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Variations of δ^(18)O in precipitation from the Muztagata Glacier, East Pamirs

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Science china Earth Sciences 2006年第1期49卷 36-42页

作者： LI Zhen1, YAO Tandong1,2. TIAN Lide1,2. XU Baiqing1,2.& Wu Guangjian2.1. Key laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering Research Institute and Institute of Tibetan Plateau Research, Chinese Academy of Sciences and Chinese Academy of meteorological Sciences,{2., CAS, Lanzhou 73.000, china 2. laboratory of Environment and Process on Tibetan Plateau, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085, china 1. Key laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China 2. laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

Expeditions to Muztagata (in the eastern Pamirs) during the summer seasons of2.02.and 2.03.collected precipitation samples and measured their oxygen isotopes. The δ^(18)O inprecipitation displays a wide range, varying from -17.40per thousand to +1.3.per thousand inJune—September 2.02.and from -2..3.per thousand to +4.59per thousand in May—August 2.03. Theδ^(18)O in precipitation correlates with the initial temperature of precipitation during theobserving periods. The positive correlation between δ^(18)O and temperature suggests that δ^(18)Ocan be used as an indicator of temperature in this region. The δ^(18)O values in fresh-snow samplescollected from two snow events at different elevations on the Muztagata Glacier show a strong''altitude effect'', with a ratio of nearly -0.40per thousand per 100 m from 5500 m to 7450 m.

关键词： Muztagata, δ18O, temperature, altitude effect.

Evolution of desertification in a two-dimensional energy balance model coupled with thermodynamics and dynamics

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Science china Earth Sciences 2010年第11期53卷 1726-1733页

作者： CHAO JiPing1,2.& LI YaoKun3.4 1National Marine Environmental Forecasting Center, beijing 100081, china 2.irst Institute of Oceanography, State Oceanic {2., Qingdao 2.6061, china 3.tate Key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., china 4Graduate University of Chinese Academy of Sciences, beijing 100049, china 1. National Marine Environmental Forecasting Center Beijing 100081 China2. First Institute of Oceanography State Oceanic Administration Qingdao 266061 China3. State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China4. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The relationship between desert evolution and change in albedo has been investigated quasi-analytically using a zonal mean two-dimensional energy balance model which considers the radiation transmission process due to thermodynamics and bound- ary layer movement caused by kinetics. A climate state including temperature, zonal wind, meridional wind and vertical wind can be simulated according to the current zonal distribution of albedo. Given desert distribution, characterized by the value and distribution of albedo, the response of climate on albedo has been studied to analyze the evolution of desert climate. One significant result is that the simple model can reproduce mean meridional circulation. Another result indicates that climate corresponds to two equilibria. This happens when the junction temperature between vegetation and desert is higher than a certain critical value. As for the first equilibrium, the desert belt is predicted to move southward in the northern hemisphere with the increasing values of albedo, which corresponds to the current trend of climate change. For the second equilibrium, vegetation will expand northward with increasing values of albedo, which would indicate a narrowing of the desert belt. In order to determine if the two equilibria exist, new physical models are needed.

关键词： two-dimensional energy balance model desertification two equilibria

Sporopollen analysis of Core B10 in the southern Yellow Sea and the reflected characteristics of climate changes

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Chinese Science Bulletin 2003年第B06期48卷 42-48页

作者： FU Mingzuo~(1,2.3., LI Zhen~1, XU Xiaowei~1 & SHl Xuefa~1 1. Key laboratory of Marine Sedimentology and Environmental Geology, First institute of Oceanography. State Oceanic administration, Qingdao 2.6061.{2. 2. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 2.6071.{2. 3. Graduate School, Chinese Academy of Sciences, beijing 10003..{2. 1. Key laboratory of Marine Sedimentology and Environmental Geology First institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. Institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. Graduate School Chinese Academy of Sciences 100039 Beijing China

