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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, china 2 national Astronomical Observatories, Chinese Academy of Sciences, beijing 100012, china 3 Chinese Academy of Meteorological Sciences, china Meteorological Administration, beijing 100081, china 4 national center for Space Weather, china Meteorological Administration, beijing 100081, china Key Laboratory of Radiometric Calibration and Validation for environmental Satellites China Meteorological Administration Beijing China national Astronomical Observatoires Chinese Academy of Sciences Beijing China Chinese Academy of Meteorological Sciences China Meteorological Administration Beijing China

This paper presents a comparative analysis on the two Solar Proton Events (SPE), which occurred on 14 July 2000 (Bastille Day) and 28 October 2003 (28OCT03) 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 28OCT03 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 2000, was far larger than that of the 28OCT03 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 28 October 2003, 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 2000. 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 28OCT03 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 28 October 2003 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

Evaluation of potential hazards from teletsunami in china:Tidal observations of a teletsunami generated by the Chile 8.8 M_w earthquake

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Chinese Science Bulletin 2011年第11期56卷 1108-1116页

作者： YU FuJiang YUAN Ye ZHAO LianDa WANG PeiTao national marine environmental forecasting center Beijing 100081 China

At 14:34 beijing time on February 27,2010,an earthquake of M w 8.8 rocked the central coast of Chile.A teletsunami was triggered by the huge earthquake and then propagated across the entire Pacific in less than 24 *** initial tsunami wave arrived at the southeast coast of china at 16:20 on February 28 and was recorded in real time by a number of tidal gauges off china's Mainland and Taiwan *** teletsunami waves have never been recorded with such a broad geographical scope in china before this *** aim of the present work is to report the first description of sea-level oscillations generated by the Chile tsunami,and evaluate the potential hazards that teletsunami poses to the coast of *** results reveal that the east coast of Taiwan Province,Zhejiang Province and the north coast of Fujian Province are vulnerable to transoceanic *** addition,spectral and wavelet analysis of the recorded sea-level oscillations shows that "seiches" are easily excited by the resonance resulting from the interaction between the initial tsunami waves and local geometry (such as semi-enclosed bays and ports).The superimposition of the two oscillations would amplify the wave height further.

关键词：中国大陆 8级地震潮汐观测智利评估危险东南沿海实时记录

NEW WIND WAVE GROWTH RELATIONS

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Journal of Hydrodynamics 2004年第5期16卷 608-614页

作者： WUShu-ping HOUYi-jun YINBao-shu InstituteofOceanology ChineseAcademyofSciencesQingdao266071China

In the present paper combining the relationship between wave steepness andwave age with the significant wave energy balance equation for wind wave, a new wind wave growthrelation is presented. Comparisons with the other existing wind wave growth relations show that theresults in present paper accord better with the wind wave growth process.

关键词： relationship between wave steepness and wave age wind wave energy balanceequation new wind wave growth relation

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,china 2. Chinese Academy of Meteorological Sciences, beijing 100081, china national Meteorological center Beijing China Chinese Academy of Meteorological Sciences 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 2002. 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 2000, including the 24—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.

The　concentration　of　total　dissolved　CO_2　in　surface　water　in　ENSO　event──The　results　of　investigation　during　TOGA　expeditions

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Acta Oceanologica Sinica 1995年第2期14卷 208-224页

作者： Ma Liming Zhang Bin and Qiao Ran (national Research center for marine environmental Forecasts, State Oceanic Administration, beijing 100081, china)

The observations of total dissolved CO2 (TCO2) in surface water on the range from 115°E to 165°E,from 10°S to 20°N from Dec. 1986 to Jun. 1990, present following results: There was distinguished difference of distribution of TCO2 between during El Nino and La Nina, especially on east of 155° E and equator. During El Nino TCO2 was the lowest (TCO2, 1 900 μmol/kg) in seven cruises and proportional to salinity, the dominant effect of current was from North Equatorial Current (NEC). During La Nina the value of TCO2 became the highest (TCO2 >1 900 μmol/kg) in range of Equatorial Upwelling, the dominant effect was from South Equatorial Current. The effect of air-sea exchange and biological activity increased. The types of distribution and interannual variations of TCO2 in 110 single stations and 23 small areas, the characteristics of relationship among TCO2, PCO2, S, SST during El Nino and La Nina are discussed in this *** above results it is clear that TCO2 is a useful observational quantity, which reflects the alteration of atmosphere-sea system and the change of surface currents, air-sea exchange and biological activity caused by this alteration.

关键词： ENSO event investigation

Solar release time of solar energetic particles and associated acceleration source in corona

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Chinese Science Bulletin 2008年第2期53卷 161-168页

作者： LE GuiMing1,2,3,4, TANG YuHua1 & HAN YanBen4 1 Department of Astronomy, Nanjing University, Nanjing 210093, china 2 Key Laboratory of Radiometric Calibration and Validation for environmental Satellites, china Meteorological Administration, beijing 100081, china 3.national center for Space Weather, china Meteorological Administration, beijing 100081, china 4 national Astronomical Observatories, Chinese Academy of Sciences, beijing 100012, china Department of Astronomy Nanjing University Nanjing China Key Laboratory of Radiometric Calibration and Validation for environmental Satellites China Meteorological Administration Beijing China national center for Space Weather China Meteorological Administration Beijing China national Astronomical Observatories Chinese Academy of Sciences Beijing China

Solar energetic particles (SEPs) are accelerated in corona at an early phase of solar energetic particle events (SEPE). The acceleration mechanism of SEPs in corona can only be inferred from an analysis of multi-band observational data, as the observation of SEPs is usually made around 1AU. In this context, people have investigated spectrums, charge state, solar release time (SRT), and multi-band data of SEPEs, in an attempt to judge the acceleration mechanism of SEPs. The SRT computation of SEPs is an important and commonly used approach to study the acceleration mechanism of SEPs in corona. This paper reviews some important findings concerning the SRT computation of SEPs, and analyzes different merits of each approach for such calculation, based on a range of SEPE case studies. This paper also analyzes and discusses both possible and actual acceleration mechanisms of a number of SEPEs, by calculating the SRT of the SEPEs. Finally, the paper summarizes the possible problems in studying an acceleration mechanism of SEPEs inferred from the SRT of SEP.

