检索结果-南通市图书馆

Teleconnection between the Indian summer monsoon onset and the Meiyu over the Yangtze River Valley

在线全文

学校读者我要写书评

暂无评论

Science China Earth sciences 2008年第7期51卷 1021-1035页

作者： LIU YunYun1,2.3.& DING YiHui2.1 Chinese academy of {3. {2.,{3., China 2.National Climate Center,{3., China 3.Graduate University of Chinese academy of {2., beijing 100049, China 1. Chinese academy of meteorological {2. Beijing 100081 China 2. National Climate Center Beijing 100081 China 3. Graduate University of Chinese academy of sciences Beijing 100049 China

Based on the Indian and Chinese precipitation data and the NCEP-NCAR reanalysis circulation data, the relationship between the Indian summer monsoon (ISM) onset and the Meiyu over the Yangtze River Valley has been discussed by the methods of correlation analysis and composite analysis. The results show that the date of ISM onset over Kerala in the southwestern coast of the Indian Peninsula is about two weeks earlier than the beginning of the Meiyu over the Yangtze River Valley. After the outbreak of ISM, the teleconnection mode sets up from the western coast of India via the Bay of Bengal (BOB) to the Yangtze River Valley and southern Japan. It is different both in time and space from the telecon- nection mode which is from the northwest of India via the Tibetan Plateau to northern China. The for- mer mode is defined as the "south" teleconnection of the Asian summer monsoon, forming in the pe- riod of ISM onset; while the latter mode is called the "north" teleconnection, mainly occurring in the Asian monsoon culminant period. During the process of the "south" teleconnection’s formation, the Asian monsoon circulation has experienced a series of important changes: ISM onset, the northward movement of the south Asia high (SAH), the onset vortex occurrence, the eastward extension of the stronger tropical westerly belt, and the northeastward jump of the western Pacific subtropical high (WPSH), etc. Consequently, since ISM sets up over Kerala, the whole Asian continent is covered by the upper SAH after about two weeks, while in the mid- and lower troposphere, a strong wind belt forms from the Arabian Sea via the southern India, BOB and the South China Sea (SCS), then along the western flank of WPSH, to the Yangtze River Valley and southern Japan. With the northward moving of the subtropical jet streams, the upper westerly jet stream and the low level jet have been coupled ver- tically over east Asia, while the Yangtze River Valley happens to locate in the ascending motion

关键词： Indian summer monsoon (ISM) the Meiyu over the Yangtze River Valley teleconnection mode

Possible mechanism of the effect of convection over Asian-Australian “land bridge” on the East Asian summer monsoon onset

在线全文

学校读者我要写书评

暂无评论

Science China Earth sciences 2006年第11期49卷 1223-1232页

作者： HE Jinhai1, WEN Min2. DING Yihui3.& ZHANG Renhe2.1. Jiangsu Key Laboratory of meteorological Disaster (KLME), Nanjing Institute of Meteorology, Nanjing University of Informa- tion Science and Technology, Nanjing 2.0044, China 2. State Key Laboratory of Severe Weather (LaSW), Chinese academy of meteorological {3., beijing 100081, China 3. National Climate Center, Chinese meteorological Administration, beijing 100081, China 1. Jiangsu Key Laboratory of meteorological Disaster (KLME) Nanjing Institute of Meteorology Nanjing University of Information Science and Technology Nanjing 210044 China 2. State Key Laboratory of Severe Weather (LaSW) Chinese Academy of Meteorological Sciences Beijing 100081 China 3. National Climate Center Chinese Meteorological Administration Beijing 100081 China

The Asian-Australian “land bridge” is an area with the most vigorous convection in Asian monsoon region in boreal spring, where the onset and march of convection are well associated with the onset of East Asian summer monsoon. The convection occurs over Indo-China Peninsula as early as mid-April, which exerts critical impact on the evolution of monsoon circulation. Before mid-April there are primarily sensible heatings to the atmosphere over Indo-China Peninsula and Indian Peninsula, so the apparent heating ratios over them decrease with height. However, after mid-April it changes into latent heating over Indo-China Peninsula due to the onset of convection, and the apparent heating ratio increases with height in mid- and lower troposphere. The vertical distribution of heating ratio and its differences between Indo-China Peninsula and Indian Peninsula are the key factors leading to the splitting of boreal subtropical high belt over the Bay of Bengal. Such mechanism is strongly supported by the fact that the evolution of the vertical heating ratio gradient above Indo-China Peninsula leads that of 850 hPa vorticity over the Bay of Bengal. Convections over Indo-China Peninsula and its surrounding areas further increase after the splitting. Since then, there is a positive feedback lying among the convective heating, the eastward retreat of the subtropical high and the march of monsoon, which is a possible mechanism of the advance of summer monsoon and convection from Indo-China Peninsula to South China Sea.

关键词： Asian-Australian 'land bridge', tropical convection, Indo-China Peninsula, the splitting of boreal subtropical high belt, East Asian summer monsoon onset.

