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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 {2., Beijing 100081,china 2. Chinese Academy of meteorological Sciences, Beijing 100081, china 1. national meteorological {2. 100081 Beijing China 2. Chinese Academy of meteorological 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.

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,{2. meteorological administration,Beijing 100081,{2. 2.Nansen-Zhu International Research center,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 10002.,{2. 3 national meteorological center,{2. meteorological administration,Beijing 100081,{2. 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 {2. 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

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,{2., Beijing 100081, 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.

Predictor-based error correction method in short-term climate prediction

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Progress in Natural Science:Materials International 2008年第1期18卷 129-135页

作者： Hongli Ren Laboratory for Climate Studies,national Climate center,{2. meteorological administration,Beijing 100081,{2. Laboratory for Climate Studies National Climate Center China Meteorological Administration Beijing 100081 China

In terms of the basic idea of combining dynamical and statistical methods in short-term climate prediction,a new prediction method of predictor-based error correction(PREC)is put forward in order to effectively use statistical experiences in dynamical ***- yses show that the PREC can reasonably utilize the significant correlations between predictors and model prediction errors and correct prediction errors by establishing statistical prediction ***,the PREC is further applied to the cross-validation experiments of dynamical seasonal prediction on the operational atmosphere-ocean coupled general circulation model of china meteorological Admin- istration/{2. Climate center by selecting the sea surface temperature index in Ninflo3 region as the physical predictor that represents the prevailing ENSO-cycle mode of interannual variability in climate *** is shown from the prediction results of summer mean circulation and total precipitation that the PREC can improve predictive skills to some *** the PREC provides a new approach for improving short-term climate prediction.

关键词： Short-term climate prediction Seasonal prediction Predictor Error correction

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 {2., Guangzhou 510080, china 3 Chinese Academy of meteorological Sciences, Beijing 100081, china 4 national Climate {2., 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 meteorological 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

Multitime scale variations of sea surface temperature in the china seas based on the HadISST dataset

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Acta Oceanologica Sinica 2011年第4期30卷 14-23页

作者： JIN Qihua WANG Hui Chinese Academy of meteorological Sciences China Meteorological Administration Beijing 100081 China national Marine Environmental Forecasting center State Oceanic Administration Beijing 100081 China

The variability of the sea surface temperature（SST） in the china seas has been studied in seasonal,interannual and interdecadal scales based on the monthly data of HadISST spanning from 1870 to 2.07. The main results obtained are SST in the china offshore changes most actively at the seasonal scale with the intensity diminishing from north to south,as the temperature differences between summer and winter reaching 17 and 4 C in the northern and southern areas,respectively. Moreover,seasonal variation near the coastal regions seems relatively stronger than that far from the coastline;significant interannual variations are detected,with the largest positive anomaly occurring in 1998 in the overall area. But as far as different domains are concerned,there exists great diversity,and the difference is also found between winter and summer. Differed from the seasonal variations,where the strongest interannual variability takes place,resides to the south of that of the seasonal ones in the northern section,nevertheless in the South china Sea,the most significant interannual variability is found in the deep basin;interdecadal changes of summer,winter and annual mean SST in different domains likewise present various features. In addition,a common dominant warming in recent 2. a are found in the overall china offshore with the strongest center located in the vicinity of the Changjiang Estuary in the East china Sea,which intensifies as high as 1.3 C during the past 130 a.

关键词： china seas sea surface temperature multitime scale variations

Ocean color products retrieval and validation around china coast with MODIS

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Acta Oceanologica Sinica 2010年第4期29卷 21-27页

作者： SUN Lingt GUO Maohua WANG Xiaomei Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites China Meteorological Administration （LRCVES/CMA） National Satellite Meteorological Center China Meteorological Administration Beijing 100081 China national Satellite Ocean Application Service State Oceanic Administration Beijing 100081 China

Waters along china coast are very turbid with high concentrations of suspended sediment nearly all the time,especially at the Hangzhou Bay,the Changjiang （Yangtze） River Estuary and the shoal along Jiangsu *** these turbid and optically complex waters,the standard MODIS ocean color products tend to have invalid *** the water-leaving radiances in the near-infrared （NIR） are significant resulting from the strong scattering of suspended particles,the standard MODIS atmospheric correction algorithm often gets no results or produces significant *** because of the complex water optical properties,the OC3 model used in the standard MODIS data processing tends to get extremely high chlorophyll-a （Chl-a） *** this paper,we present an atmospheric correction approach using MODIS short wave infrared （SWIR） bands based on the fact that water-leaving radiances are negligible in the SWIR region because of the extreme strong absorption of water even in turbid waters.A regional Chl-a concentration estimation model is also constructed for MODIS from in situ *** algorithms are applied to MODIS Aqua data processing in the china coastal *** situ data collected in the Yellow Sea and the East china Sea in spring and autumn,2.03 are used to validate the *** good results have been *** is noted that water-leaving reflectance in the NIR bands are significant in waters along the china coast with high sediment *** satellite derived and in-situ reflectance spectra can match in the turbid waters along china coast,and there is relatively good linear relationship between satellite derived and in-situ *** RMSE value of Rrs（λ） is 0.0031 sr ？1 for all the nine ocean color bands （412.to 869 nm）.The satellite-derived Chl-a value is in the reasonable range and the root mean square percentage difference is 46.1%.

关键词： ocean color atmospheric correction chlorophyll-a MODIS china coastal region validation

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), Chinese Academy of meteorological Sciences, 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.

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