. The adoption of the static equation leads to a temperature governing equation in the terrain following coordinate. With the prescribed temperature as the upper boundary condition and the radiation balance as the lower boundary condition, the semi-analytical solution of the global circulation temperature can be calculated. In this article, only the air temperature (at 2.m height) over the land surface is analyzed, and the result suggests that this model can simulate the air temperature pattern over the land surface reasonably. A better simulation occurs when a simple feedback of the albedo on the temperature is included. Two sensitivity experiments are analyzed through this model. One suggests that the air temperature over the land surface descends obviously when the land surface is covered with ice all over, while another suggests that the air temperature rises a little when the land surface is covered with forest except the ice-covered area. This model appears to be a good tool to study the response of the air temperature to the vegetation distribution. Limitations of the model are also discussed.

关键词：空气温度植被分布陆地表面反应解析分析模拟模式控制方程边界条件

The coupling instability of Rossby and topographic Rossby waves in the equatorial area

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2005年第10期48卷 1792-1801页

作者： chao Jiping1.2. LIU Lin1.3 & YU Weidong1.1. Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 2.6061. China 2. {1. Research center for Marine environmental Forecasts, State Oceanic Administration, beijing 1.0081. China 3. Ocean University of China, Qingdao 2.6003, China Laboratory of Marine Science and Numerical Modeling State Oceanic Administration Qingdao China national Research {1. for Marine {2. Forecasts State Oceanic Administration beijing China Ocean University of China Qingdao China

In case of considering the fact that the tropical ocean thermocline or the lower at-mosphere height field has the meridional variation, the topographic Rossby wave will be excited. Also the background geostrophic current emerges. Under such conditions, the topographic Rossby wave can interact with the classical Rossby wave at some parameter band and thus brings a new kind of instability, which may be of potential application in understanding some phenomena of the ENSO cycle.

关键词： thermocline variation, equatorial jet, Rossby wave, topographic Rossby wave, coupling instability

Evolution of desertification in a two-dimensional energy balance model coupled with thermodynamics and dynamics

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2010年第11期53卷 1726-1733页

作者： chao JiPing1.{1. LI YaoKun3,4 1.2. Marine environmental forecasting center, beijing 1.0081. China 2.irst Institute of Oceanography, State Oceanic Administration, Qingdao 2.6061. China 3State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 1.002., China 4Graduate University of Chinese Academy of Sciences, beijing 1.0049, China 1. national Marine {1. forecasting center Beijing 100081 China2. First Institute of Oceanography State Oceanic Administration Qingdao 266061 China3. State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China4. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The relationship between desert evolution and change in albedo has been investigated quasi-analytically using a zonal mean two-dimensional energy balance model which considers the radiation transmission process due to thermodynamics and bound- ary layer movement caused by kinetics. A climate state including temperature, zonal wind, meridional wind and vertical wind can be simulated according to the current zonal distribution of albedo. Given desert distribution, characterized by the value and distribution of albedo, the response of climate on albedo has been studied to analyze the evolution of desert climate. One significant result is that the simple model can reproduce mean meridional circulation. Another result indicates that climate corresponds to two equilibria. This happens when the junction temperature between vegetation and desert is higher than a certain critical value. As for the first equilibrium, the desert belt is predicted to move southward in the northern hemisphere with the increasing values of albedo, which corresponds to the current trend of climate change. For the second equilibrium, vegetation will expand northward with increasing values of albedo, which would indicate a narrowing of the desert belt. In order to determine if the two equilibria exist, new physical models are needed.

关键词： two-dimensional energy balance model desertification two equilibria

Heat exposure and hospitalizations for chronic kidney disease in China: a nationwide time series study in 2.1.major Chinese cities

在线全文

学校读者我要写书评

暂无评论

Military Medical Research 2024年第4期11卷 469-478页

作者： Fu-Lin Wang Wan-Zhou Wang fei-fei Zhang Su-Yuan Peng Huai-Yu Wang Rui Chen Jin-Wei Wang Peng-fei Li Yang Wang Ming-Hui Zhao chao Yang Lu-Xia Zhang Institute of Medical Technology Peking University Health Science CenterBeijing 100191China national Institute of Health Data Science at Peking University Beijing 100191China Department of Occupational and environmental Health Sciences School of Public HealthPeking UniversityBeijing 100191China Renal Division Department of MedicinePeking University First HospitalPeking University Institute of NephrologyBeijing 100034China Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases Chinese Academy of Medical SciencesBeijing 100034China Advanced Institute of Information Technology Peking UniversityHangzhou 311215China national Climate {1. China Meteorological AdministrationBeijing 100081China Peking-Tsinghua center for Life Sciences Beijing 100034China