Relationship between the Asian-Pacific oscillation and the tropical cyclone frequency in the western North Pacific

在线全文

学校读者我要写书评

暂无评论

Science China Earth sciences 2008年第3期51卷 380-385页

作者： ZHOU BoTao1, CUI Xuan2.& ZHAO Ping3.1 Laboratory for Climate Studies, National Climate Center, China meteorological Administration, beijing 100081, China 2.National meteorological Center, China meteorological Administration, beijing 100081, China 3.Chinese academy of meteorological sciences, China meteorological Administration, beijing 100081, China 1. Laboratory for Climate Studies National Climate Center China Meteorological Administration Beijing 100081 China 2. National meteorological Center China Meteorological Administration Beijing 100081 China 3. Chinese academy of meteorological {2. China Meteorological Administration Beijing 100081 China

The relationship between the Asian-Pacific oscillation (APO) and the tropical cyclone frequency over the western North Pacific (WNP) in summer is preliminarily investigated through an analysis of ob- served data. The result has shown clearly that APO is significantly and positively correlated to the tropical cyclone frequency in the WNP. If APO is above (below) the normal in summer, more (less) tropical cyclones will tend to appear in the WNP. The present study also addresses the large-scale at- mospheric general circulation changes underlying the linkage between APO and the WNP tropical cy- clone frequency. It follows that a positive phase of summer APO is concurrent with weakened as well as northward and eastward located western Pacific subtropical high (WPSH), low-level convergence and high-level divergence, and reduced vertical zonal wind shear in the WNP, providing favorable envi- ronment for the tropical cyclone genesis, and thus more tropical cyclones will come into being, and vice versa.

关键词： Asian-Pacific oscillation western North Pacific tropical cyclone atmospheric circulation

Two possible mechanisms for vortex self-organization

在线全文

学校读者我要写书评

暂无评论

Science China Earth sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2. ZHOU Xiuji1 & GAO Shouting3.1. Chinese academy of meteorological {2.,{3., China 2. Department of Space Information Science, Nanjing University of Information Science and Technology, Nanjing 2.0044, China 3. Institute of Atmospheric Physics, Chinese academy of {2., beijing 10002., China 2. Department of Environmental Science Nanjing University of Information Science and Technology Nanjing 210044 China 1. Chinese academy of meteorological {2. Beijing 100081 China 3. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

A comparative analysis on two solar proton events

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2007年第1期52卷 47-51页

作者： LE GuiMing1,2.3.4, HAN YanBen2.& ZHANG YiJun3.1 Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites, China meteorological Administration,{3., China 2.National Astronomical Observatories, Chinese {2. of {3., beijing 100012. China 3.Chinese {2. of meteorological {3., China meteorological Administration,{3., China 4 National Center for Space Weather, China meteorological Administration,{3., China Key Laboratory of Radiometric Calibration and Validation for EnvironmentalSatellites China Meteorological Administration Beijing 100081 China

This paper presents a comparative analysis on the two Solar Proton Events (SPE), which occurred on 14 July 2.00 (Bastille Day) and 2. October 2.03.(2.OCT03. respectively. It is found that although the peak flux of the latter seemed to be greater than that of the former based on geostationary observations, the maximum intensities of the energetic protons (>10 MeV and 3. MeV) during the Bastille Day event were all higher than those of the 2.OCT03.event according to the interplanetary observations. Further analysis indicated that the quantity of the seed particles, which could be accelerated to the energies exceeding 10 and 3. MeV by the Coronal Mass Ejection (CME)-driven shock on 14 July 2.00, was far larger than that of the 2.OCT03.event. In the Bastille Day case, when the CME approached to the height around 14 R⊙, the CME-driven shock would reach its maximum capacity in accelerating the solar en- ergetic protons (>100 MeV). In contrast, on 2. October 2.03. when CME approached to the height about 58R⊙, the CME-driven shock reached its highest potential in accelerating the solar energetic protons of the same category. At this moment, the peak flux (>100 MeV) was about 155 pfu, which was much lower than 3.5 pfu measured on 14 July 2.00. This demonstrated that in the Bastille Day event, the quantity of the seed particles, which could be accelerated to the energy beyond 100 MeV, was significantly larger than its counterpart in the 2.OCT03.case. Therefore, the peak flux of an SPE event depends not only on the interplanetary intensity of the solar energetic particles, but also on the velocity of the associated CME-driven shock, and the quantity of the seed particles as well as on the interplanetary magnetic en- vironment. This paper also reveals that the magnetic sheath associated with ICME on 2. October 2.03.captured a large number of solar energetic protons, including those having energy greater than 100 MeV.

