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An integrated decision method for prediction of tropical cyclone movement by using genetic algorithm

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Science china Earth sciences 2005年第3期48卷 429-440页

作者： YANG Yuanqin1 & WANG Jizhi2.1. National meteorological Center, beijing 100081,{2. 2. chinese academy of meteorological sciences, beijing 100081, {2. 1. National meteorological Center 100081 Beijing China 2. chinese academy of {2. sciences 100081 Beijing China

In this study an integrated decision method for the multi-prediction results of tropical cyclone movements by using genetic algorithm (GA) has been adopted. A genetic learning artifi- cial neural network (GLANN) as a learning mechanism for track prediction was developed through training with the huge samples of typhoon tracks from 1884 to 2.02. The prediction of typhoon motion is to consider how to suit the dynamic change of environment, where typhoon passed through. The neural network structure is described by GA. A fitness function for choice of GA is given to approach the maximum of fitness (the minimum of the errors). Parallel comparing analyses for prediction abilities of unusual typhoon tracks in recent years by GLANN with multi-forecast methods were conducted. More types of cases were employed in the comparing analyses, which consist of the typhoon, Winnie, No.11, in 1997, characterized by a long life over the ocean and in the mainland with severe effect on china, the 10 unusual typhoon tracks in the 1990s, the tracks with landfall and affected action in 1998 and the typhoons born in the Northwestern Pacific and the South china Sea in 2.00, including the 2.—48 h forecast, etc. The results indicated that for prediction ability of typhoon tracks, specially for unusual typhoons, GA decision-making developed in this study is superior to the others.

关键词： genetic algorithm, integrated decision, prediction of tropical cyclone.

Persistent anomalous flows over the subtropical western Pacific insummer

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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 academy 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.

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

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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 {2. sciences, beijing 100081, china 2.National Climate Center, beijing 100081, china 3 Graduate University of chinese academy of sciences, beijing 100049, china 1. chinese academy of {2. sciences Beijing 100081 China 2. National Climate Center Beijing 100081 China 3. Graduate University of chinese academy of {2. 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

Climatic change and urbanization effect in china

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Journal of Environmental sciences 1993年第1期5卷 23-29页

作者： Zhao Zongci academy of meteorological Science, State meteorological administration, beijing 100081, china academy of meteorological Science State Meteorological Administration Beijing 100081 China. China

Climatic change and urbanization effect in china during the last 39 years were investigated. It is found that a warming of about 0.2.℃ for the annual temperature has been noticed from 1951 to 1989. The warmings of about 0.78 ℃ in winter and 0.34 3℃ in spring have been shown. It is also presented that a cooling of about -0.2.℃ in summer has been indicated. The bigger cities are warmer than smaller cities in china. The dried trends in the annual precipitation during the last 39 years were presented. The precipitation decreased obviously in summer all over china. The bigger cities were drier than smaller cities.

关键词： climatic change urbanization effect global warming.

A comparative analysis on two solar proton events

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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, beijing 100081, {2. 2.National Astronomical Observatories, chinese academy of sciences, beijing 100012. {2. 3 chinese academy of meteorological sciences, china meteorological administration, beijing 100081, {2. 4 National Center for Space Weather, china meteorological administration, beijing 100081, {2. 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 30 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 30 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 355 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

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

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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), {2. academy of meteorological sciences, beijing 100081, china 3. National Climate Center, {2. 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.

Sea surface temperature east of Australia:A predictor of tropical cyclone frequency over the western North Pacific?

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chinese Science Bulletin 2011年第2期56卷 196-201页

作者： ZHOU BoTao 1,2.& CUI Xuan 3 1 National Climate Center,china meteorological {2.,beijing 100081,china 2.Nansen-Zhu International Research Center,Institute of Atmospheric Physics,chinese academy of sciences,beijing 10002.,china 3 National meteorological Center,china meteorological {2.,beijing 100081,china National Climate Center China Meteorological Administration Beijing China Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China National meteorological Center China Meteorological Administration Beijing China

The relationship between sea surface temperature (SST) east of Australia and tropical cyclone frequency over the western North Pacific (WNPTCF) is analyzed by use of observation *** WNPTCF from June to October is correlated negatively to spring SST east of *** the spring SST is in the positive phase,a cyclonic circulation anomaly in the upper troposphere and an anticyclonic circulation anomaly in the lower troposphere prevail over the western North Pacific from June to October,concurrent with an anomalous atmospheric subsidence and an enlarged vertical zonal wind *** conditions are unfavorable for tropical cyclone genesis,and thus WNPTCF *** negative phase of the spring SST east of Australia leads to more tropical cyclones over the western North *** spring SST east of Australia may give rise to simultaneous change in tropical atmospheric circulation via the teleconnection wave train,and then subsequently affect atmospheric circulation variation over the western North Pacific.

