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Mineral provinces and material provenance of the surficial sediments near the Zhongsha Islands in the South china Sea

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Acta Oceanologica Sinica 2007年第1期26卷 66-76页

作者： YAN Quanshu1, 2. 3, SHI Xuefa2., WANG Kunshan2.. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 2.6071, china2. Key laboratory of Marine Sedimentology and Environment Geology of State Oceanic {2., First Institute of Oceanograghy, State Oceanic {2., Qingdao 2.6061, china3. Graduate School, Chinese Academy of Sciences, beijing 100049, china Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 First Institute of Oceanograghy State Oceanic Administration Key Laboratory of Marine Sedimentology and Environment Geology of State Oceanic Administration Qingdao 266061

Characteristics and distribution patterns of clastic minerals (0.063～0.12. mm) in bottom sediments represent a significant indicator for the identification of the origin of sediment. One hundred and fourteen surface sediment samples, which were collected from the area near the Zhongsha Islands in the South china Sea, were analysed to identify the mineral suites and their distributions in the study area. The area can be divided into three mineral provinces: (Ⅰ) a province of biogenic minerals, which mainly originate from the Zhongsha Atoll; (Ⅱ) a province of volcanogenic minerals, which are mainly derived from local basaltic seamounts and small-scale volcanoes that are probably erupting, with some influences from the island-arc volcanic region around the South china Sea; and (Ⅲ) a mixed mineral province whose material source includes biogenic minerals, volcanogenic minerals and terrigenous minerals; the last province can be subdivided into a mixed mineral sub-province of the northeastern part of the study area, in which terrigenous minerals are mainly derived from china’s Mainland and do not exceed 17°N, and a mixed mineral sub-province of the southeastern part of the study area, in which terrigenous minerals are derived from Kalimantan and Indochina Peninsula and might be further transported into the deep sea basin through submarine canyons.

关键词： South china Sea Zhongsha Islands light mineral minerals province material provenance

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Effect of non-spherical dust aerosol on its direct radiative forcing

Effect of non-spherical dust aerosol on its direct radiative...

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强化科技基础推进气象现代化——第2.届中国气象学会年会

作者： Zhili Wang a,Hua Zhang b,Xianwen Jing a,b,Xiaodong Wei c a Chinese Academy of meteorological Sciences,beijing {2.,china b laboratory for climate studies,National climate Center,china meteorological administration,beijing {2.,china c meteorological Center,East china Bureau of Air Control,Shanghai 2.1702.china

The optical properties of spherical and non-spherical dust aerosols are calculated using the Lorenz-Mie theory and the combination of T-matrix method and an improved geometric optics *** resulting optical properties are then applied in an interactive system that coupled a general circulation model with an aerosol model to quantitatively analyze the effect of non-spherical dust aerosol on its direct radiative forcing(DRF).Our results show that the maximum difference in dust instantaneous radiative forcing(IRF) between spherical and non-spherical particles is 0.2. W m-2.at the top of the atmosphere(TOA) and appears over the Sahara Desert due to enhanced absorption of solar radiation by non-spherical *** global annual means of shortwave(longwave) IRFs due to spherical and non-spherical dust aerosols at the TOA for all sky are-0.62.0.074) W m-2.and-0.61(0.073) W m-2.respectively,and the corresponding values for clear sky are-1.16(0.092. W m-2.and-1.14(0.093) W m-2.which indicates that the non-spherical effect of dust has almost no effect on their global annual mean ***,non-spherical dust displays more evident influences than above on its atmospheric-and land-temperature adjusted radiative forcing(ARF) at the TOA over the Saharan Desert,West Asia,and northern china,with an approximate maximum increase of 3.0 and decrease of 0.5 W *** global annual means of shortwave(longwave) ARFs due to spherical and non-spherical dust aerosols are-0.55(0.052. W m-2.and-0.48(0.049) W m-2.at the TOA for all sky,respectively,and the corresponding values for clear sky are-1.07(0.066) W m-2.and-0.95(0.062. W *** ARFs of dust become much weaker than their corresponding *** absolute values of annual mean ARF for non-spherical dust are approximately 13%(11.2.) and 6%(6%) less than those of spherical dust for the shortwave and longwave for all sky(clear sky),*** results indicate that the non-spherical effect of dust can reduce their ARFs more obvio

关键词： Dust Spherical/Non-spherical Particles IRF ARF

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Analyzing Precipitation Characters of South and North china Based on the Exponent of Scaling Law

Analyzing Precipitation Characters of South and North China ...

