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黄石坳保护区的兽类初步研究 被引量:2
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作者 彭红元 吴毅 +1 位作者 江海声 胡锦矗 《四川师范学院学报(自然科学版)》 2003年第2期145-150,共6页
2002年5-7月对广东和平县黄石坳保护区的兽类进行了调查,共记录到兽类6目15科31种,东洋型21种占67.7%;南中国型5种占16.1%;古北型3种占9.7%;季风型和喜马拉雅山型各1种占3.2%.其中国家Ⅰ级保护动物1种;Ⅱ级保护动物5种;三有动物10种,说... 2002年5-7月对广东和平县黄石坳保护区的兽类进行了调查,共记录到兽类6目15科31种,东洋型21种占67.7%;南中国型5种占16.1%;古北型3种占9.7%;季风型和喜马拉雅山型各1种占3.2%.其中国家Ⅰ级保护动物1种;Ⅱ级保护动物5种;三有动物10种,说明该地区物种珍稀程度较高.翼手类共记录到12种,占所有物种总数的38.7%;啮齿类只有3种,占种数的9.6%,可能与捕获的季节等有关. 展开更多
关键词 黄石坳保护区 兽类 东洋 南中国型 古北 季风 喜马拉雅山 翼手类 啮齿类
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Response of Asian Summer Monsoon to CO_2 Doubling 被引量:2
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作者 ZHENG Jian LIU Qinyu HUANG Fei 《Journal of Ocean University of China》 SCIE CAS 2011年第3期210-218,共9页
Based on simulations of the IPCC 20C3M and SRES A1B experiments in ten coupled models, the Asian summer mon-soon (ASM) response to CO2 doubling and the different responses among models are examined. Nine models show t... Based on simulations of the IPCC 20C3M and SRES A1B experiments in ten coupled models, the Asian summer mon-soon (ASM) response to CO2 doubling and the different responses among models are examined. Nine models show the similar results that the weakening of land-ocean thermal contrast caused by the CO2 doubling contributes to a weaker large-scale ASM circulation. Further analysis in this study also shows that the major ASM components,such as the Somali cross-equatorial flow,the low level India-South China Sea monsoon trough,and the upper level tropical easterly jet stream, weaken as CO2 doubles.However,the ASM rainfall increases as a result of the increased moisture from the warmer Indian Ocean and the South China Sea, and the enhanced northward moisture transport over the ASM region.For the response of enhanced northward moisture transport over South Asia, the positive contribution of moisture content increase in the Indian Ocean is dominant and the negative contribution of the weaker mon-soon circulation is secondary at 850 hPa,but both have positive contribution to the total moisture transport along the East China coast.The paradox of the weaker ASM circulation and the increasing precipitation in CO2 doubling is confirmed.It is found that strengthening of northward moisture transport could intensify the precipitation and atmospheric heat source over the north Arabian Sea and East China,and result in enhanced southwesterly at 850 hPa as global warming occurs.All ten models show significant enhanced southwesterly response over the north Arabian Sea,and six of them show enhanced southwesterly response along the East China coast. 展开更多
关键词 CO2 doubling IPCC 4th Assessment report Asian summer monsoon
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A study of groundwater irrigation water quality in south-central Bangladesh: a geo-statistical model approach using GIS and multivariate statistics 被引量:3
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作者 M.Atikul Islam Md.Mostafizur Rahman +5 位作者 Md.Bodrud-Doza Md.Iftakharul Muhib Mashura Shammi Anwar Zahid Yeasmin Akter Masaaki Kurasaki 《Acta Geochimica》 EI CAS CSCD 2018年第2期193-214,共22页
Southern Bangladesh's irrigation and drinking water is threatened by saline intrusion. This study aimed to establish an irrigation water quality index (IWQI) using a geostatistical model and multivariate indices in... Southern Bangladesh's irrigation and drinking water is threatened by saline intrusion. This study aimed to establish an irrigation water quality index (IWQI) using a geostatistical model and multivariate indices in Gopalganj district, south-central Bangladesh. Groundwater samples were taken randomly (different depths) in two seasons (wet-monsoon and dry-monsoon). Hydrochemical analysis revealed groundwater in this area was neutral to slightly alkaline and dominating cations were Na^+, Mg^2+, and Ca^2+ along with major anions Cl^- and HCO3^-. Principal component analysis and Gibbs plot helped explain possible geochemical processes in the aquifer. The irrigation water evaluation indices showed: electrical conductivity (EC) 〉750 μS/cm, moderate to extreme saline; sodium adsorption ratio (SAR), excellent to doubtful; total hardness (TH), moderate to very hard; residual sodium bicarbonate, safe to marginal; Kelly's ratio 〉1; soluble sodium percentage (SSP), fair to poor; magnesium adsorption ratio, harmful for soil; and IWQI, moderate to suitable. In addition, the best fitted semivariogram for IWQI, EC, SAR, SSP, and TH confirmed that most parameters had strong spatial dependence and others had moderate to weak spatial dependence. This variation might be due to the different origin/sources of major contributing ions along with the influence of variable river flow and small anthropogenic contributions. Furthermore, the spatial distribution maps for IWQI, EC, SSP, and TH during both seasons confirmed the influence of salinity from the sea; low-flow in the major river system was the driving factor of overall groundwater quality in the study area. These findings may contribute to management of irrigation and/or drinking water in regions with similar groundwater problems. 展开更多
