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Effects of 4DVAR with multifold observed data on the typhoon track forecast

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Chinese Science Bulletin 2003年第S2期48卷 93-98页

作者： WANG Yunfeng, WANG Bin, MA GANG & WANG Yushun 1. LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences. Beijing 100029, china: 2. national satellite {3. center, Beijing {5.. china Chinese Acad Sci Inst Atmospher Phys LASG Beijing 100029 Peoples R China Natl satellite Meteorol Ctr Beijing 100081 Peoples R China

Effects of 4-dimension variational data assimi-lation (4DVAR) with multifold observed data on the typhoontrack forecast are studied, by using the MM5.3.model, theRTTOVS-5.model and their adjoint models. The data usedfor assimilation include large-scale background fields data,bogus data, cloud-derived wind data, satellite inverse data,and high resolution infrared radiation sounder data (HIRS).There are 5.typhoon cases are used to perform the numericalexperiments and assimilation experiments. The numericalresults show that with 4DVAR the initial fields can be greatlyimproved and the initial typhoon structure can be clearlydescribed.

关键词： multifold observed data 4DVAR typhoon track. DOI: 10.13.0/03.d045.

On linking climate to Chinese dynastic change: Spatial and temporal variations of monsoonal rain

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Chinese Science Bulletin 2010年第1期55卷 77-83页

作者： ZHANG DeEr1, LI Hong-Chun2,3. KU Teh-Lung2,4 & LU LongHua5.1 national Climate center, Beijing {3., china 2 Department of Earth Sciences & Research center of Ocean Environment and Technology, Cheng-Kung University, Tainan 70101, Taiwan, china 3.School of Geographical Sciences, Southwest University of china, Chongqing 400715. china 4 Department of Earth Sciences, University of Southern California, Los Angeles, CA 90089, USA 5.Chinese Academy of meteorological Sciences, Beijing {3., china national Climate center Beijing China Department of Earth Sciences & Research center of Ocean Environment and Technology Cheng-Kung University Tainan Taiwan China School of Geographical Sciences Southwest University of China Chongqing China Department of Earth Sciences University of Southern California Los Angeles USA Chinese Academy of meteorological Sciences Beijing China

The causal correlation or linkage between the East Asian Monsoon (EAM) intensity and rise/fall of Chinese dynasties recently proposed by high-resolution paleoclimate reconstructions is examined in detail. Aside from many exceptions to the correlation, both instrumental and historical climate records show strong spatial variations of rainfall on annual-to-decadal scales over eastern china. The relationship between rainfall and EAM intensity also exhibits regional disparity. These observations suggest: (1) Tak-ing paleo-proxy records from a single locality in eastern china to imply changes in drought/wetness as to affect the cultural and political history of china is fraught with uncertainty. (2) On annual-to-decadal scales, the thesis that δ18O in speleothems can be used as a proxy for the EAM strength lacks empirical underpinnings.

关键词：古气候重建东亚季风强降雨时空变化中国东部地区连接 EAM 高分辨率

Comparison of the influence factors on NDVI for CCD camera and WFI imager on CBERS-02

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Science china(Technological Sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3. LI Xiaoying1,2,3. ZHANG Yong1,2,3. ZHAO Feng1,2,3. GU Xingfa1,3.4, ZHU Li1,2,3. WANG Pengxin5.& MIN Xiangjun6 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Application, CAS, Bei- jing 100101, china 2. Graduate University of Chinese Academy of Sciences, Beijing 10003., china 3. The {3. for national Spaceborne Demonstration, Beijing 100101, china 4. Institut national de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. College of Information and Electrical Engineering, china Agricultural University, Beijing 100083. china 6. china {3. for Resource satellite Data and Application, Beijing 10083., china State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Application CAS Beijing 100101 China

CCD and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NDVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCD and WFI sensors on NDVI. Results indicate that radiometric calibration is the most important factor on NDVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NDVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NDVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NDVI of WFI is higher than that of CCD. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCD WFI NDVI LAI.