Background:Climate change profoundly shapes the population health at the global ***,there was still insufficient and inconsistent evidence for the association between heat exposure and chronic kidney disease(CKD).Methods:In the present study,we studied the association of heat exposure with hospitalizations for cause-specific CKD using a national inpatient database in China during the study period of hot season from 2.1. to *** time-series regression models and random-effects Meta-analysis were developed to estimate the city-specific and national averaged associations at a 7 lag-day span,***:A total of 768,12. hospitalizations for CKD was recorded during the study *** results showed that higher temperature was associated with elevated risk of hospitalizations for CKD,especially in sub-tropical *** a 1. increase in daily mean temperature,the cumulative relative risks(RR)over lag 0-7 d were 1.008[95% confidence interval(CI)1.003-1.012.for *** attributable fraction of CKD hospitalizations due to high temperatures was 5.50%.Stronger associations were observed among younger patients and those with obstructive *** study also found that exposure to heatwaves was associated with added risk of hospitalizations for CKD compared to non-heatwave days(RR=1.1.6,95%CI 1.069-1.1.6)above the effect of daily mean ***:Short-term heat exposure may increase the risk of hospitalization for *** findings provide insights into the health effects of climate change and suggest the necessity of guided protection strategies against the adverse effects of high temperatures.

关键词： Chronic kidney disease Hospitalization Climate change Temperature Time-series study

Distinguished Effects of Interannual Salinity Variability on the Development of the Central-Pacific El Ni o Events

在线全文

学校读者我要写书评

暂无评论

Atmospheric and Oceanic Science Letters 2012年第2期5卷 123-127页

作者： ZHENG fei 1,WAN Li-Ying 2.and WANG Hui 3 1 International {2. for Climate and Environment Science (ICCES),Institute of Atmospheric Physics,Chinese Academy of Sciences,beijing 10002.,China 2.Key Laboratory of Research on Marine Hazards forecasting,national Marine environmental forecasting {2.,beijing 1.0081.China 3 national Meteorological {2.,beijing 1.0081.China [a] International {1. for Climate and Environment Science (ICCES) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China[b] Key Laboratory of Research on Marine Hazards Forecasting National Marine Environmental Forecasting Center Beijing 100081 China[c] National Meteorological Center Beijing 100081 China

El Nio events in the central equatorial Pacific (CP) are gaining increased attention,due to their increasing intensity within the global warming *** physical processes have been identified in the climate system that can be responsible for the modulation of El Nio,especially the effects of interannual salinity *** this work,a comprehensive data analysis is performed to illustrate the effects of interannual salinity variability using surface and subsurface salinity fields from the Met Office ENSEMBLES (EN3) quality controlled ocean *** is demonstrated that during the developing phase of an El Nio event,a negative sea surface salinity (SSS) anomaly in the western-central basin acts to freshen the mixed layer (ML),decrease oceanic density in the upper ocean,and stabilize the upper *** related oceanic processes tend to reduce the vertical mixing and entrainment of subsurface water at the base of the ML,which further enhances the warm sea surface temperature (SST) anomalies associated with the El Nio ***,the effects of interannually variable salinity are much more significant during the CP-El Nio than during the eastern Pacific (EP) El Nio,indicating that the salinity effect might be an important contributor to the development of CP-El Nio events.

关键词： salinity effect CP-E1.Nifio EN3 dataset

A baroclinic typhoon model with a moving multi-nested grid and variational adjustment initialisationI. Numerical method

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 1999年第4期18卷 191-201页

作者： Wu Huiding Yang Xuelian Bai Shan and Li Guoqing 1. national Marine {1. forecasting Centre, State Oceanic Administration, beijing 1.0081. China 2. Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John’ s, national Marine {1. {2. Centre Beijing 100081 China Department of Physics and Physical Oceanography Memorial University of Newfoundland St. John's NF A1B 3X7 Canada

A baroclinic typhoon model with a moving multi--nested grid is applied in marine environmental forecasts. This paper describes the numerical methods of the model including governing equations, finite differencing, spl... 详细信息

关键词： Typhoon model 3-dimensional baroclinic numerical method moving nested grid

同方期刊数据库

Low-frequency variability of the North Equatorial Current bifurcation in the past 40 years from SODA