关键词 SEMIVARIOGRAM Ordinary kriging model Salinity Irrigation water quality index GIS HYDROCHEMISTRY
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Goethite Morphologies of Some Soils in South of Central China 被引量:2
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作者 LIUFAN XUFENG-LIN 等 《Pedosphere》 SCIE CAS CSCD 1994年第3期193-200,共8页
The morphologies of goethites in latosol, red soils, yellow-brown soil and the paddy soils developed from red soils were studied in comparison with the morphology of synthetic goethite by means of the X-ray distractio... The morphologies of goethites in latosol, red soils, yellow-brown soil and the paddy soils developed from red soils were studied in comparison with the morphology of synthetic goethite by means of the X-ray distraction, transmission electron microscopy and energy dispersive X-ray analysis. The synthetic goethite displayed acicular particles elongated in the c-direction. The goethites in the latosol, red soils and yellowbrown soil were platy particles stretched in two directions or isodimensional particles, and those in the paddy soils from red soils were acicular, short columnar, platy or isodimensional particles. Various morphologies of the goethites probably suggested their different dominant crystal faces, surface charge distribution and surface adsorption characteristics. 展开更多
关键词 goethites MORPHOLOGY SOILS surface adsorption surface charge
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An isopycnic-coordinate internal tide model and its application to the South China Sea 被引量:6
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作者 苗春葆 陈海波 吕咸青 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第6期1339-1356,共18页
A three-dimensional isopycnic-coordinate ocean model for the study of internal tides is presented. In this model, the ocean interior is viewed as a stack of isopycnic layers, each characterized by a constant density. ... A three-dimensional isopycnic-coordinate ocean model for the study of internal tides is presented. In this model, the ocean interior is viewed as a stack of isopycnic layers, each characterized by a constant density. The isopycnic coordinate performs well at tracking the depth variance of the thermocline, and is suitable for simulation of internal tides. This model consists of external and internal modes, and barotropic and baroclinic motions are calculated in the two modes, respectively. The capability of simulating internal tides was verified by comparing model results with an analytical solution. The model was then applied to the simulation of internal tides in the South China Sea (SCS) with the forcing of M2 and K1 tidal constituents. The results show that internal tides in the SCS are mainly generated in the Luzon Strait. The generated M2 internal tides propagate away in three different directions (branches). The branch with the widest tidal beam propagates eastward into the Pacific Ocean, the most energetic branch propagates westward toward Dongsha Island, and the least energetic branch propagates southwestward into the basin of the SCS. The generated KI internal tides propagate in two different directions (branches). One branch propagates eastward into the Pacific Ocean, and the other branch propagates southwestward into the SCS basin. The steepening process of internal tides due to shoaling effects is described briefly. Meridionally integrated westward energy fluxes into the SCS are comparable to the meridionally integrated eastward energy fluxes into the Pacific Ocean. 展开更多
关键词 internal tides isopycnic coordinate numerical simulation South China Sea (SCS)
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Geological significance of nickeliferous minerals in the Fule Pb–Zn deposit, Yunnan Province, China 被引量:6
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作者 Zhenli Li Lin Ye +1 位作者 Yusi Hu Zhilong Huang 《Acta Geochimica》 EI CAS CSCD 2018年第5期684-690,共7页
