检索结果-南通市图书馆

Relationship and its instability of ENSO--chinese variations in droughts and wet spells

Science china Earth sciences 2007年第1期50卷 145-152页

作者： SU MingFeng1,2 & wang huijun1 1 Nansen-Zhu International Research Center, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china 2 Graduate University of chinese academy of sciences, beijing 100039, china 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Graduate University of chinese academy of sciences Beijing 100039 China

Monthly data of Self-Calibrated Palmer Drought Severity Index (PDSI) from 1951 to 2000 are calculated using historical precipitation and temperature data for chinese 160 stations. Temporal and spatial pat-terns of the first empirical orthogonal function (EOF) of the PDSI reveals a fairly linear trend resulting from trends in precipitation and surface temperature, which is similar to the linear PDSI trend during 1951―2000 calculated using all monthly data. The EOF analysis also reveals that the leading mode correlates significantly with ENSO events in time and space. The ENSO EOF shows that during the typical warm phase of ENSO, surface conditions are drier in most regions of china, especially North china, but wetter than normal in the southern regions of Changjiang River, and Northwest china. During the typical cold phase of ENSO, these anomalies reverse sign. From 1951 to 2000, there are large multi-year to decadal variations in droughts and wet spells over china, which are all closely related to strong El Nio events. In other words, when one strong El Nio event happens, there is a possible big variability in droughts and wet spells over china on the multi-year or decadal scale. Studies also sug-gest that during the last 2―3 decades climate changes over china, especially North china's drying and northwest china's wetting, are closely related to the shift in ENSO towards warmer events and global warming since the late 1970s. The instability of the relationship is also studied. It is revealed that there is a good correlation between ENSO and chinese variations in droughts and wet spells in the 3―8-year band, but the correlation between ENSO and chinese variations in droughts and wet spells is instable. Studies suggest that there are decadal changes in the correlation: the wavelet coherency between ENSO and chinese variations in droughts and wet spells is high during 1951―1962 and 1976―1991, but low during 1963―1975 and 1992―2000.

关键词： PDSI variations droughts and wet Spells ENSO instability.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of atmospheric aerosols on UV-B radiation reaching the ground

引用

Journal of Environmental sciences 1993年第2期5卷 224-229页

作者： wang Shaobin Su WeihanResearch Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china Research Center of Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China. China

Solar ultraviolet radiation reaching the ground can be reduced due to light scattering of atmospheric aerosols. Aerosol pollution has led to the decrease in biological active UV-B radiation by about 45% and 10% in city and rural areas, respectively. In populated areas, effect of aerosol scattering on UV-B radiation may offset the increased amount of UV-B caused by ozone depletion, but in clean areas such as two poles, ozone depletion may have great damage effects on ecosystems.

关键词： atmospheric aerosol UV-B radiation ozone reduction.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Biologically effective ultraviolet radiation in beijing area

引用

Journal of Environmental sciences 1993年第2期5卷 216-223页

作者： wang Shaobin Su WeihanResearch Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China. China

Ozone layer depletion implies the enhancement of solar ultraviolet radiation at the earth's surface. However, aerosol contributes to the scattering of solar radiation and leads to the reduction of UV-B radiation on the ground. In this paper, the model calculation shows that due to effects of atmospheric ozone and aerosol UV-B radiation in beijing in the past decade has decreased with the annual change rate of 0.7%, which is probably approximate to the measured values. The effects of three scenarios for long-term changes in atmospheric ozone and aerosol concentrations on UV-B radiation reaching the ground in are also discussed.