Simulation of freezing and melting of soil on the northeast Tibetan Plateau

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Chinese Science Bulletin 2011年第20期56卷 2145-2155页

作者： XIA Kun 1,2,3.LUO Yong 2,4,5.& LI WeiPing 2 1 Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,china 2national Climate {3.,china meteorological Administration,Beijing {5.,china 3.raduate University of Chinese Academy of Sciences,Beijing 100049,china 4 {3. for Earth System Science,Tsinghua University,Beijing 100084,china 5.ey Laboratory of Earth System Numerical Simulation,Ministry of Education,Beijing 100084,china Institute of Atmospheric Physics Chinese Academy of Sciences national Climate center China Meteorological Administration Graduate University of Chinese Academy of Sciences center for Earth System Science Tsinghua University Key Laboratory of Earth

Using observational data spanning the period from February to December 2009 and recorded at the Suli station in Qinghai Province,the land-surface model CLM3.0 was employed to simulate the freezing and melting of *** results indicate that the simulated soil temperature is higher than the observed soil temperature and the ultimate thawing date is earlier than the observed date during the melting *** the freezing period,the simulated soil temperature is lower than the observed soil temperature and the ultimate freezing of the deep soil is earlier than that ***,the simulation of freezing is better than that of melting,and the simulation of a shallow layer is better than that of a deeper *** the original CLM3.0,it is assumed that frozen soil begins to melt when the soil temperature exceeds 0C,which is inconsistent with *** critical freeze-thaw temperature was calculated according to thermodynamics equations and the freeze-thaw condition was *** this work,the melting rate for frozen soil was reduced using the modified scheme,and the simulated soil temperature was lowered. Meanwhile,the refreezing of soil during the melting season was well simulated and more closely matched ***,it was found that the rates of melting and freezing differ,with the former being slower than the latter,but refreezing during the melting season is rather quick.

关键词：土壤温度冻结期青藏高原东北部模拟融化观测数据热力学方程表面模型

Numerical simulation of topography effects on the “00.7” severe rainfall in Beijing

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Progress in Natural Science:Materials International 2005年第9期15卷 818-826页

作者： ZHANG Chaolin1**, JI Chongping1, KUO Yinghwa2, FAN Shuiyong1, XUAN Chunyi3.and CHEN Min1(1. Institute of Urban Meteorology, china meteorological Administration, Beijing 100089, china 2. Mesoscale and Microscale Meteorology Division, {3. center for Atmospheric Research, Boulder, CO 803.7-3.00, USA 3. Beijing meteorological Bureau, Beijing 100089, china) Institute of Urban Meteorology China Meteorological Administration Beijing 100089 China. Mesoscale and Microscale Meteorology Division National Center for Atmospheric Research Boulder CO 80307-3000 USA. Beijing meteorological Bureau Beijing 100089 China

In an effort to study the severe rainfall event of 4—5.h July 2000 in Beijing (with 24h accumulated precipitation of 240 mm), we perform numerical simulations to investigate this event using the MM5.3.6 model. The model is initialized with the MM5.WRF 3.VAR analysis, which incorporates the ground-based GPS precipitable water vapor, automatic and conventional {3. observations in its assimilation step. For 24 h accumulated precipitation forecast, the threat scores are 0.72, 0.76, 0.67 and 0.63. for thresholds of 1, 5. 10, and 20 mm, respectively. Holding other factors unchanged, sensitivity experiments were conducted with different topographic resolutions of 110, 5. and 3.7 km to investigate the topographic effects on precipitation over the Beijing area. In these sensitivity experiments, we attempt to preserve the realistic orographic distribution in the model topography under the condition of keeping the dynamic-thermodynamic consistency of the initial model atmosphere to the extent possible. Results indicate that the unique topographic distribution and variations in the Beijing area play an important role in determining the location, distribution and intensity of heavy precipitation.

关键词： topography heavy rainfall 3.VAR ground-based GPS numerical simulation.

Detection of nighttime sea fog/stratus over the Huang-hai Sea using MTSAT-1R IR data

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Acta Oceanologica Sinica 2009年第2期28卷 23-35页

作者： GAO Shanhong WU Wei ZHU Leilei FU Gang HUANG Bin Physical Oceanography Laboratory Ocean University of China Qingdao 266003 China Shandong Provincial meteorological Institute Jinan 250031 China national meteorological center China Meteorological Administration Beijing 100081 China

A dual channel difference （DCD） method is applied to detect nighttime sea fog/stratus over the Huanghai Sea using the infrared （IR） data of shortwave （3.5.4.0 μm） and longwave （10.3.11.3.μm） channels from the Multi-functional Transport satellite （MTSAT）-IR, i.e., shortwave minus longwave brightness temperature difference （SLTD）. Twenty-four sea fog events over the Huanghai Sea during March to July of 2006 and 2007 are chosen to determine a suitable value of SLTD for nighttime sea fog/stratus detection, and it is found that the value of-5.5.2.5. can be taken as a criterion. Two case examples of sea fog events are especially demonstrated in detail utilizing the criterion, and the results show that the derived sea fog/stratus coverage is quite reasonable. This coverage information is very helpful to analyze the formation and evolution of sea fog/stratus during night and can provide sea fog researchers with observational evidences for model results verification. However, more efforts are needed to further obtain vertical extent information of sea fog/stratus and attempt to discriminate between sea fog and stratus.