Eight sporopollen zones have been divided based on the results of high-resolution sporopollen analysis of Core B10 in the southern Yellow Sea. Based on the results along with ^14C datings and the subbottom profiling data,climatic and environmental changes since the last stage of late Pleistocene are discussed. The main conclusions are drawn as follows: (1) the vegetation evolved in the process of coniferous forest-grassland containing broad-leaved trees→coniferous and broad-leaved mixed forest→coniferons and broad-leaved mixed forest-grassland prevailed by coniferous trees→coniferous and broad-leaved mixed forest-grassland containing evergreen broad-leaved trees→coniferons and broad-leaved mixed forest-grassland prevailed by broadleaved trees→deciduous broad-leaved forest-meadow containing evergreen broad-leaved trees→coniferous and broadleaved mixed forest-grassland prevailed by broad-leaved trees→coniferous and broad-leaved mixed forest containing evergreen broad-leaved trees; (2. eight stages of climate changes are identified as the cold and dry stage, the temperate and wet stage, the cold and dry stage, the warm and dry stage, the temperate and wet stage, the hot and dry stage, the temperate and dry stage, then the warm and dry stage in turn; (3. the sedimentary environment developed from land,to littoral zone, to land again, then to shore-neritic zone; and (4) the Yellow Sea Warm Current formed during early-Holocene rather than Atlantic stage.

关键词：中国黄海气候变化碳14年代测定底基压型数据更新世沉积环境大西洋

Influence of atmospheric heat sources over the Tibetan Plateau and the tropical western North Pacific on the inter-decadal variations of the stratosphere-troposphere exchange of water vapor

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Science china Earth Sciences 2008年第8期51卷 1179-1193页

作者： ZHAN RuiFen1,2.LI JianPing2.1Shanghai Typhoon Institute of china meteorological administration,Shanghai 2.003.,china 2.tate Key {2. of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG),Institute of Atmospheric Physics,Chinese Academy of Sciences,beijing 10002.,china 1. Shanghai Typhoon Institute of china meteorological administration Shanghai 200030 China 2. State Key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

This study investigates the Stratosphere-Troposphere Exchange(STE) of water vapor,emphasizes its interdecadal variations over Asia in boreal summer,and discusses the influences of atmospheric heat sources over the Tibetan Plateau and the tropical western North Pacific(WNP) on them by using the Wei method with reanalysis data from the European Centre for Medium-Range Weather Forecasts(ECMWF) for the years of *** climatology shows that the upward transport of water vapor across the tropopause in boreal summer is the most robust over the joining area of the South Asian Peninsula and Indian-Pacific Oceans(defined as AIPO).The upward transport over there can persistently convey the abundant water vapor into the stratosphere and then influence the distribution and variation of the stratospheric water *** analysis shows that interdecadal variations of the water vapor exchange over the AIPO are significant,and its abrupt change occurred in the mid-1970s and the early *** these three periods,as important channels of the water vapor exchange,the effect of Bay of Bengal-East Asia as well as South china Sea was gradually weakening,while the role of the WNP becomes more and more *** studies show that atmospheric heat sources over the Tibetan Plateau and the WNP are two main factors in determining the interdecadal variations of water vapor *** thermal influences over the Tibetan Plateau and the WNP have been greatly adjusted over the pass 44 *** synthesis influences the interdecadal variations of the water vapor exchange by changing the Asian summer monsoon,but their roles vary with time and *** after 1992.the influence of heat source over the Tibetan Plateau remarkably weakens,while the heat source over the WNP dominates the across-tropopause water vapor *** have important implications for understanding the transport of other components in the atmosphere and estimating the impact of human activities(

关键词： Tibetan Plateau tropical western North Pacific atmospheric heat source STE inter-decadal variations

Changes in the spatial scale of beijing UHI and urban development

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Science china Earth Sciences 2005年第Z2期48卷 116-127页

作者： YU Shuqiu, BIAN Lingen & LIN Xuechun State Key laboratory on Severe Weather, Chinese Academy of meteorological Sciences,{2.,{3. National climate Center, china meteorological administration,{2.,{3. State Key laboratory on Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China National climate Center China Meteorological Administration Beijing 100081 China