关键词： UV-B biological efftent zone aerosol beijing.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Soil respiration in tropical seasonal rain forest in Xishuangbanna, SW china

引用

Science china Earth sciences 2005年第Z1期48卷 189-197页

作者： SHA Liqing, ZHENG Zheng, TANG Jianwei, wang Yinghong, ZHANG Yiping, CAO Min, wang Rui, LIU Guangren, wang Yuesi & SUN Yang Xishuangbanna Tropical Botanical Garden, chinese academy of sciences, Kunming 650223, china institute of atmospheric physics, chinese academy of sciences, beijing 100029, china Graduate School of chinese academy of sciences, beijing 100039, china Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Kunming 650223 China Graduate School of chinese academy of sciences Beijing 100039 China Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Kunming 650223 China institute of atmospheric physics Chinese Academy of Sciences Beijing 100029 China

With the static opaque chamber and gas chromatography technique, from January 2003 to January 2004 soil respiration was investigated in a tropical seasonal rain forest in Xishuangbanna, SW china. In this study three treatments were applied, each with three replicates: A (bare soil), B (soil+litter), and C (soil+litter+seedling). The results showed that soil respiration varied seasonally, low from December 2003 to February 2004, and high from June to July 2004. The annual average values of CO2 efflux from soil respiration differed among the treatments at 1 % level, with the rank of C (14642 mgCO2 · m-2 · h-1)>B (12807 mgCO2 · m-2 · h-1)> A (9532 mgCO2·m-2 · h-1). Diurnal variation in soil respiration was not apparent due to little diurnal temperate change in Xishuangbanna. There was a parabola relationship between soil respiration and soil moisture at 1% level. Soil respiration rates were higher when soil moisture ranged from 35% to 45%. There was an exponential relationship between soil respiration and soil temperature (at a depth of 5cm in mineral soil) at 1% level. The calculated Q10 values in this study, ranging from 2.03 to 2.36, were very near to those of tropical soil reported. The CO2 efflux in 2003 was 5.34 kgCO2 · m-2 · a-1 from soil plus litter plus seedling, of them 3.48 kgCO2 · m-2 · a-1 from soil (accounting for 62.5%), 1.19 kgCO2 · m-2 · a-1 from litter (22.3%) and 0.67 kgCO2 · m-2 · a-1 from seedling (12.5%).

关键词： seasonal rain forest, soil respiration, CO2 efflux, Q10, Xishuangbanna.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Determination of atmospheric concentrations of halocarbons in beijing area

引用

Journal of Environmental sciences 1993年第1期5卷 76-82页

作者： wang ShaobinResearch Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, chinaPeng Lixin and Tang XiaoyanResearch Center of Environmental sciences, Peking University, beijing 100871, china Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China. China

Gas chromatography with ambient temperature injection and frozen-trapped techniques was used to determine the atmospheric concentrations of halocarbons over beijing. Halogenated compounds such as CFC-11, CFC-12, CHCl_3, CCl_4, CH_3CCl_3, CHCl =CCl_2, and CCl2=CCl2 were measured and their concentrations are 109±8, 234±13, 47±22, 97±24, 88±29, 11±1 and 17±3 (pptv), respectively.

关键词： GC-ECD atmospheric halocarbons beijing.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Propagation of interplanetary shock excited ultra low frequency (ULF) waves in magnetosphere-ionosphere-atmosphere——Multi-spacecraft “Cluster” and ground-based magnetometer observations

引用

Science china(Technological sciences) 2010年第9期53卷 2528-2534页

作者： wang ChengRui1,2,ZONG QiuGang1,3 & wang YongFu1 1 institute of Space physics and Applied Technology,Peking University,beijing 100871,china 2 Sate Key Laboratory of Space Weather,chinese academy of sciences,beijing 100190,china 3 Center for atmospheric Research,600 Suffolk Street,University of Massachusetts Lowell,MA 01854,USA 1. institute of Space physics and Applied Technology Peking University Beijing 100871 China2. Sate Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China3. Center for Atmospheric Research University of Massachusetts 600 Suffolk Street Lowell MA 01854 USA