Abstract The Fule Pb-Zn deposit is located in the Sichuan-Yunnan-Guizhou Province, and it is an important and giant low temperature metallogenic domain in China. In our research area, the Pb-Zn deposits are mainly hos... Abstract The Fule Pb-Zn deposit is located in the Sichuan-Yunnan-Guizhou Province, and it is an important and giant low temperature metallogenic domain in China. In our research area, the Pb-Zn deposits are mainly hosted in the Permian Yangxin Formation and are composed of dolostone and limestone. The distance between the ore bodies and the Permian Emeishan basalt ranged from 50 to 160 m. In this study, the nickel rich minerals, including vaesite, polydymite and millerite, were reported for the first time in the Fule deposit. These minerals occurred as xenomorphic mineral aggregate and were sporadically distributed in the sphalerite-galena-calcite vein, which is the main ore type in the deposit. Our study indicated that the paragenetic sequence of minerals in the Fule deposit is the following order: polydymite → vaesite → mil- lerite → sphalerite → galena → tetrahedrite (tennantite). The geological occurrence characteristics of those nicke- liferous minerals suggested that the Permian Emeishan basalt is a possible barrier layer of Pb-Zn ore-forming fluid, and it is an important source for the Ni and part of the Cu in the deposit. The Sichuan-Yunnan-Guizhou Pb-Zn mineralization province is a world-class production base of Pb and Zn, in which the Permian Emeishan basalt and Pb- Zn deposits have uniformly spatial distribution, but the relationship of mineralization between them is still under debate. This report provides new evidence for understanding the relationship between Pb-Zn mineral- ization and Permian Emeishan basalt in the Sichuan- Yunnan-Guizhou Pb-Zn mineralization province. 展开更多
关键词 Nickeliferous Permian Emeishan basalt Fule Pb-Zn deposit MVT deposit Barrier layer
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Evaluation of the WRF Model with Different Land Surface Schemes: A Drought Event Simulation in Southwest China during 2009–10 被引量:2
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作者 HU Zu-Heng XU Zhong-Feng +2 位作者 ZHOU Ning-Fang MA Zhu-Guo LI Guo-Ping 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第2期168-173,共6页
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 experi... 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. 展开更多
关键词 land surface model DROUGHT Southwest China Noah-MP precipitation leaf area index
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Simulation of Extreme Climate Events over China with Different Regional Climate Models 被引量:9
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作者 FENG Jin-Ming WANG Yong-Li FU Cong-Bin 《Atmospheric and Oceanic Science Letters》 2011年第1期47-56,共10页
During phase II of the Regional Climate Model Inter-comparison Project (RMIP) for Asia, the Asian climate was estimated from July 1988 to December 1998 using six climate models. In this paper, the abilities of six c... During phase II of the Regional Climate Model Inter-comparison Project (RMIP) for Asia, the Asian climate was estimated from July 1988 to December 1998 using six climate models. In this paper, the abilities of six climate models to simulate several important ex- treme climate events in China during the last years of the last century were analyzed. The modeled results for the intensity of the precipitation anomaly over the Yang- tze-Huaihe Valley during the summers of 1991 and 1998 were weaker than the observed values. The positive pre- cipitation anomaly responsible for a catastrophic flood in 1991 was well reproduced in almost all simulation results, but the intensity and range of the precipitation anomaly in 1998 were weaker in the modeled results. The spatial dis- tribution of extreme climate events in 1997, when severe drought affected North China and flood impacted South China, was reproduced by most of the regional models because the anomaly of the large-scale background field was well-simulated, despite poor simulation of high temperature areas in the north during the summer by all models. 展开更多
关键词 RMIP extreme climate event FLOOD DROUGHT spatial distribution
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Timing and structural controls on skarn-type and vein-type mineralization at the Xitian tin-polymetallic deposit, Hunan Province, SE China 被引量:5
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作者 Miao He Quanlin Hou +4 位作者 Qing Liu Jiheng Zhang Jinfeng Sun Shichong Wu Haofeng Zhu 《Acta Geochimica》 EI CAS CSCD 2018年第2期295-309,共15页