The seasonal and interannual variations of beijing urban heat island (UHI) are investigated in this paper using the temperature data from 1960 to 2.00 at 2. {3. stations in the beijing region, and then the relationship between the intensity and spatial scale of UHI and beijing urbanization indices is analyzed and discussed. Main conclusions are the followings. First, beijing UHI shows obvious seasonal variations, and it is strongest in winter, next in spring and autumn, and least in summer. The seasonal variation of the UHI mainly occurs in the urban area. The UHI intensity at the center of beijing is more than 0.8℃ in winter, and only 0.5℃ in summer. Second, the intensity of beijing HUI exhibits a clear interannual warming trend with its mean growth rate (MGR) being 0.3.88℃/10 a. The MGR of HUI is largest in winter, next in spring and autumn, and least in summer, and the urban temperature increase makes a major contribution to the growth of HUI intensity. Third, since the Reform and Opening, the urbanization indices have grown several ten times or even one hundred times, the intensity of HUI has increased dramatically, and its spatial scale also expanded distinctively along with the expansion of urban architectural complexes. Fourth, the interannual variation of urbanization indices is very similar with that of HUI intensity, and their linear correlation coefficients are significant at a more than 0.001 confidence level.

关键词： beijing region, temperature change, heat island effect, HUI spatial scale, human activities.

Variations of near-surface atmospheric CO_(2.and H_(2.O concentrations during summer on Muztagata

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Science china Earth Sciences 2006年第1期49卷 18-26页

作者： XU Baiqing1,2. YAO Tandong1,2. LU Anxin2. GUO Xuejun, LIU Xianqin2.& LI Zhen2.1. laboratory of Environment and Process on Tibetan Plateau, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085,{2. 2. Key laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering Research Institute and Institute of Tibetan Plateau Research, Chinese Academy of Sciences and Chinese Academy of meteorological Sciences, china meteorological administration, Lanzhou 73.000,{2. 1. laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Key laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China

Expeditions during the summers of 2.02.and 2.03.implemented continuous monitoring of near-surface (2.m height) atmospheric CO2.and H2. concentrations at the 4500 m elevation on Muztagata. The resultant data sets reveal a slight decrease of CO2.concentrations (of about 5 μmol·mol?1) and changes in the diurnal variations from the end of June to the middle August. The daily maximum CO2.concentrations occur between 02.3.―05:3. AM (local time) and the minimum levels occur between 12.00―15:3. PM. The atmospheric CO2.concentrations in the summer of 2.02.were around 5 μmol·mol?1 lower than those during the same period of 2.03. whereas the diurnal amplitude was higher. In contrast, we found that the daily mean atmospheric H2. content in 2.03.was much lower than that in 2.02.and there exists a striking negative correlation between CO2.and H2. con-centrations. We therefore suggest that the near-surface atmospheric CO2.concentration is affected not only by photosynthesis and respiration, but also by the air H2. content in the glaciated region around Muztagata.

关键词： atmospheric CO2 and H2. concentration, continuous monitoring, glaciation region, Muztagata.

Distribution characteristics of magnetic susceptibility of the surface sediments in the southern Yellow Sea

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Chinese Science Bulletin 2003年第B06期48卷 37-41页

作者： GE Shulan~(1,2.3., SHI Xuefa~1 & HAN Yibing~1 1. Key laboratory of Marine Sedimentology and Environmental Geology, First Institute of Oceanography, State Oceanic administration. Qingdao 2.6061.{2. 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 10002..{2. 3. Graduate School. Chinese Academy of Sciences, beijing 10003..{2. 1. Key laboratory of Marine Sedimentology and Environmental Geology First Institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 3. Graduate School Chinese Academy of Sciences 100039 Beijing China

The characteristic distributions of magnetic susceptibility (MS) are analyzed on the basis of susceptibility of 172.surface sediment samples in the southern Yellow Sea (SYS). The preliminary results are as follows: first, the distributions clearly correspond to different modern sediment assemblages in the continental sea, which indicates different sediment origins. With the 3. μCGS isoline being taken as demarcation line, the study area can then be divided into section H (high MS value area) and section L (low MS value area). Section H is mainly adjacent to land with two main sources of the Changjiang River and the Huanghe *** L is mainly an eddy sediment area, where Yellow Sea Cold Water is entrenched all the year round. The distribution pattern of MS could tell apart strong or weak hydrodynamic conditions and has a close relation to the circulation system in this area. At the areas of the SYS Circumfluent and northern East china Sea (NECS) Circumfluent (weak hydrodynamic), the MS has low values, while in the areas of Coastal Current (strong hydrodynamic), the values are *** the same time, the oxidizing areas tend to take on higher MS, while the reducing areas have lower one. It seems safe to say that the MS in the continental sea reflects more of the sediment origin and sedimentary environment, which is different from that of loess, lake and surface soil as a climate proxy.

