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Spatial and Temporal Variability of Water Availability in the Yellow River Basin

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Atmospheric and Oceanic Science Letters 2013年第4期6卷 191-196页

作者： LI Ming-Xing ma zhu-guo Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences

The changes in hydrological processes in the Yellow River basin were simulated by using the Community Land Model(CLM,version 3.5),driven by historical climate data observed from 1951 to 2008.A comparison of modeled soil moisture and runoff with limited observations in the basin suggests a general drying trend in simulated soil moisture,runoff,and precipitation-evaporation balance(P-E) in most areas of the Yellow River basin during the observation ***,annual soil moisture,runoff,and P-E averaged over the entire basin have declined by 3.3%,82.2%,and 32.1%,*** drying trends in soil moisture appear in the upper and middle reaches of the basin,whereas a significant trend in declining surface runoff and P-E occurred in the middle reaches and the southeastern part of the upper *** overall decreasing water availability is characterized by large spatial and temporal variability.

关键词： water availability variability the Yellow River basin

A Preliminary Analysis of the Relationship between Precipitation Variation Trends and Altitude in China

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Atmospheric and Oceanic Science Letters 2011年第1期4卷 41-46页

作者： YANG Qing ma zhu-guo CHEN Liang Key Laboratory of Regional Climate-Environment Research for Temperate East Asia （RCE-TEA） Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Characteristics of the relationship between precipitation variation trends (PVT) and altitude were analyzed using monthly mean precipitation data from 526 observation stations in China from 1961 to *** respect to elevation,China was divided into three subregions,below 200 m,200-1500 m,and above 1500 *** results showed that the correlations between annual PVT and altitude are different among the three *** the region below 200 m in elevation,the best relationship has a correlation coefficient of-0.19 (0.49),passing the 90% (99.9%) significance level south (north) of 35 ***,the correlation coefficient is close to zero,and the latitude strongly governs the spatial distribution of the amplitude of annual PVT in the 200-1500-m elevation *** most of the Tibetan Plateau,where the elevation is greater than 1500 m,there is a weak negative *** mann-Kendall method was used to test the trend of regional mean annual precipitation,which indicated that the annual mean precipitation had no obvious trend of change in China due to the reverse significant variation trends in different areas of the country.

关键词： precipitation tendency rate topographic effect altitude correlation

Comparison of trends and frequencies of drought in central North China and sub- Saharan Africa from 1901 to 2010

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Atmospheric and Oceanic Science Letters 2017年第6期10卷 418-426页

作者： Faustin Katchele OGOU ma zhu-guo YANG Qing Batebana KPAIKPAI CAS Key Laboratory of Regional Climate-Environment forTemperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China College of Earth Science University of Chinese Academy of Sciences Beijing China Meteorology Department of Benin Cotonou Benin

This study compares the trends and frequencies of drought between central North China(CNC) and(SSA) for the periods 1901–2010 and 1951–2010. The Standardized Precipitation Evapotranspiration Index(SPEI) and Self-Calibrating Palmer Drought Severity Index(sc-PDSI) are used to assess the drought trends and frequencies. In general, the results exhibit downward trends of drought index values and upward trends of drought frequencies over CNC and SSA. A high rate of the trends' slopes for the drought index and a low rate of the frequencies' slopes is found over CNC with respect to SPEI and sc-PDSI. Furthermore, some abrupt changes are revealed after applying the sequential mann–Kendall test to detect change points. These findings offer insight into the trends and frequencies of drought over the regions studied. Further analysis needs to be undertaken to understand the mechanisms underlying the occurrence of drought in these areas.

关键词： Drought trends frequencies central North China sub-Saharan Africa

Evaluation of the WRF Model with Different Land Surface Schemes: A Drought Event Simulation in Southwest China during 2009–10

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Atmospheric and Oceanic Science Letters 2014年第2期7卷 168-173页

作者： HU Zu-Heng XU Zhong-Feng ZHOU Ning-Fang ma zhu-guo LI guo-Ping Key Laboratory of Regional Climate-Environment Research for East Asia Institute of Atmospheric Physics Chinese Academy of Sciences College of Atmospheric Sciences Chengdu University of Information Technology Young Scientists Laboratory Institute of Atmospheric Physics Chinese Academy of Sciences National Meteorological Center China Meteorological Administration

The authors examined the performance of version 3.4.1 of the Weather Research and Forecasting Model(WRF) with various land surface schemes in simulating a severe drought event in Southwest China. Five numerical experiments were completed using the Noah land surface scheme, the Pleim-Xiu land surface scheme, the Noah-MP land surface schemes, the Noah- MP scheme with dynamic vegetation, and the Noah-MP scheme with dynamic vegetation and groundwater processes. In general, all the simulations reasonably reproduced the spatial and temporal variations in precipitation, but significant bias was also found, especially for the spatial pattern of simulated precipitation. The WRF simulations with the Noah-MP series land surface schemes performed slightly better than the WRF simulation with the Noah and Pleim-Xiu land surface schemes in reproducing the severe drought events in Southwest China. The leaf area index(LAI) simulated by the different land surface schemes showed significant deviations in Southwest China. The Pleim-Xiu scheme overestimated the value of LAI by a factor of two. The Noah-MP scheme with dynamical vegetation overestimated the magnitude of the annual cycle of the LAI, although the annual mean LAI was close to observations. The simulated LAI showed a long-term lower value from autumn 2009 to spring 2010 relative to normal years. This indicates that the LAI is a potential indictor to monitor drought events.