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2011年第3期30卷 14-19页

作者： MENG Qingji WANG Fan LIU Na Key Laboratory of Ocean Circulation and Waves （KLOCAW） Chinese Academy of Sciences Qingdao 266071 China Graduate School of Chinese Academy of Sciences Beijing 100039 China national Marine {1. {2. center Beijing 100081 China

The low-frequency variability of the North Equatorial Current （NEC） bifurcation during 1.58 to 2.01.was investigated with the Simple Ocean Data Assimilation （SODA） 2.0.2.dataset. In agreement with recent observations, the NEC bifurcation latitude （NBL） shifted northward as depth increases, from about {2.7°N near the surface to about 1..1.N at depths around 500 m for the annual average. This study reveals that the interannual variations of NBL, with five years period, mainly focused on the upper 500 m with amplitude increasing as depth increased. The NBL shifted southward in the past 40 years, which was more significant in the subsurface at more than -0.02./a. The NBL manifests itself in the transports of NMK （NEC-Mindanao Current （MC）-Kuroshio） system in strong relationship with MC （0.7） and Kuroshio （-0.7）. The EOF analysis of meridional velocity off the Philippine coast shows that the first mode, explaining 62. of variance and 5 years period, was highly correlated with the southward shift of NBL with coefficient at about 0.75. The southward shift of NBL consists with the weakening of MC and strengthening of Kuroshio, which exhibited linear trends at -0.2.Sv/a and 0.1.Sv/a. Both interannual variation and trend of NBL were closely related to the variation of NMK system.

关键词： North Equatorial Current bifurcation latitude interannual variation linear trend NEC-Mindanao Current-Kuroshio system

Research on the multi-level intake water temperature effect of the Yalong River Jinping-I hydropower project

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2011年第S1期54卷 125-132页

作者： WU ShiYong 1.CAO Wei 1.WANG HongMei 1.SUN ShuangKe 2.&CHEN QiuWen 3 1.Ertan Hydropower Development Company,Ltd.,Chengdu 61.051.China 2.China Institute of Water Resources and Hydropower Research,{1. 1.0038,China 3 Research center for Eco-environmental Sciences,Chinese Academy of Sciences,{1. 1.0085,China 1. Ertan Hydropower Development Company Ltd. Chengdu 610051 China2. China Institute of Water Resources and Hydropower Research Beijing 100038 China3. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Based on the discussion of the multi-level intake application status of high dam reservoir,this paper takes the Jinping-I hydropower project reservoir in the Yalong River as an example,which is shaped by the highest 305 m high arch dam,and carries out the forecasting research on the reservoir temperature by numerical simulation and physical model *** paper studies the intake effect of withdrawing the surface warm water by the stoplog gates inlets and verifies the reliability of the mathematical model by comparative *** results show that for a high dam hydropower station,taking the appropriate multi-level intake measure can withdraw the surface warm water in the spawning season and provide a favorable environment for the fish *** technical ideas and implementation scheme are adopted in this *** can provide technical reference for the solutions of similar problems in the future and it also has important engineering significance on the research of water temperature in large deep reservoirs.

关键词： water temperature multi-level intake Jinping-I hydropower project

Vertical structure and seasonal variation of tidal and residual currents in the northern Huanghai Sea

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2011年第5期30卷 14-22页

作者： SONG Jun GUO Junru QIAO Lulu MU Lin YAO Zhigang LIU Yang LI Huan BAO Xianwen SUN Xiaoyan GAO Jia national Marine Data and Information Service State Oceanic Administration Tianjin 300171 China College of Physical and environmental Oceanography Ocean University of China Qingdao 266100 China Key Laboratory of Seafloor Science and Exploration Technology Ocean University of China Qingdao 266100 China national Marine {1. {2. center State Oceanic Administration Beijing 100081 China

Analysis of tidal current and sea level has been made based on the observations from the summer of 2.06 to the winter of 2.07,*** result indicates that a two-layer structure of residual current exists in summer,with its upper layer going northwestward and the lower layer *** addition,some strong residuals exist in the neighboring depth of the pycnocline during the current period of astronomical *** winter,except some individual layersthe residual currents mostly direct to the northwest,from which we can see the fluctuation of abnormal sea-level and the appearance of associated current because of the changes of the wind *** analysis of tidal ellipse indicates that the direction of the maximum semidiurnal component is clockwise from summer to winter,with an angle of ***,in summer the semidiurnal component rotates with depth clockwise while the diurnal component ***,the vertical structure is almost homogeneous in winter.

关键词： northern Huanghai Sea residual current tidal wave low-pass filtering