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中国数学力学物理学高新技术交叉研究会第11届学术研讨会

作者： Gong Zhi-qiang~1 Feng Guo-lin~2.Zhi Rong~2.Zhang Da-quan~2.1.Department of Physics Yangzhou University,Yangzhou 2.5009,china 2.laboratory for {2. studies,National {2. Center,china meteorological administration,beijing 100081,china

＜正＞In light of the recent research achievements of nonlinear science and in the context of the daily precipitation data from 1956 to 2.00 at 2. stations in south and north china compiled by the National climate Center,we calculated the exponents of power-law tail（EPT）on the cumulative distribution of probability of finding segment with lengths larger than l for each station’s precipitation time series based on BG algorithm, try to analyze the characters of precipitation both in south and north china from a new *** results show that power-law decay（scaling law）of the distribution of the stationary period may be a common occurrence for precipitation and other nonstationary time series;The distribution of EPT for precipitation might be different from area to area,and north china（NC）is comparing lager than south china（SC）;Meanwhile,The exponents of power-law tail（EPTs）might be another effective way to study the abrupt changes contained in nonlinear and nonstationary time series.

关键词： precipitation the exponent of power-law tail abrupt precipitation change grade

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Numerical study of sea waves created by tropical cyclone Jelawat

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Acta Oceanologica Sinica 2011年第5期30卷 64-70页

作者： LI Jie QIAN Hongbao LI hai LIU Yu GAO Zhiyi Key laboratory of Research on Marine Hazards Forecasting National Marine Environment Forecast Center State Oceanic Administration Beijing 100081 China Administrative Center for china＇s Agenda 2. Beijing 100038 China

A numerical study of sea waves generated by tropical cyclone Jelawat is carried out using the cycle 4 version of the *** model domain currently covers the latitudes 2.-45 N and longitudes 115-135 E,and the model spatial resolution reaches 0.2. ×*** of the model results with buoy observations reveals that the model can fairly reproduce the temporal variation of observed ***-dimensional comparison is also made against the satellite altimeter significant wave heights derived from TOPEX/POSEIDON and ERS-2.data,showing high quality of the model performance.

关键词： wave model tropical cyclone Jelawat simulation altimeter wave height

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Three-dimensional calculations of the currents in the Huanghai Sea and East china Sea during June of 1999

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Acta Oceanologica Sinica 2003年第3期22卷 333-349页

作者： Huiqun Wang, Yaochu Yuan, Yonggang Liu, Mingyu Zhou Second Institute of Oceanography, State Oceanic administration, Hangzhou 310012. china. E-mail: wanghq@sio. zj. edu.cnKey {2. of Ocean Dynamic Processes and Satellite Oceanography of State Oceanic administration, Hangzhou 310012. chinaNational Center for Marine Environmental Forecasts, beijing 100081, china Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China Key Lab. of Ocean Dynamic Processes Hangzhou 310012 China Natl. Ctr. Mar. Environ. Forecasts Beijing 100081 China

Based on the wind and hydrographic data obtained by R/V Xiangyanghong 14 during June of 1999, the currents in the Huanghai Sea and East china Sea are computed by the three dimensional non-linear diagnostic, semidiagnostic models and prognostic in the a coordinate. The computed results show that the density and velocity fields and so on have been adjusted when time is about 3 days, namely the solution of semidiagnostic calculation is obtained. In the northwest part of the computed region, the Huanghai coastal current flows southeastward, and then it flows out the computed region south of Cheju Island. In the west side of the southern part of the computed region, there is other current, which is mainly inshore branch of Taiwan Warm Current, and it flows cyclonically and turns to the northeast. In the region north of the above two currents, there is a cyclonic eddy southwest of Cheju Island, and it has characteristics of high density and low temperature. There is an offshore branch of Taiwan Warm Current in the west side of the Kuroshio, and it makes a cyclonic meander, then flows northeastward. The Kuroshio in the East china Sea is stronger, and flows northeastward. Its maximum horizontal velocity is 108.5 cm/s at the sea surface, which is located at the northern boundary, and it is 106.1 cm/s at 30 m level, 102.2.cm/s at 75 m level and 85.1 cm/s at 2.0 m level, respectively, which are all located at the southern boundary. Comparing the results of diagnostic calculation with those of semidiagnostic and prognostic calculations indicates that the horizontal velocity field agrees qualitatively, and there is a little difference between them in quantity. The comparison between the computed velocities and the observed velocities at the mooring station show that they agree each other.