关键词： land surface model drought Southwest China Noah-MP precipitation leaf area index

Development of a High Sound Absorption material CEMCOM

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Journal of Wuhan University of Technology(materials Science) 2002年第4期17卷 5-8页

作者：马保国 School of materials Science and Engineering Whan University of Technology Wuhan China

Based on sound absorption mechanism of material,the special sound absorption material CEMCOM for road sound insulation is *** high sound absorption material is mainly composed of expanded *** multiple sound absorption structure can improve sound absorption property of *** to the preparation principle and durability design of material,a new kind of material with low cost and high durability is developed.

关键词： sound absorption coefficient sound absorption structure porous material

Simulation of the regional climatic effect of irrigation over the Yellow River Basin

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Atmospheric and Oceanic Science Letters 2017年第4期10卷 291-297页

作者： CHEN Liang ma zhu-guo ZHAO Tian-Bao LI Zhen-Hua LI Yan-Ping CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Global Institute for Water Security University of Saskatchewan

In this study, the authors developed a new irrigation scheme based on the Noah land surface model, and then coupled it with the Weather Research and Forecasting regional climate model. Two simulations （with and without irrigation） were conducted over the Yellow River basin for the period April to October 2000-2010. The results indicated that the WRF model is able to successfully capture the spatial pattern and seasonal changes in observed temperature and precipitation over the Yellow River basin. When irrigation was induced, the mean surface air temperature at 2 m （T2m） decreased by 0.1-0.4 K, and there was a correspond increase （decrease） in latent （sensible） heat flux over the irrigated areas, wherein the increase （decrease） reached more than 10 W m-2 over the largest irrigated areas. The cooling effect was consistent with the changes in evapotranspiration and heat fluxes due to *** changes in lifting condensation level and planetary boundary layer height led to a greater probability of cloud formation and bore a close association with surface fluxes and soil moisture, which then impacted the spatial distribution of T2rn and precipitation.

关键词： Irrigation WRF regionalclimate

我国北方干湿演变规律及其与区域增暖的可能联系

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地球物理学报 2005年第5期48卷 1011-1018页

作者：马柱国中国科学院东亚区域气候-环境重点实验室中国科学院大气物理研究所全球变化东亚研究中心北京100029

用中国地区60个站的月平均气温和月降水资料,计算了我国北方地区地表水分收支、蒸发等水分过程.以此为基础,分析了三北地区(西北、东北和华北)地表水分的历史演变规律及其与气温变化的关系,特别分析了和区域增暖的关系.结果指出:在北方... 详细信息

用中国地区60个站的月平均气温和月降水资料,计算了我国北方地区地表水分收支、蒸发等水分过程.以此为基础,分析了三北地区(西北、东北和华北)地表水分的历史演变规律及其与气温变化的关系,特别分析了和区域增暖的关系.结果指出:在北方地区,地表水分有其显著的演变规律,不同地区其变化规律不同.而实际蒸发和气温的关系存在明显的阶段性,在1965年前与1965年后的相关关系是完全相反的.分析的结果还指出:当前北方地区的普遍增温是干旱化加剧的主要原因.

关键词：中国北方干湿演变区域增暖影响强度指数

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黄河径流量的历史演变规律及成因

地球物理学报 2005年第6期48卷 1270-1275页

作者：马柱国中国科学院大气物理研究所东亚区域气候-环境重点实验室中国科学院大气物理研究所东亚中心北京100029

基于黄河上、中和下游的径流及气候资料,对径流的年代际变化规律及与气候变化的关系进行了分析.结果表明:黄河流域的径流均存在显著的年代际变化趋势,径流的显著特征是从20世纪80年代开始的减少趋势,但并未达到历史的最低,径流减少的趋... 详细信息

基于黄河上、中和下游的径流及气候资料,对径流的年代际变化规律及与气候变化的关系进行了分析.结果表明:黄河流域的径流均存在显著的年代际变化趋势,径流的显著特征是从20世纪80年代开始的减少趋势,但并未达到历史的最低,径流减少的趋势在下游比上游更显著,而这种变化趋势与流域的气候变化趋势基本一致,说明在年代际尺度上,径流的变化主要受气候的控制;在不同季节,这种关系有明显差异,如在冬季两者的变化趋势有较大差异.分析还发现,近年来流域地表的干化是流域径流减少的原因,气温的升高更加剧了流域地表干化.

关键词：黄河径流变化趋势湿润指数增暖

Modeling Gross Primary Production by Integrating Satellite Data and Coordinated Flux Measurements in Arid and Semi-Arid China

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Atmospheric and Oceanic Science Letters 2010年第1期3卷 7-13页

作者： WANG He-Song JIA Gen-Suo FENG Jin-Ming ZHAO Tian-Bao ma zhu-guo Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beo＇ing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Assessing large-scale patterns of gross primary production (GPP) in arid and semi-arid (ASA) areas is important for both scientific and practical *** sensing-based models,which integrate satellite data with input from ground-based meteorological measurements and vegetation characteristics,improve spatially extended estimates of vegetation productivity with high *** this study,the authors simulated GPP in ASA areas by integrating moderate resolution imaging spectral radiometer (MODIS) data with eddy covariance and meteorological measurements at the flux tower sites using the Vegetation Photosynthesis Model (VPM),which is a remote sensing-based model for analyzing the spatial pattern of GPP in different land cover *** field data were collected by coordinating observations at nine stations in *** results indicate that in the region during the growing season GPP was highest in cropland sites,second highest in woodland sites,and lowest in grassland *** captured the temporal and spatial characteristics of GPP for different land covers in ASA ***,Enhanced Vegetation Index (EVI) had a strong liner relationship with GPP in densely vegetated areas,while the Normalized Difference Vegetation Index (NDVI) had a strong liner relationship with GPP over less dense *** study demonstrates the potential of satellite-driven models for scaling-up GPP,which is a key component for studying the carbon cycle at regional and global scales.

关键词： gross primary production vegetation photo- synthesis model eddy covariance remote sensing coordinated observation arid and semiarid areas