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Runoff reduction due to environmental changes in the Sanchuanhe river basin

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International Journal of Sediment research 2008年第2期23卷 174-180页

Recently,runoff in many river basins in China has been ***,the role that climate change and human activities are playing in this decrease is currently of *** this study,we evaluated an assessment method that was designed to quantitatively separate the effects of climate change and human activities on runoff in river ***,we calibrated the SIMHYD rainfall runoff model using naturally recorded hydro-meteorologic data pertaining to the Sanchuanhe River basin and then determined the effects of climate change and human activities on runoff by comparing the estimated natural runoff that occurred during the period in which humans disturbed the basin to the runoff that occurred during the period prior to disturbance by *** results of this study revealed that the SIMHYD rainfall runoff model performs well for estimating monthly *** addition,we found that absolute runoff reductions have increased in response to human activities and climate change,with average reductions of 70.1% and 2..9% in total runoff being caused by human activities and climate change,*** together,the results of this study indicate that human activities are the primary cause of runoff reduction in the Sanchuanhe River basin.

关键词： Sanchuanhe River Hydrological simulation climate change Human activities Impact

Top 10 Influential Events in carbon neutrality and climate change response for 2.2.

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Frontiers in Energy 2024年第1期18卷 1-3页

作者： research Institute of Carbon Neutrality of Shanghai Jiao Tong University research Institute of Carbon Neutrality Shanghai Jiao Tong UniversityShanghai 200240China

In 2.2., the global community intensified its efforts towards achieving carbon neutrality and addressing climate change, witnessing several impactful events. {2. Institute of Carbon Neutrality, Shanghai Jiao Tong University compiled the Top 10 Events (in chronological order) in the field of global carbon neutrality and climate change response for 2.2., to share with readers these significant moments that document the ongoing ambition and collective efforts of human society.

关键词： neutral collective intensified

Dynamic behavior of fragile X full mutations in cultured female fetal fibroblasts

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Acta Pharmacologica Sinica 2004年第7期25卷 127-130页

作者： Yu-jie SUN1,2.Xiao HAN1,3 1Laboratory of Functional Genomics at nanjing Medical University, nanjing 2.002., China 2.ivision of Molecular Medicine in Beckman {2. Institute, Leslie and Susan Gonda (Goldschmied) Diabetes 3 and Genetics {2. center, City of Hope National Medical center, Duarte, California Laboratory of Functional Genomics at nanjing Medical University China City of Hope National Medical center Duarte California

AIM: Toassess mitotic stability ofthe fragile X fullmutations andits relationshipwith DNA methylation. METHODS: The length change of the expanded CGG repeats was examined and correlated it with the methylation status in the DNA samplesisolated fromthe fibroblasts derived from a fragile Xfemale fetus anda fragileX maleadult, respectively. RESULTS: A dramatic instability of the expanded CGG repeats in the female fetal fibroblasts was observed. South- ern blot analysis revealed that the 6.9-kb major expanded band detected in passage 2.was completely replaced by a 7.7-kb band after passage 30. Fibroblast clones derived from the passage 3 displayed an unstable expansion of the CGG repeat during clonal proliferation, while methylation status of the CGG repeat region was maintained. In contrast, in fragile X male fibroblasts the expanded CGG repeats were stable during clonal proliferation. CONCLUSION: The mitotic instability of expanded CGG repeat is not always restricted in early development window as proposed previously and other elements rather than DNA methylation could affect the stability of the expanded CGG repeats in fragile X female fetal fibroblast cells.

关键词： DNA female fetus fibroblasts fragile X syndrome heterozygote human mutation X chromo- some

Prediction model for spring dust weather frequency in North China

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Science China Earth Sciences 2008年第5期51卷 709-720页

作者： LANG XianMei center for Disastrous climate {2. and Prediction, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., China center for Disastrous climate {2. and Prediction Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