关键词： non-linear diagnostic and semidiagnostic and prognostic models currents in the East china and Huanghai Seas

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Photosynthetically active radiation retrieval based on HJ-1A/B satellite data

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Science china Earth Sciences 2010年第S1期53卷 81-91页

作者： LI Li1,XIN XiaoZhou1,SU GaoLi1,2.& LIU QinHuo1 1 State Key laboratory of Remote Sensing Science,Institute of Remote Sensing Applications,Chinese Academy of Sciences,beijing 100101,{2. 2.Zhejiang climate Center,Hangzhou 310017,{2. State Key laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China Zhejiang climate Center Hangzhou China

Photosynthetically active radiation(PAR) is essential for plant photosynthesis and carbon cycle,and is also important for meteorological and environmental *** advance china's disaster and environmental monitoring capabilities,the HJ-1A/B satellites have been placed in Earth *** of their environmental monitoring objectives is the study of *** simulated direct solar,scattered and environment radiation between 400 and 700 nm under different atmospheric parameters(solar zenith angle,atmospheric water vapor,atmospheric ozone,aerosol optical thickness,surface elevation and surface albedo),and then established a look-up table between these input parameters and *** on the look-up table,we used HJ-1A/B aerosol and surface albedo outputs to derive the corresponding *** of inversed instantaneous and observed PAR values using HJ-1 Heihe experimental data had a root mean square error of 2..2.W m-2.with a relative error of 5.9%.The root mean square error for accumulated daily PAR and observed values was 0.49 MJ m-2.with a relative error of 3.5%.Our approach improved significantly the computational efficiency,compared with using directly radiation transfer *** also studied the sensitivity of various input parameters to photosynthetically active radiation,and found that solar zenith angle and atmospheric aerosols were sensitive PAR *** albedo had some effect on PAR,but water vapor and ozone had minimal impact on PAR.

关键词： Photosynthetically active radiation 6S HJ-1A/B satellites

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Spatial patterns of ecosystem carbon residence time in Chinese forests

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中国科学：地球科学英文版 2010年第8期53卷 1229-1240页

作者： ZHOU Tao1,2. SHI PeiJun1,2. JIA GenSuo3, LI XiuJuan1,2.& LUO YiQi4 1 State Key laboratory of Earth Surface Processes and Resource Ecology, beijing Normal University, beijing 100875, china 2.Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs & Ministry of Education, beijing 100875, china 3 Key laboratory of Regional climate-Environment Research for Temperate East Asia, Chinese Academy of Sciences, beijing 10002., china 4 Department of Botany and Microbiology, University of Oklahoma, Norman, OK 73019, USA State Key laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing China Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs & Ministry of Education Beijing China Key laboratory of Regional climate-Environment Research for Temperate East Asia Chinese Academy of Sciences Beijing China Department of Botany and Microbiology University of Oklahoma Norman USA

Capacity of carbon sequestration in forest ecosystem largely depends on the trend of net primary production (NPP) and the length of ecosystem carbon residence time. Retrieving spatial patterns of ecosystem carbon residence time is important and necessary for accurately predicting regional carbon cycles in the future. In this study, a data-model fusion method that combined a process-based regional carbon model (TECO-R) with various ground-based ecosystem observations (NPP, biomass, and soil organic carbon) and auxiliary data sets (NDVI, meteorological data, and maps of vegetation and soil texture) was applied to estimate spatial patterns of ecosystem carbon residence time in Chinese forests at steady state. In the data-model fusion, the genetic algorithm was used to estimate the optimal model parameters related with the ecosystem carbon residence time by minimizing total deviation between modeled and observed values. The results indicated that data-model fusion technology could effectively retrieve model parameters and simulate carbon cycling processes for Chinese forest ecosystems. The estimated carbon residence times were highly heterogenous over china, with most of regions having values between 2. and 70 years. The deciduous needleleaf forest and the evergreen needleleaf forest had the highest averaged carbon residence times (73.8 and 71.3 years, respectively), the mixed forest and the deciduous broadleaf forest had moderate values (38.1 and 37.3 years, respectively), and the evergreen broadleaf forest had the lowest value (31.7 years). The averaged carbon residence time of forest ecosystems in china was 57.8 years.

关键词： carbon residence time carbon cycle forest ecosystem data-model fusion inverse modeling genetic algorithm

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A New Approach to the On-Orbit Evaluation of Point Spread Function of Thermal Infrared Images With Applications to FY-2.Satellite Products

A New Approach to the On-Orbit Evaluation of Point Spread Fu...