The ultra low frequency (ULF) wave in magnetosphere can act as an important means for solar wind energy inward *** paper quantitatively analyzes the propagation process of the ULF wave triggered by the interplanetary shock propagating from inner magnetosphere equatorial plane along magnetic field lines to the top of the ionosphere and below ionosphere propagating process and establishes a relatively complete magnetosphere-ionosphere-atmosphere propagation model which can be used to study the relationship between the amplitude of the ULF waves triggered by the interplanetary shock wave in magnetospheric space and the magnetic effect caused by the ULF *** a comparison with recent observations,we found that: in the event during November 7,2004 that an interplanetary shock wave interacted with the magnetosphere,Cluster satellites observed that electric field fluctuations and the band-pass filtered result of ground stations meridional component had similar *** with the geomagnetic measurement near the footprints,we found that the electric field disturbance in the magnetosphere spread along the ground magnetic field lines in the form of the ULF waves and changed into geomagnetic *** result reveals that the ULF wave is in contact with the ground geomagnetic *** ULF waves couple with ionized components in ionosphere and spread to the ground in the form of electromagnetic *** this research,we believe that the magnetosphere,ionosphere and ground magnetic effects caused by interplanetary shock wave are the same physical phenomena responding in different *** on the overall consideration of entire electromagnetic response to the interplanetary shock wave,we found that the correlation between CLUSTER multi-satellite observation and geomagnetic station observation is due to the ULF wave propagated in magnetosphere-ionosphere-atmosphere system,and we quantitatively interpreted this response process

关键词： ultra low frequency (ULF) wave magnetic storm ionosphere IRI model interplanetary shock

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Debating about the climate warming

引用

Progress in Natural Science:Materials International 2006年第1期16卷 1-6页

作者： wang Shaowu1, LUO Yong2, ZHAO Zongci2, DONG Wenje2 and YANG Bao3 (1.Department of atmospheric sciences, School of physics, Peking University, beijing 100871, china 2. Laboratory for Climate Studies, china Meteorological Administration, beijing 100081, china 3. institute of Cold and Arid Regions Environmental and Engineering, chinese academy of sciences, Lanzhou 730000, china) [a] Department of atmospheric sciences School of Physics Peking University Beijing China [b] Laboratory for Climate Studies China Meterological Administration Beijing China [c] institute of Cold and Arid Regions Environmental and Engineering Chinese Academy of Sciences Lanzhou China

Debating about the climate warming is reviewed. Discussions have focused on the validity of the temperature reconstruction for the last millennium made by Mann et al. Arguments against and for the reconstruction are introduced. Temperature reconstructions by other authors are examined, including the one carried out by wang et al. in 1996. It is concluded that: (1) Ability of reproducing temperature variability of time scale less than 10 a is limited, so no sufficient evidence proves that the 1990s was the warmest decade, and 1998 was the warmest year over the last millennium. (2) All of the temperature reconstructions by different authors demonstrate the occurrence of the MWP (Medieval Warm Period) and LIA (Little Ice Age) in low frequency band of temperature variations, though the peak in the MWP and trough in LIA varies from one reconstruction to the others. Therefore, terms of MWP and LIA can be used in studies of climate change. (3) The warming from 1975 to 2000 was significant, but we do not know if it was the strongest for the last millennium, which needs to be proved by more evidence.

关键词： climate warming MWP LIA the 20th century.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Annual variation of carbon flux and impact factors in the tropical seasonal rain forest of Xishuangbanna, SW china

引用

Science china Earth sciences 2006年第S2期49卷 150-162页

作者： ZHANG Yiping, SHA Liqing, YU Guirui, SONG Qinghai, TANG Jianwei, YANG Xiaodong, wang Yuesi, ZHENG Zheng, ZHAO Shuangju, YANG Zhen & SUN Xiaomin Xishuangbanna Tropical Botanical Garden, chinese academy of sciences, Kunming 650223, china institute of Geographic sciences and National Resources Research, chinese academy of sciences, beijing 100101, china institute of atmospheric physics, chinese academy of sciences, beijing 100029, china Graduate University of chinese academy of sciences, beijing 100049, china 1. Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Kunming 650223 China 2. institute of Geographic sciences and National Resources Research Chinese Academy of Sciences Beijing 100101 China 4. Graduate University of chinese academy of sciences Beijing 100049 China 3. institute of atmospheric physics Chinese Academy of Sciences Beijing 100029 China