It is of great social and scientific importance and also very difficult to make reliable prediction for dust weather frequency (DWF) in North China. In this paper, the correlation between spring DWF in Beijing and Tianjin observation stations, taken as examples in North China, and seasonally averaged surface air temperature, precipitation, Arctic Oscillation, Antarctic Oscillation, South Oscillation, near surface meridional wind and Eurasian westerly index is respectively calculated so as to construct a prediction model for spring DWF in North China by using these climatic factors. Two prediction models, i.e. model-I and model-II, are then set up respectively based on observed climate data and the 32.year (1970 -2.01) extra-seasonal hindcast experiment data as reproduced by the nine-level Atmospheric General Circulation Model developed at the Institute of Atmospheric Physics (IAP9L-AGCM). It is indicated that the correlation coefficient between the observed and predicted DWF reaches 0.933 in the model-I, suggesting a high prediction skill one season ahead. The corresponding value is high up to 0.948 for the subsequent model-II, which involves synchronous spring climate data reproduced by the IAP9L-AGCM relative to the model-I. The model-II can not only make more precise prediction but also can bring forward the lead time of real-time prediction from the model-I’s one season to half year. At last, the real-time predictability of the two models is evaluated. It follows that both the models display high prediction skill for both the interannual variation and linear trend of spring DWF in North China, and each is also featured by different advantages. As for the model-II, the prediction skill is much higher than that of original approach by use of the IAP9L-AGCM alone. Therefore, the prediction idea put forward here should be popularized in other regions in China where dust weather occurs frequently.

关键词： spring dust weather frequency prediction model iap9l-agcm hindcast experiment real-time prediction

Turbulent intensity and its similarity function over an Inner Mongolian grassland during spring

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Science China Earth Sciences 2010年第5期53卷 773-780页

作者： YUE Ping1,2.3, NIU ShengJie2. HU YinQiao4 & ZHANG Qiang1 1 Key Laboratory of Arid climate change and Reducing Disaster of Gansu Province, Key Laboratory of Arid climate change and Reducing Disaster of CMA, Institute of Arid Meteorology, CMA, Lanzhou 73002., China 2.nanjing University of Information Science and Technology, nanjing 2.0044, China 3 Zhangye National Meteorological Observatory, Zhangye 734000, China 4 Cold and Arid Regions Environmental and Engineering research Institute, Chinese Academy of Science, Lanzhou 730000, China 1. Key Laboratory of Arid climate change and Reducing Disaster of Gansu Province Key Laboratory of Arid Climate Change and Reducing Disaster of CMA Institute of Arid Meteorology CMA Lanzhou 730020 China2. Nanjing University of Information Science and Technology Nanjing 210044 China3. Zhangye National Meteorological Observatory Zhangye 734000 China4. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Science Lanzhou 730000 China

Macroscopic reason for the development of turbulences in fluid is the conjunction action of velocity and temperature shears. We use the 2.08 spring flux observations in the surface layer over Inner Mongolian grassland, obtain the similarity functions of turbulent intensity under different stratification stability conditions, and calculate the clear day turbulent intensity in the spring, which is then analyzed and compared with the observed values of turbulent intensity. The results show that in the Inner Mongolian grassland, under the condition of spring unstable stratification of the surface layer, dependence of the similarity function of turbulent intensity on stratification stability follows a "2.3 power law". The structural function is a constant under the neutral stratification condition, and complicated under the stable condition. The calculated turbulent intensity has a close correlation with the observed one, which verifies the accuracy of the similarity functions and the suitability of the theorem of turbulent intensity in the grassland region.

关键词： turbulent intensity variance of velocity similarity function grassland

Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science China Earth Sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2. KANG Shichang2.3,5, SUN Junying4,5, Paul A. Mayewski2.& QIN Dahe5 1. National climate center, China Meteorological Administration, Beijing 100081, China 2. climate change Institute, University of Maine, Orono, ME 04469, USA 3. Institute of Tibetan Plateau research, Chinese Academy of Sciences, Beijing 100085, China 4. Chinese Academy of Meteorological Sciences, Beijing 100081, China 5. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Environmental and Engineering research Institute, Chinese Academy of Sciences, Lanzhou 730000, China 1. National climate center China Meteorological Administration 100081 Beijing China 2. climate change Institute University of Maine 04469 Orono ME USA 3. Institute of Tibetan Plateau research Chinese Academy of Sciences 100085 Beijing China 4. Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China 5. Chinese Academy of Meteorological Sciences 100081 Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 2.D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 2.D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (2.D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

research on stability of the accumulated rock-soil body of reservoir bank under rainfall condition

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Science China(Technological Sciences) 2009年第9期52卷 2528-2535页

作者： GU ChongShi1,2.WU HaiZhen1,2.& SU HuaiZhi1,2.1 College of Water Resources and Hydropower Engineering,Hohai University,nanjing 2.0098,China 2.National Engineering research {2. of Water Resources Efficient Utilization and Engineering Safety,Hohai University,nanjing 2.0098,China 3 Jiangxi Water Conservancy research Institute,Nanchang 33002.,China 1. College of Water Resources and Hydropower Engineering Hohai University Nanjing 210098 China 2. National Engineering research center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing 210098 China 3. Jiangxi Water Conservancy research Institute Nanchang 330029 China

