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A primary study of the correlation between the net air-sea heat flux and the interannual variation of western North Pacific tropical cyclone track and intensity

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Acta oceanologica Sinica 2011年第6期30卷 27-35页

作者： WU Liang WEN Zhiping HUANG Ronghui center for Monsoon and environment research/department of Atmospheric sciences Sun Yat-sen University Guangzhou 510275 China center for Monsoon System research Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

A singular value decomposition （SVD） analysis is carried out to reveal the relationship between the interannual variation of track and intensity of the western North Pacific tropical cyclones （WNPTCs） in the tropical cyclone （TC） active season （July–November） and the global net air-sea heat flux （Q net ） in the preceding season （April–June）. For this purpose, a tropical cyclone track and intensity function （TIF） is defined by a combination of accumulated cyclone energy （ACE） index and a cyclone track density function. The SVD analysis reveals that the first mode is responsible for the positive correlation between the upward heat flux in the tropical central Pacific and the increased activity of western North Pacific （WNP） TIF, the second mode for the positive correlation between the upward heat flux in the North Indian ocean and the northeastward track shift of WNPTCs and the third mode for the negative correlation between the upward heat flux in mid-latitude central Pacific and the northwest displacement of the WNP TC-active center. This suggests that Q net anomalies in some key regions have a substantial remote impact on the WNP TC activity.

关键词： tropical cyclone western North Pacific the net air-sea heat flux (Q net ) interannual variation

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china earth sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2,3 & WANG Huijun2 1. Nansen-Zhu International research center, Institute of Atmospheric Physics, Chinese Academy of sciences, Beijing 100029, china 2. department of Atmospheric Science, Yunnan university, Kunming 650091, china 3. Graduate university of the Chinese Academy of sciences, Beijing 100049, china Nansen-Zhu International research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China department of Atmospheric Science Yunnan University Kunming China Graduate university of the Chinese Academy of sciences Beijing China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Carbon and sulfur isotopic compositions of basal Datangpo Formation, northeastern Guizhou, South china:Implications for depositional environment

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Progress in Natural Science:Materials International 2008年第4期18卷 421-429页

作者： Xi Chen, Da Li, Hong-Fei Ling , Shao-Yong Jiang State Key Laboratory for Mineral Deposit research, department of earth sciences, Nanjing university, Nanjing 210093, china State Key Laboratory for Mineral Deposit research Department of Earth Sciences Nanjing University Nanjing 210093 China

Isotopic compositions of Mn-carbonate and organic carbon from the same individual samples and sulfur isotopic compositions of pyrites in the basal Datangpo Formation were analyzed. Highly 34S-enriched pyrites (d34Spyrite=31.7-59.4‰) were precipitated in rel- atively occlusive pore water under anoxic condition in sediments, which is consistent with the observation of large and scattered pyrite framboids. The sulfidic deep ocean was not "oxidized" in the early Datangpo interglacial interval, thus the level of seawater sulfate remained low and marine d34Ssulphate remained high. Low d13Ccar (average 7.4‰) and abnormal relationship between d13Ccar and frac-tionation (Dcar-org) imply that the negative d13Ccar excursion may have resulted from oxidation of part of a large organic carbon reser-voir. High Dcar-org (average 25.1‰) implicates high CO2 level in the atmosphere. Small standard deviation (1.0‰) of d13Ccar values indicates the Mn-carbonate was precipitated near the water-sediment interface under dysoxic conditions rather than in occlusive pore water in sediments.

关键词： Cisotope S isotope Paleoenvironment Datangpo Mn-carbonate

Helium isotope investigation on magnetic reversal boundaries of loess-paleosol sequence at Luochuan, central Chinese Loess Plateau

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Chinese Science Bulletin 2007年第17期52卷 2407-2412页

作者： DU XueQing1,6, WANG YongHong2, REN JianGuo3, YE XianRen4 & LU HuaYu5,1 1 State Key Laboratory of Loess and Quaternary Geology, Institute of earth environment, Chinese Academy of sciences, Xi’an 710075, china 2 College of Marine Geosciences, ocean university of china, Qingdao 266003, china 3 National Natural Science Foundation of china, Beijing 100085, china 4 Lanzhou research center for Petroleum and Natural Gas Resources, Institute of Geology and Geophysics, Chinese Academy of sciences, Lanzhou 730000, china 5 Key Laboratory of Coast and Island Development, School of Geographic and oceanographic sciences, Nanjing university, Nanjing 210093, china 6 Graduate university of Chinese Academy of sciences, Beijing 100049, china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi''an 710075 China Graduate university of Chinese Academy of sciences Beijing 100049 China College of Marine Geosciences Ocean University of China Qingdao 266003 China National Natural Science Foundation of china Beijing 100085 China Lanzhou research center for Petroleum and Natural Gas Resources Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China Key Laboratory of Coast and Island Development School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China

Extraterrestrial particles have higher 3He/4He ratios than those of terrestrial sediments ( > 100 Ra versus < 0.03 Ra, where Ra is the 3He/4He ratio normalized to the atmospheric value of 1.4×10?6). The inter- planet... 详细信息