Xitian tin-polymetallic deposit, located in the eastern Hunan Province, SE China, hosts quartz vein and skarn in the contact zone between carbonate and two stages granites. Critical geodynamic questions for South Chin... Xitian tin-polymetallic deposit, located in the eastern Hunan Province, SE China, hosts quartz vein and skarn in the contact zone between carbonate and two stages granites. Critical geodynamic questions for South China are whether different types of mineralization form in the same time and how the magmatism–tectonic system controls the ore-forming process. Based on the distribution of the orebodies, six cassiterite samples from different types of mineralization are collected for dating. In-situ LA-MCICP-MS U–Pb isotopic data yielded concordia low intercept ages between 154 and 157 Ma, indicating that different types of mineralization belong to the same magmatism–mineralization system. Coupled with the study of the kinematic indicators, it suggests that the structural control of the wall rocks constrain the types of mineralization. These results provide further evidence of a close temporal link between the structure and the tin-polymetallic mineralization in Xitian deposit. Considering the structure in the district, granite dome plays an important role in the ore-forming process. The age and structural signatures in Xitian deposit are the response to the subduction of Pacific Plate. 展开更多
关键词 LA-MC-ICP-MS U-Pb dating Structure control Tin-polymetallic deposit SE China
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Submesoscale activity over the shelf of the northern South China Sea in summer:simulation with an embedded model 被引量:2
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作者 刘国强 何宜军 +1 位作者 申辉 丘仲锋 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第5期1073-1079,共7页
We applied a primitive equation ocean model to simulate submesoscale activities and processes over the shelf of the northern South China Sea(NSCS) with a one-way nesting technology for downscaling.The temperature and ... We applied a primitive equation ocean model to simulate submesoscale activities and processes over the shelf of the northern South China Sea(NSCS) with a one-way nesting technology for downscaling.The temperature and density fields showed that submesoscale activities were ubiquitous in the NSCS shelf.The vertical velocity was considerably enhanced in submesoscale processes and could reach an average of 58 m per day in the subsurface.At this point,the mixed layer depth also was deepened along the front,and the surface kinetic energy also increased with the intense vertical movement induced by submesoscale activity.Thus,submesoscale stirring/mixing is important for tracers,such as temperature,salinity,nutrients,dissolved organic,and inorganic carbon.This result may have implication for climate and biogeochemical investigations. 展开更多
关键词 submesoscale activity vertical pumping northern South China Sea (NSCS)
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Geochemistry,petrogenesis and tectonic significance of the late Triassic A-type granite in Fujian,South China 被引量:1
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作者 Dawei Cai Jingyu Zhao +3 位作者 Yong Tang Hui Zhang Yunlong Liu Zhenghang Lv 《Acta Geochimica》 EI CAS CSCD 2017年第2期166-180,共15页
The late Permian–Triassic granites in southeastern China have important tectonic significance for the evolution of South China. Here, we present the detailed geochronological, geochemical and petrological analyses fo... The late Permian–Triassic granites in southeastern China have important tectonic significance for the evolution of South China. Here, we present the detailed geochronological, geochemical and petrological analyses for the Jinlongyan(JLY) granite in northwest Fujian Province, southeast China. LA–ICP–MS zircon U–Pb dating yielded a weighted average ^(206)Pb/^(238)U age of 224.1 ±3.3 Ma. The granite is mainly comprised of K-feldspar,plagioclase, quartz, biotite and minor amphibole. It is characterized by enrichments in Rb, Th, REEs(total REE = 295.1–694.3 ppm), and HFSEs(e.g., Zr = 289–520 ppm, Hf = 9.3–15.0 ppm, Y = 36.2–68.2 ppm) but depletions in Ba, Sr, Eu and Ti. The granite is metaluminous to weakly peraluminous and show a clear A-type granite geochemical signature with high SiO_2(70.89 wt%–75.76 wt%), total alkalis(Na_2O + K_2O = 7.51 wt%–8.72 wt%), Ga/Al ratios(10000 Ga/Al = 2.72–3.43). Insitu zircon Hf isotope analysis shows their eHf(t) values ranging from-7.2 to-3.2, with Mesoproterozoic T2DM ages(1308–1525 Ma). Whole-rock Nd isotope data show their eNd(t) values in the range of-9.5 to-9.1 and yield paleoproterozoic TDMages(1606–1985 Ma). These characteristics indicate that the JLY A-type granite magma was formed by the partial melting of Meso-Paleoproterozoic crust rocks in the Cathaysia Block. Our study of the JLY A-type granite, together with other Triassic A-type granitesin South China, defines an extensional environment in the late Triassic which probably was caused by the collision of the South China Block with Indochina Block. 展开更多