关键词：太阳质子 CME 太阳耀斑太阳系

Application of the moist vorticity vector in the analysis of a heavy rainfall event in North China

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2007年第12期17卷 1457-1465页

作者： Zhao Yu1,2.3. Wang Jianguo4 and Xue Deqiang2.1. Laboratory of Cloud-Precipitation Physics and Severe Storms, Institute of Atmospheric Physics, Chinese academy of {3., {2. 10002., China 2. Shandong Provincial {3. Observatory, Jinan 2.003., China 3. Graduate University of Chinese academy of {3., {2. 10003., China 4. Shandong Provincial {3. Bureau, Jinan 2.003., China) Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Shandong Provincial meteorological Observatory Jinan 250031 China Graduate University of Chinese academy of sciences Beijing 100039 China Shandong Provincial meteorological Bureau Jinan 250031 China

The moist vorticity vector (MVV), defined as (ζa×▽qv)/ρ introduced by Gao et al. is used to study a heavy rainfall event in North China. The MVV has zonal, meridional and vertical components in a three-dimensional framework. Analysis of domain-mean and mass-integrated quantities shows that the variation of the vertical component of the MVV closely follows the variation of the cloud hydrometeors, with a linear correlation coefficient of 0.95, indicating that the vertical component of the MVV is strongly associated with midlatitude convection. Further analysis shows that the vertical component of the MVV reflects the interaction between the horizontal vorticity and the horizontal specific humidity gradient, which can associate dynamic and thermodynamic processes with cloud microphysical processes. Thus, this study can help to understand how the interaction between circulations and clouds aids the development of convection, and the MVV can be used to trace the development and evolution of heavy rainfall.

关键词： moist vorticity vector heavy rainfall modeling study.

Persistent anomalous flows over the subtropical western Pacific insummer

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第8期43卷 672-675页

作者： ZHUANG Shiyu\+1 and JI Liren\+2.1. National meteorological Centre, China meteorological Administration,{2., China 2. LASG, Institute of Atmospheric Physics, Chinese {3. of sciences, beijing 100080, China National meteorological Ccntre China Meteomlcgical Administration Beijing China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The distribution of global persistent anomalies shows that the subtropical western Pacific is a key region with high_frequency occurrence of persistent anomalies. Analyses of streamfunction anomalies, OLR anomalies etc. suggest that the convective heating related to Indian monsoon might be responsible for the development of WPA. The results of numerical experiment by two linear barotropic models support the observation.

关键词： persistent anomalies subtropical high Indian monsoon anomalous forcing.

The onset and advance of the Asian summer monsoon

在线全文

学校读者我要写书评

暂无评论

Science Bulletin 2006年第1期51卷 80-88页

作者： Lü Junmei1,2.4, ZHANG Qingyun1, TAO Shiyan1 & JU Jianhua3.1. State Key Laboratory of Numerical Modeling for Atmospheric Sci- ences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese academy of sciences, {2. 10002., China 2. Department of Atmospheric sciences, Yunnan University, Kunming 650091, China 3. China meteorological Administration Training Centre, beijing 100081, China 4. Graduate School of Chinese academy of sciences, {2. 10003., China State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric sciences Yunnan University Kunming 650091 China Graduate School of Chinese academy of sciences Beijing 100039 China China meteorological Administration Training Centre Beijing 100081 China

Based on the daily outgoing longwave radiation (OLR) data from National Oceanic and At- mospheric Administration (NOAA) satellites, the Cli- mate Prediction Center’s merged analysis of pre- cipitation (CMAP) data and the National Centers for Environmental Prediction/National Center for At- mospheric Research (NCEP/NCAR) reanalysis dataset, the mean intraseasonal variability of the Asian summer monsoon (ASM) is investigated by using power spectrum analysis, band-pass filter, and diagnostic analyses. The processes of the onset and advance of monsoon over the southern part of Indo- china Peninsula, the east coast of Bay of Bengal, the South China Sea and the Indian subcontinent are explored. It is found that there is an abrupt change in OLR, precipitation and zonal wind during the onset and advance of the ASM. It is also indicated that the southern part of Indochina Peninsula and the adja- cent Andaman Sea is the region where the earliest onset of the ASM occurs in the 2.d pentad of May.

关键词： Asian summer monsoon intraseasonal variability onset advance.

Simulated seasonal movement of precipitation zone in rainy season over China and its change on CO_2.doubling

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental sciences 1993年第2期5卷 150-157页

作者： Cao HongxingChinese academy of meteorological {2.,{3., China Chinese academy of meteorological {2. Beijing 10081 China. China

In this paper, an investigation of simulated monthly precipitations from April to September is made. Though the precipitations are sometimes overestimated or underestimated, the geographical advance and recession of precipitation zones are well simulated by the UKMO global climate model with a simple mixed-layer ocean. Main characteristics of large-scale precipitation distribution are changed less on CO2.doubling, but the change is significant in some regions. The change in precipitation threatens us while the dry region is imposed by rainfall defect or the wet region by abundant rainfall induced by CO2.doubling.

关键词： greenhouse effect carbon dioxide change climate simulation.