Extraterrestrial particles have higher 3He/4He ratios than those of terrestrial sediments ( > 100 Ra versus earth and can accumulate in deposits. IDPs sedimentation rate changes can significantly influence 3He concentration in the earth surface sediments. Since IDPs are not easy to detect in terrestrial deposits, measuring helium isotopes is a helpful approach to examine changes in IDPs. Helium concentration and helium isotopic composition magnetic substances and the quartz particles were examined for helium concen- tration and helium isotopic ratio. Results show that the 3He/4He ratio and the 3He concentrations of the magnetic substances are clearly higher than those of the bulk samples and the quartz particles, and, the 3He/4He ratio of the extracted magnetic substances is also higher than that of the average level of the earth’s crust. The higher helium content in the magnetic fractions can be explained by an influx of IDPs.

关键词：中国黄土高原古土壤氦同位素行星际尘埃颗粒反方向磁化

Potential land for plantation of Jatropha curcas as feedstocks for biodiesel in china

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Science china earth sciences 2010年第1期53卷 120-127页

作者： WU WeiGuang 1,2,3,HUANG JiKun 1,3 & DENG XiangZheng 1,3 1 Institute of Geographic sciences and Natural Resources research,Chinese Academy of sciences,Beijing 100101,china 2 department of Economics and Management,Zhejiang Forestry university,Linan 311300,china 3 center for Chinese Agricultural Policy,Chinese Academy of sciences,Beijing 100101,china Institute of Geographic sciences and Natural Resources research Chinese Academy of Sciences Beijing China department of Economics and Management Zhejiang Forestry University Linan China center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing China

As a renewable energy,biofuel has attracted great attention in china and the rest of *** with the national food security,china recently has shifted its biofuel development priority from grain-based to non-grain-based biofuels,including forest-based biodiesel,since *** curcas is one of major biodiesel ***,there is rising debate on availability of land for expanding Jatropha curcas *** overall goal of this paper is to evaluate potential land for Jatropha curcas used as feedstock for biodiesel in *** on remote sensing data on land use,data on meteorological,soil and land slope,and suitable environment for Jatropha curcas plantation,this study uses Agro Ecological Zone method and considers social-economic constraints to evaluate potential suitable land for Jatropha curcas plantation in china's major Jatropha curcas production region,Southwest *** results show that while there are some potential lands to expand Jatropha curcas areas,amount of these lands will hardly meet the government's target for Jatropha curcas-based biodiesels development in the *** may need to reconsider its long-term targets on the development of Jatropha curcas-based biodiesels.

关键词： biodiesel Jatropha curcas potential land suitability evaluation Southwest china

Isotopic compositions of small shelly fossil Anabarites from Lower Cambrian in Yangtze Platform of South china: Implications for palaeocean temperature

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Progress in Natural Science:Materials International 2007年第10期17卷 1185-1191页

作者： Chen Yongquan1,2, Jiang Shaoyong1, Ling Hongfei1, Yang Jinghong1 and Wan Defan3(1. State Key Laboatory for Mineral Deposits research and center for Marine Geochemistry research, department of earth sciences, Nanjing university, Nanjing 210093, china 2. Tarim Oilfield Company Exploration & Development research Institute, Ku’erle 841000, china 3. Institute of Mineral Resources, Chinese Academy of Geological sciences, Beijing 100037, china) State Key Laboratory for Mineral Deposits research and center for Marine Geochemistry research Department of Earth Sciences Nanjing University Nanjing 210093 China Tarim Oilfield Company Exploration & Development research Institute Ku'' erle 841000 China Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

Anabarites belong to small shelly fossils (SSF), which occur widely in the Lower Cambrian strata of Yangtze Platform in South china. They are phosphate shell in composition and represent the earliest stage of the Cambrian bioradiation of Bilateria, the so-called "Cambrian Explosion". In this study, we attempted to separate Anabarites fossils from Lower Cambrian dolostones, and we obtained samples of both the fossils (SSF) and the granular phosphates (GP). Isotopic analyses were performed on samples of SSF, GP, and matrix dolostone (DH-23). The results showed that the δ30Si values of the quartz filling in fossils celoms, and the siliceous materials in granular phosphates are -0.6‰ and -0.7‰, which is different from normal sedimentary siliceous rocks from the Lower Cambrian strata (0—0.7‰) as reported by Li et al., but is consistent with the data for siliceous rocks and cherts of submarine hydrothermal origin. It is likely that a later hydrothermal replacement could have taken place in the SSF-bearing sedimentary rocks. The oxygen isotope values of the phosphate of SSF and GP are 16.8‰ and 17.0‰, respectively. These are significantly higher than the Neoproterozoic phosphate ores (10.9‰—13.9‰) as reported by Ling et al., hence, late diagenesis and hydrothermal replacement may not have caused a significant change in the oxygen isotope compositions of the small shelly fossils, and the calculated temperatures (25.4—26.3℃) for palaeo-seawater using a SSF phosphate oxygen isotope thermometer are therefore considered here as the upper limit of seawater temperature in the Early Cambrian ocean of the Yangtze Platform.