The shear strength parameters property of rock-soil aggregates in embankment slope of reservoir,that is,the relationship between cohesion and gravel content,between friction angle and gravel content,and the relationship between cohesion and water content,between friction angle and water content,is studied based on the direct shear test results,the shear strength change law of the rock-soil aggregates is given,and the unsaturated shear strength formulation of rock-soil aggregates that could consider suction and saturation degree influence is put forward in this paper,through which the sliding or failure physical mechanism of this type of slope under the condition of rainfall infiltration is studied. Also the 3D unsteady saturated-unsaturated seepage field and its FEM resolving mode are established based on the analysis of the slope rainfall infiltration process. Case study with this method indicates that the minimum safety factor of the accumulated rock-soil aggregates dose not arrive at the moment of rainfall cessation,but appears several hours after the rainfall cessation,this phenomenon is in accordance with the practical slope engineering's failure process and could explain appropriately the slope failure caused by rainfall infiltration. research results in this paper have an important reference value for the research on stability of the accumulated rock-soil aggregates in embankment slope of reservoir,and can enrich the stability analysis method and relevant theory of reservoir embankment slope.

关键词： reservoir bank slope rock-soil aggregates rainfall infiltration saturated/unsaturated seepage

A three-dimensional variational ocean data assimilation system:Scheme and preliminary results

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Science China Earth Sciences 2006年第11期49卷 1212-1222页

作者： ZHU Jiang1,2. ZHOU Guangqing1, YAN Changxiang1, FU Weiwei1 & YOU Xiaobao1,3 1. International center for climate and Environment Sciences, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., China 2. Jiangsu Key Laboratory of Meteorological Disaster, {2. University of Information Science and Technology, {2. 2.0044, China 3. Beijing Institute of Applied Meteorology, Beijing 10002., China 1. International center for climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Jiangsu Key Laboratory of Meteorological Disaster Nanjing University of Information Science and Technology Nanjing 210044 China 3. Beijing Institute of Applied Meteorology Beijing 100029 China

A new 3DVAR-based Ocean Variational Analysis System (OVALS) is developed. OVALS is capable of assimilating in situ sea water temperature and salinity observations and satellite altimetry data. As a component of OVALS, a new variational scheme is proposed to assimilate the sea surface height data. This scheme considers both the vertical correlation of background errors and the nonlinear temperature-salinity relationship which is derived from the generalization of the linear balance constraints to the nonlinear in the 3DVAR. By this scheme, the model temperature and salinity fields are directly adjusted from the altimetry data. Additionally, OVALS can assimilate the temperature and salinity profiles from the ARGO floats which have been implemented in recent years and some temperature and salinity data such as from expendable bathythermograph, moored ocean buoys, etc. A 2.-year assimilation experiment is carried out by using OVALS and the Tropical Pacific circulation model. The results show that the assimilation system may effectively improve the estimations of temperature and salinity by assimilating all kinds of observations. Moreover, the root mean square errors of temperature and salinity in the upper depth less than 42. m reach 0.63℃ and 0.34 psu.

关键词： data assimilation, 3DVAR, sea surface height, ARGO floats.

Modeling the climate effects of different subregional uplifts within the Himalaya-Tibetan Plateau on Asian summer monsoon evolution

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Chinese Science Bulletin 2012年第35期57卷 4617-4626页

Considering the different uplifting time of different subregions of the Himalaya-Tibetan Plateau(TP),a series of numerical simulations have been conducted with the Community Atmosphere Model(CAM4) developed at the National center for Atmospheric research to explore the effects of the phased tectonic uplift of the Himalaya-TP on the evolution of Asian summer *** results show that the uplifts of the Himalaya and northern TP significantly affect the evolutions of South Asian summer monsoon and northern East Asian summer monsoon *** is,the tectonic uplift of the Himalaya intensifies the South Asian summer monsoon circulation and increases the precipitation in South Asia,whereas the uplift of the northern TP intensifies the northern East Asian summer monsoon circulation and increases the precipitation in northern East *** with previous simulations,current comparative analyses of modeling results for different subregional uplifts within the Himalaya-TP help deepen our understanding of the evolutionary history of Asian monsoons.

关键词：青藏高原隆升喜马拉雅亚洲季风高原气候夏季季风次区域隆起演化建模