关键词： Huanghai Sea nighttime sea fog MTSAT-1R dual channel difference method

Progress in china’s climate change study in the 20th century

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Journal of Geographical Sciences 2004年第S1期 5-13页

作者： ZHAI Panmao1,2, CHAO Qingchen1,2, ZOU Xukai1,2(1. Laboratory for Climate Studies, china meteorological Administration, Beijing 100081, china 2. national Climate {5., china meteorological Administration, Beijing 100081, china)

Studies on the 20th century climate change in china have revealed that under the background of global warming over the past century, climate in china has also experienced significant change with mean annual temperature increased by about 0.5.oC. More reliable results for the latter part of the 20th century indicate that the largest warming occurred in Northwest china, North china and Northeast china, and the warming in winter is most significant. Although no obvious increase or decrease trends were detected for mean precipitation over china in the past half century, regional differences are very distinct. In the middle and lower reaches of the Yangtze River, precipitation increased, while that in the Yellow River Basin markedly decreased. Studies suggest that climate change in china seems to be related not only with the internal factors such as ENSO, PDO, and the others, but also with the anthropogenic effects such as greenhouse gas emissions, and land use. The future climate change studies in china seem to be important in narrowing understanding the nature of china's climate change and its main causes, since it is significant for projection and for impact assessment of climate change in the future.

关键词： th century climate change china

A new type of Shipboard meteorological satellite Receiving-processing System

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Acta Oceanologica Sinica 2000年第1期19卷 35-46页

作者： Xie Simei Hao Chunjiang Zou Bin Jing Qiyi Liao Xiaohong Sheng Xiaowen Zhang Canrong (1. national Research center for Marine Environment Forecasts, Beijing 100081,{3. 2, Second Institute of{3. Aerospace Corporation 3. Beijing Chuanyi Electric Compan Natl. Res. Ctr. Mar. Environ. F. Beijing 100081 China Second Inst. of china Aerosp. Corp. China Beijing Chuanyi Electric Company Chinese Academy of Sciences Beijing China

The Shipboard meteorological satellite Receiving-processing System (SMSRPS) is specially developed for the navigation meteorological safeguard of the Antarctic exploration ship over the sea ice area of the forth Ocean. This system can suit to the climate environment of very high temperature high moisture and very low temperature - supersaturation; it has a self-protection ability to against the hurricane - force wind over force 12 and the strong vibration during icebreaking, as well as strong magnetic disturbance. It has two sets of receiving-imagery processing systems for polar orbit low-resolution and quasi-stationary high-solution satellites. The key creation Points of this system are as follows: 1. the active gyro-control stabilization platform and a mixed mounting system of three rotating a - B and x -- y axes are used. It solved the tracing difficulties both in the low elevation angle and very high elevation angle of polar-orbit satellite, even in the status of ship moving with continuously changing its poition, direction and ship roll and pitch. 2. Imagery processing subsystem. The newest BORLAND-- DELPHI language and PASCAL language pro gramming software are used under WINDOWS 95.environment. It has a dynamic positioning nested-grid system and electric mapping grid data system. It can show the latitude-longitude of any point on the map, and marks any object such as ship, station or island, and draws the route. It can monitor cloud and temperature, forest fire, anomalous change of ocean and land. It can output satellite cloud maps of 24 bit with very high clarity. This system is very advanced in technique for the whole structure with the features of small volume, light weight and very low cost. It suits to very bad climate and ocean environment. Its imagery process ing system has complete functions with high resolution and being very easy to operate. It is not only suit to land use, but also and specially to all kinds of ship over the sea. It can be exte

关键词： Shipboard meteorological satellite Receiving-processing System imagery processing system active gyro-control platform

Cloud Climatology Characteristics of china from ISCCP Data

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Cloud Climatology Characteristics of China from ISCCP Data