关键词： Anabarites oxygen isotope silicon isotope paleo-temperature.

The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science china earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2, CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic sciences and Natural Resources Re-search, Chinese Academy of sciences, Beijing 100101, china 2. Institute of Forestry, Chinese Academy of Forestry sciences, Beijing 100091, china 3. department of Civil Engineering, university of Hong Kong, Hong Kong, china 4. Eco-environmental research center, Chinese Academy of sciences, Beijing 100085, china 5. College of Resources and environment, Southwest Agricultural university, Chongqing 400716, china Correspondence should be addressed to Chen Hao Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Institute of Forestry Chinese Academy of Forestry Sciences Beijing China department of Civil Engineering University of Hong Kong Hong Kong China Eco-environmental research center Chinese Academy of Sciences Beijing China College of Resources and environment Southwest Agricultural University Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2, it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

Transition from platemargin to intraplate environment: Geochemistry of basalts in Paleogene Liaohe basin, northeastern china

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Science china earth sciences 2005年第12期48卷 2069-2080页

作者： WU Changzhi1, GU Lianxing1, REN Zuowei1,2, ZHANG Zunzhong1, CHEN Zhenyan2 & ZHAO Ming1 1. State Key Laboratory of Mineral Deposit research (Nanjing university), department of earth sciences, Nanjing university, Nanjing 210093, china 2. Exploration and Development research Institute of Liaohe Oilfield Branch Company, Petrochina, Panjin 124010, china State Key Laboratory of Mineral Deposit research (Nanjing university) Department of Earth Sciences Nanjing University Nanjing China Exploration and Development research Institute of Liaohe Oilfield Branch Company PetroChina Panjin China

Paleogene basalts from the Liaohe basin, northeastern china, are dominated by alkaline olivine basalts and olivine basalts. These basalts are generally enriched in high field strength elements (HFSE), depleted in large ion lithophile elements (LILE) and comparable to those of typical ocean island basalts (OIB). Positive anomalies of Ba, Sr and Zr with high Nb/U, U/Pb, Ce/Pb and Zr/Hf ratios imply that materials from an oceanic crust had been added to the mantle sources of the basalts. In addition, the basalts are generally depleted in Sr, Nd and Pb isotopes, indicating that an enriched mantle (EMI) and a depleted mantle (DM) sources were added to the OIB-like resource. Comprehensive research on lithosphere evolution and tectonic setting of the Liaohe basin and surrounding areas suggests that these basalts were derived by variable degrees of partial melt-ing from an upwelling asthenosphere mantle. Materials from an oceanic lithosphere were added to the source in company with Paleogene tectonic transition from platemargin to intraplate envi-ronment. Retreating and steepening of the subducting Pacific oceanic plate could be the main cause for the tectonic environment transition.

关键词： geochemistry, basalt, Paleogene, Liaohe basin, North china Block, eastern china.

Modeling the impact of Australian Plate drift on Southern Hemisphere climate and environment

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Chinese Science Bulletin 2005年第14期50卷 1495-1502页

作者： ZHOU Botao1,5, ZHAO Ping2, JIAN Zhimin3 & HE Jinhai4 1. Nansen-Zhu International research center, Institute of Atmospheric Physics, Chinese Academy of sciences, Beijing 100029, china 2. Institute of Climate and environment, Chinese Academy of Meteoro- logical sciences, Beijing 100081, china 3. Laboratory of Marine Geology, Tongji university, Shanghai 200092, china 4. department of Atmospheric sciences, Nanjing Institute of Meteorol- ogy, Nanjing 210044, china 5. Graduate School of the Chinese Academy of sciences, Beijing 100039, china Nansen-Zhu International research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate School of the Chinese Academy of sciences Beijing 100039 China Institute of Climate and environment Chinese Academy of Meteorological Sciences Beijing 100081 China Laboratory of Marine Geology Tongji University Shanghai 200092 China department of Atmospheric sciences Nanjing Institute of Meteorology Nanjing 210044 China

Using a global atmosphere-ocean coupled model with the present-day and 14 MaB.P. oceanic topogra- phy respectively, two experiments are implemented to inves- tigate the effect of different locations of Australian Plate on the atmospheric circulation in middle-high latitudes of the Southern Hemisphere. The results show that when Austra- lian Plate lay south at 14 MaB.P., both anticyclone circula- tions in the subtropical oceans and cyclone circulation around 60°-70°S are strengthened. Subtropical highs and circumpolar low pressure appear stronger, which results in much stronger Antarctic Oscillation and shorter period of Antarctic Oscillation Index (AOI) at 14 MaB.P. The rainfall and the surface air temperature also change correspondingly. The precipitation decreases around 40°S and increases around 60°-70°S, and the surface air temperature rises in high latitudes of the South Pacific and descends over the Weddell Sea and its north side. Besides, due to the changes of the temperatures and winds, Antarctic sea ice coverage also changes with its increasing in the Ross Sea and its west re- gions and decreasing in the Weddell Sea.

关键词：半球气候地球环球澳大利亚漂流物海洋地形学