关键词：热带气旋北太平洋澳大利亚西部海面温度热带大气环流预测频率

Multiple time scale evaluation of the energy balance during the maize growing season,and a new reason for energy imbalance

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Science china Earth sciences 2009年第1期52卷 108-117页

作者： GUO JianXia1,2.BIAN LinGen3 & DAI YongJiu2.1 meteorological Observation Center of china meteorological administration,{2. 100081,china 2.State Key Laboratory of Remote Sensing Science,School of Geography and Remote Sensing Science,{2. Normal University,{2. 100875,china 3 chinese academy of meteorological sciences,{2. 100081,china meteorological Observation Center of china meteorological administration Beijing 100081 China State Key Laboratory of Remote Sensing Science School of Geography and Remote Sensing Science Beijing Normal University Beijing 100875 China

Energy imbalance is a common problem associated with the measurement of surface energy using the eddy covariance *** the evaluation of the energy balance,people usually pay more attention to the statistical result that the effective energy(the sum of sensible and latent heat) is systematically lower than the available energy(the difference of net radiation and ground heat flux).However,little attention has been paid to the existence of the reversed situation when the effective energy is larger than the available energy or their contribution to the overall energy closure *** this paper,based on the analysis of the energy balance on multiple time scales across the maize growth season,we conclude that the non-synchronization of energy components is the main reason for the existence of the reversed *** shifting the phase of the effective energy components half an hour ahead,the rates of energy closure over all time scales are improved and dramatically reduce the number of the half-hourly samples when the energy ratio exceeds 1 or is below *** to the characteristics of the energy distribution and transformation over multiple time scales,latent heat is always the main type of energy cost,and the residual of the energy balance increases with the growth of the maize plant surpassing the sensible heat for seventy *** is suggested that the heat storage and photosynthetic energy play an important role in the energy balance during the growing period of maize.

关键词： maize energy balance multiple time scale energy hysteresis

Simulation of 1991-2.05 Meiyu seasons in the Yangtze-Huaihe region using BCC_RegCM 1.0

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chinese Science Bulletin 2010年第11期55卷 1077-1083页

作者： HU YaMin1,2.3& DING YiHui4 1 Institute of Tropical and Marine Meteorology, china meteorological administration, Guangzhou 510080, china 2.Guangdong Climate Center, Guangzhou 510080, china 3 chinese academy of meteorological sciences, beijing 100081, china 4 National Climate Center, china meteorological administration, beijing 100081, china Institute of Tropical and Marine Meteorology China Meteorological Administration Guangzhou 510080 China Guangdong Climate Center Guangzhou 510080 China chinese academy of {2. sciences Beijing 100081 China National Climate Center China Meteorological Administration Beijing 100081 China

By using BCC_RegCM 1.0 (RegCM for short) from beijing Climate Center (BCC), china meteorological administration (CMA), the Meiyu season characters over the Yangtze-Huaihe region during 1991-2.05 are simulated. The major conclusions of this study may be summarized as the following: (1) RegCM can reproduce the interannual variation and the spatial distribution of the summertime precipitation and temperature in the Yangtze-Huaihe region. (2. By use of a generalized Meiyu criterion and in accordance with model-calculated precipitation and temperature, the Meiyu onset and ending date have been determined. Compared with the observation, RegCM can simulate the interannual variation of the Yangtze-Huaihe Meiyu with preferable capability for most of the normal Meiyu years (such as 1995, 1997, 2.00, 2.01, 2.02.and 2.04), especially for the rich Meiyu years of 1996, 1998 and 1999. (3) In terms of the average simulation for the recent 15 years, the timings of onset and ending of Meiyu occur on June 1 and July 13, respectively, which are earlier than the climatological observation. For duration, Meiyu persists for 32.d, 3 d shorter than the observation. The index of Meiyu intensity is 2.45, while the climatological one is 3.00. Therefore, RegCM is capable of simulating the climatological Meiyu duration and intensity, while the capability of simulating the onset and ending date of Meiyu still needs to be improved.

关键词：梅雨季节模拟计算长江气候观测发病时间强度指数中国气象局空间分布