Two years of eddy covariance measurements of above- and below-canopy carbon fluxes and static opaque chamber and gas chromatography technique measurements of soil respiration for three treatments (bare soil, soil+litterfall, soil+litterfall+seedling) were carried out in a tropical seasonal rain forest. In addition, data of photosynthesis of dominant tree species and seedlings, leaf area index, litter production and decomposing speed, soil moisture, soil temperature and photosynthetic photon flux density within the forest were all measured concurrently. Data from January 2003 to December 2004 are used to present annual variability of carbon flux and relationships between carbon flux and impact factors. The results show that carbon flux of this forest presented unusual tendency of annual variation; above-canopy carbon fluxes were negative in the dry season (November-April) and mainly positive in the rainy season, but overall the forest is a carbon sink. Carbon flux has obviously diurnal variation in this tropical seasonal rain forest. Above-canopy carbon fluxes were negative in the daytime and absolute values were larger in the dry season than that in the rainy season, causing the forest to act as a carbon sink; at night, carbon fluxes were mainly positive, causing the forest to act as a carbon source. Dominant tree species have greater photosynthesis capability than that of seedlings, which have a great effect on above-canopy carbon flux. There was a significant correlation between above-canopy carbon flux and rate of photosynthesis of tree species. There was also a significant correlation between above-canopy carbon flux and rate of photosynthesis of seedlings; however, the below-canopy carbon flux was only significantly correlated with rate of photosynthesis of seedlings during the hot-dry season. Soil respiration of the three treatments displayed a markedly seasonal dynamic; in addition, above-canopy carbon fluxes correlated well with soil respiration, litterfall

关键词： carbon flux annual variation impact factors tropical seasonal rain forest Xishuangbanna.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Study on Middle and Short Term Forecast and Assessment Technology on Atmosphere Hydrosphere Disasters

引用

Natural Disaster Reduction in china 1998年第4期 24-29页

作者： Li Jishun,wang Angsheng,Xu Naizhang,Yang Yi and Zheng Shuangzhi (institute of atmospheric physics, chinese academy of sciences, beijing 100029)

Natural disaster is the result of abnormal natural phenomena acting on mankind. It not only relates to many natural science branches, but also closely relates to economy, property density, social development level and the vulnerability of disaster bearing bodies. Therefore, while doing disaster reduction research, we must connect natural sciences closely with human society; we should study the interplay process of nature and society and its results therefrom. Before disasters occur, based on the middle and short term disaster weather forecast, the middle and short term forecast and assessment technology of atmospheric hydrosphere disasters can forecast and assess the possible losses (the affected areas and economic losses,etc.). With the help of the disaster reduction information system and synthetic database we already set up, we have studied the law of disasters and have designed the middle and short term disaster assessment process. Through analysis of disaster situation (with the development of modern science, information and telecommunication technology, for the sake of a good command of disaster, without the presence of the disaster assessment people on the spot, it is absolutely necessary to command and to analyse the dynamics of disaster situation), through analysis of the relation between accumulative rainfall and disaster, we adopt the methods of comparative analysis of similar disasters, experience statistics model, economic measurable model and comprehensive decision,etc. to forecast and assess the losses caused by the atmospheric hydrosphere disasters such as typhoon and rainstorm 1 to 3 days ahead. The technology makes a comprehensive use of technologies of modern weather forecast, geographical information system, information process, mathematical and physical statistics, computer graph and image,*** establish day to day real time disaster assessment system under the condition of routine, satellite and radar data. In the summer of 1994 and 1995

关键词： forecast assessment middle and short term

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of elevated CO_2 on CH_4 emission

引用

chinese Science Bulletin 1999年第13期44卷 1153-1157页

作者： wang DaliState Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental sciences, chinese academy of sciences , beijing 100085, china State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Science Beijing China

Global CH4 emission may increase under CO2 enrichment condition, which is projected for the future. CO2 enrichment could affect CH4 emission in two ways: （ ⅰ ） Photosynthesis of plants that also include plants in rice paddies and natural wetlands will be stimulated under CO2 enrichment condition. CH4 emission rate may be increased due to the accumulation of more plant biomass, root exudes and soil organic matters. （ ⅱ ） Combined with other global warming forces, CO2 enrichment may bring a change of atmospheric temperature and precipitation around the world. CH4 emission will also be changed with the variation of the area and distribution of rice paddies and natural wetlands.

关键词： global change CO2 enrichment CH4 emission.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：