关键词：中国黄海表面沉积物磁化率等值线长江黄河旋涡沉积区循环系统

The characteristics of atmospheric CO_2.concentration variation of four national background stations in china

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Science china Earth Sciences 2009年第11期52卷 1857-1863页

作者： LIU LiXin, ZHOU LingXi, ZHANG XiaoChun, WEN Min, ZHANG Fang, YAO Bo & FANG ShuangXi Key laboratory for Atmospheric Chemistry, Centre for Atmosphere Watch and Services (CAWAS), Chinese Academy of Meteoro- logical Sciences (CAMS), china meteorological administration (CMA),{2.,{3. Key laboratory for Atmospheric Chemistry Centre for Atmosphere Watch and Services (CAWAS) Chinese Academy of Meteorological Sciences (CAMS) China Meteorological Administration (CMA) Beijing 100081 China

Atmospheric carbon dioxide is an important kind of greenhouse gas which influences global temperature. Its concentration variation could indicate the distribution of human and natural activities in various regions. Through the non-dispersive infrared method, flask sampling of atmospheric CO2.concen- tration was measured weekly at four national background stations including Waliguan, Shangdianzi, Lin’an, and Longfengshan. Based on the data collected from September 2.06 to August 2.07, along with the Waliguan station’s experience on in situ observational data processing, the selection methods for sampling data through the atmospheric background CO2.concentration analysis were preliminarily discussed. On the basis of this result, the variation features of the four typical regions’ atmospheric background CO2.concentration was analyzed for the first time. The results show that the atmospheric CO2.concentration at Waliguan, Shangdianzi, Lin’an, and Longfengshan is 3.3.5, 3.5.9, 3.7.8, and 3.4.3.ppm, respectively. During the research period, CO2.concentration at the Waliguan station changed slightly. However, the CO2.concentration changed sharply at the Shangdianzi and the Lin’an stations due to the great influence of human activities in the Jingjinji and the Changjiang Delta economic zones, and changed regularly with seasons at Longfengshan station under dual influences of human activities and plant photosynthesis. The results from this study can lay the foundation for more profound studies on atmospheric CO2.concentration level of different areas in china, and could be used to improve the understanding of carbon source and sink distribution.

关键词： atmospheric CO2 flask sampling background data selection CO2 concentration regional difference

Relationships between δ ^(18)O in summer precipitation and temperature and moisture trajectories at Muztagata, western china

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Science china Earth Sciences 2006年第1期49卷 27-35页

作者： YU Wusheng1,2. YAO Tandong1,2. TIAN Lide1,2. LI Zhen2. SUN Weizhen2.& WANG Yu2.1. laboratory of Environment and Process on Tibetan Plateau, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085,{2. 2. Key laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering Research Institute and Institute of Tibetan Plateau Research, Chinese Academy of Sciences and Chinese Academy of meteorological Sciences, china meteorological administration, CAS, Lanzhou 73.000,{2. 1. laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Key laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China

Based on summer observations of stable isotope of precipitation at Muztagata, western china, during 2.02.2.03. this paper presents the relationship between δ 18O in precipitation and air temperature, and discusses the effect of moisture transport on δ 18O in precipitation. Results show that air temperature correlates positively with δ 18O in precipitation, and the temperature effect controls the δ 18O of precipitation in this area. The Muztagata region exhibits high δ 18O values in summer precipi-tation, similar to those shown at stations in adjacent regions. According to the results of our model set up to trace the moisture trajectories, the westerlies and local moisture circulation contribute to varia-tions of oxygen isotopes in precipitation. In addition, the impacts of the moisture transport distance, the moisture transport level, and the incursion of the polar air mass also influence the variations of δ 18O in precipitation. The moisture origins and transport mechanisms also contribute to the variation of δ 18O in precipitation at Muztagata.

关键词： Muztagata, δ18O, precipitation, temperature, moisture transport.