关键词：阳光释放时间加速度电晕太阳耀斑

Absolute radiometric calibration of CBERS-02 IRMSS thermal band

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Science china(Technological Sciences) 2005年第S2期48卷 72-90页

作者： ZHANG Yong1,2,3, GU Xingfa1,3,4, YU Tao1,3, ZHANG Yuxiang5, CHEN Liangfu1,3, LI Xiaoying1,2,3, LI Xiaowen1,3 & HE Liming6 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101, china 2. Graduate University of Chinese Academy of Sciences, beijing 100039, china 3. The center for national Spaceborne Demonstration, beijing 100101, china 4. Institut national de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. national Satellite Meteorological center, beijing 100081, china 6. State environmental Protection Administration, beijing 100029, china State Key Laboratory of Remote Sensing Science Beijing Normal University Chinese Academy of Sciences Beijing 100101 China Graduate University Chinese Academy of Sciences Beijing 100039 China center for national Spaceborne Demonstration Beijing 100101 China national Satellite Meteorological center Beijing 100081 China Institut national de la Recherche Agronomique Climat Sol Environnement 84914 Avignon France State environmental Protection Administration Beijing 100029 China

Based on the laboratory calibration before launch of CBERS-02 IRMSS thermal infrared channel, the onboard blackbody calibration, the radiometric cross- calibration against TERRA MODIS corresponding channel and the in-flight field calibration at Lake Qinghai: water surface radiometric calibration test site of china on Aug. 17, 2004 are carried out in this research. When making onboard blackbody calibration of CBERS-02 IRMSS, it is necessary to understand inside structures and light path in IRMSS camera and receive and process calibration blackbody signals at normal and high temperatures. Onboard blackbody calibration results of each detector are very important to relative radiometric calibration of images processing and absolute radiometric calibration of each detector. In-flight field calibration mainly contains field experiments, obtaining synchronous images, spectrum marching and MODTRAN radiative transmi- ssion computation. Radiometric cross-calibration of CBERS-02 IRMSS thermal band against TERRA MODIS selected 6 times synchronous images of two sensors passing through Lake Qinghai and Lake Taihu from August to December, 2004 to compute the cross calibration data. Combining the in-flight field calibration and radiometric cross calibration data, the absolute radiometric calibration coefficients are calculated by the linear regression method. This new calibration model can obviously control the radiometric calibration uncertainties aroused by the single point method used in the in-flight calibration of CBERS-02 IRMSS, this kind of sensors cannot receive the cosmic background radiation. In this research, the radiometric calibration coefficients obtained through the linear regression model are 8.53 (gain, unit: DN/W m?2sr?1μm?1) and 44.92 (offset, unit: DN).

关键词： CBERS-02 IRMSS thermal band in-flight field calibration onboard blackbody calibration cross calibration.

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

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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 environmental forecasting center Beijing 100081 China

The low-frequency variability of the North Equatorial Current （NEC） bifurcation during 1958 to 2001 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 12.7°N near the surface to about 17.1°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 -0.24Sv/a and 0.11Sv/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

INTERANNUAL VARIABILITY OF KUROSHIO CURRENT AND ITS EFFECT ON THE NEARSHORE BRANCH IN JAPAN/EAST SEA

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Journal of Hydrodynamics 2010年第3期22卷 305-311页

作者： ZHENG Pei-nan WU De-xing LIN Xiao-pei LI Xiao-ting Physical Oceanography Laboratory Ocean University of China Qingdao 266100 China marine environmental Ensuring center the Headquarters of General Staff Beijing 100081 China marine environmental Ensuring center the Headquarters of General Staff Beijing 100081 China

Based on the Hybrid Coordinate Ocean Model （HYCOM）, this article presents simulations of the three-dimensional dynamic and thermal structure of the North Pacific Ocean （NPO） in the time domain from January 1991 to December 2000. The baroclinic current field and its interannual variability in Northwest Pacific Ocean （NWPO）, especially, the Kuroshio Current （KC） and the Japan/East Sea （JES） are analyzed and discussed. The results show that the HYCOM covers a complete dynamic and thermo process with adequate representations of the eddy fields and variability in main spatial and temporal scales. The model is used to simulatethe strong interanual variability of the KC, which may affect the strength of the eastern bifurcation of the Tsushima Warm Current （TSWC）, named the Nearshore Branch （NB） in the JES. When the KC is strong and its axis is close to the Japan Island, the TSWC and its bifurcations in the JES would intensify accordingly. Our results confirm once again the hypothesis of Yang et al. that the KC determines the annual mean NB in the JES via the ＂island integral constraint＂. This article further extends this hypothesis to study the KC role in the NB on a time dependent scale.

关键词： KC JES NB HYCOM interannual variability island integral constraint