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作者： Qiang Guo,Changjun Yang,and Caiying Wei the National Satellite meteorological Center,china meteorological administration,beijing 100081,china,the Key laboratory of Radiometric Calibration and Validation for Environmental Satellite,china meteorological administration,beijing 100081,china

Spatial characteristics of thermal infrared(TIR) images are generally described by image-derived point spread function(IDPSF) for sampled imaging *** investigators working on IDPSF on-orbit evaluation focus on visible and near-infrared images and pay little attention on TIR ones,the reason of which lies on the fact that the assumption of an observed target with an ideal step profile is not suitable for TIR band. A new approach for TIR images is proposed here based on a more common slope-profile model,where the transition features, i.e.,the sample number(N) and the beginning position of slope interval,are extracted from the observed *** results show that the estimation performance will be increased, with lower noise level as well as higher system modulation transfer function value at half of normalized spatial frequency(MTF) or smaller *** a good performance system with noise squared-root variance(SRV) no more than 1.0 count and MTF between 0.3 and 0.4,the relative error between simulated and estimated MTF\s is less than 2.%.The IDPSF of FY-2. satellite TIR band is estimated,and the derived MTF0.5 is properly close to on-ground testing *** image quality of FY-2. TIR band has been improved by using Wiener filtering and the estimated IDPSF,which eventually benefits the cloud detection product with more detectable low fractus and increased detection accuracy by about 1%in *** a step-profile target as a special case of this model,the proposed approach is also suitable for visible and near-infrared images.

关键词： Index Terms—Infrared imaging optical image processing optical transfer functions.

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Pollution characteristics of atmospheric fine particles and their secondary components in the atmosphere of Shenzhen in summer and in winter

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Science china Chemistry 2006年第5期49卷 466-474页

作者： NIU Yuwen1,2.HE Lingyan1,2.HU Min2.ZHANG Jing2.& ZHAO Yunliang2.1. Shenzhen Graduate School of Peking University,Shenzhen 518055,china 2. State Joint Key laboratory of Environmental Simulation and Pollution Control,College of Environmental Sciences,Peking University,{2. 100871,china Shenzhen Graduate School of Peking University Shenzhen China State Joint Key laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing China

Two field measurements for atmospheric fine particles were conducted in Baoan district of Shenzhen during the summer and winter in 2.04. Totally 30 sets of 2. h samples were collected, and then the mass concentrations and chemical compositions were determined. The seasonal varia- tions and secondary pollution characteristics of fine particles during the sampling periods were dis-cussed with meteorological factors. The results show that seasonal variations of atmospheric particles are significant in Shenzhen. The average mass concentrations of PM2.5 and PM10 in summer were 35 μg·m-3 and 57 μg·m-3, respectively, and those in winter were 99 μg·m-3 and 135 μg·m-3, respec-tively. The concentrations of both PM2.5 and PM10 in winter increased 184% and 137%, respectively, compared to those in summer. PM2.5 accounted for 61% and 75% of PM10 in summer and in winter, respectively, indicating severe fine particle pollution in Shenzhen. During the summer and winter sampling periods, the mean OC/EC ratios were 3.4 and 1.6, respectively. The estimated secondary organic carbon (SOC) averagely accounted for 56% and 6% of the total OC in summer and in winter, respectively, which implies a major contribution of SOC to OC in summer. During the continuous high temperature period in summer, both the concentrations and fractions of secondary aerosol compo-nents in PM2.5 were highly elevated, suggesting severe secondary pollution again. The prevailing wind was from South china Sea in summer, and the air quality was good. The prevailing wind in winter was from china's Mainland to the north, and the polluted air mass led to poor air quality.

关键词： PM2.5, mass concentration, secondary pollution, seasonal variation, Shenzhen.

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

Simulation of 1991-2005 Meiyu seasons in the Yangtze-Huaihe ...

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第七届全国优秀青年气象科技工作者学术研讨会

作者： HU YaMin1,2.DING YiHui3 1 Guangdong climate Center, Guangzhou 510080, china 2.Institute of Tropical and Marine Meteorology,{2., Guangzhou 510080, china 3 National climate Center,{2., beijing 100081, china

By using BCCegCM 1.0 (RegCM for short) from beijing climate Center (BCC),{2. (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 15a, 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.day, 3 days 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： regional climate model Meiyu in Yangtze-Huaihe region Meiyu onset Meiyu ending Meiyu rainfall

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