关键词 A-type granite U-Pb dating Sr-Nd-Hfisotope Late Triassic Fujian Province
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Modelling the Effects of Land-use Change on Runoff and Sediment Yield in the Weicheng River Watershed, Southwest China 被引量:3
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作者 ZHANG Xiao-ke FAN Ji-hui CHENG Gen-wei 《Journal of Mountain Science》 SCIE CSCD 2015年第2期434-445,共12页
As a major sediment area in the upper Yangtze River, Jialing River basin experienced substantial land-use changes, many water conservancy projects were constructed from the 1980 s onward to promote water and soil cons... As a major sediment area in the upper Yangtze River, Jialing River basin experienced substantial land-use changes, many water conservancy projects were constructed from the 1980 s onward to promote water and soil conservation. The water and sediment yield at the watershed outlet was strongly affected by these water conservation works, including ponds and reservoirs, which should be considered in the modelling. In this study, based on the observed data of the Weicheng River catchment, the relationships between precipitation, runoff, vegetation, topography and sediment yield were analyzed, a distributed runoff and sediment yield model(WSTD-SED) was developed, and the hydrological processes of different land-use scenarios were simulated by using the model. The main results are summarized as follows: 1) there is an alternating characteristic in river channels and reservoirs in the Jialing River hilly area, with scour occurring in wet years and deposit occurring in dry years. 2) Most of the sediment deposited in river channels and reservoirs is carried off by the largest flood in the year. 3) The model yielded plausible results for runoff and sediment yield dynamics without the need of calibration, and the WSTD-SED model could be usedto obtain qualitative estimates on the effects of land use change scenarios. 4) The modelling results suggest that a 10% increase in cropland(dry land) reforestation results in a 0.7% decrease in runoff and 1.5% decrease in sediment yield. 展开更多
关键词 Land-use change Hydrological modelling Reforestation scenario Runoff and sediment yield
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Can Artificial Climate Trends in Global Reanalysis be Reduced by Dynamical Downscaling:A Case Study of China 被引量:2
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作者 ZHAO Tian-Bao ZHAO De-Ming 《Atmospheric and Oceanic Science Letters》 2011年第1期30-35,共6页
In this study, the ability of dynamical downscaling for reduction of artificial climate trends in global reanalysis is tested in China. Dynamical downscaling is performed using a 60-km horizontal resolution Regional I... In this study, the ability of dynamical downscaling for reduction of artificial climate trends in global reanalysis is tested in China. Dynamical downscaling is performed using a 60-km horizontal resolution Regional Integrated Environmental Model System (RIEMS) forced by the NCEP-Department of Energy (DOE) reanalysis II (NCEP-2). The results show that this regional climate model (RCM) can not only produce dynamically consis- tent fine scale fields of atmosphere and land surface in the regional domain, but it also has the ability to minimize artificial climate trends existing in the global reanalysis to a certain extent. As compared to the observed 2-meter temperature anomaly averaged across China, our model can simulate the observed inter-annual variation and variability as well as reduce artificial climate trends in the reanalysis by approximately 0.10℃ decade-1 from 1980 to 2007. The RIEMS can effectively reduce artificial trends in global reanalysis for areas in western China, especially for regions with high altitude mountains and deserts, as well as introduce some new spurious changes in other local regions. The model simulations overesti- mated observed winter trends for most areas in eastern China with the exception of the Tibetan Plateau, and it greatly overestimated observed summer trends in the Si- chuan Basin located in southwest China. This implies that the dynamical downscaling of RCM for long-term trends has certain seasonal and regional dependencies due to imperfect physical processes and parameterizations. 展开更多
关键词 dynamical downscaling artificial climate trends global reanalysis
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Status of Soil Zn in Citrus-Cultivated Area of South China
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作者 OUYANG TAOInstitute of Soil Science, A cademia Sinica. P.O. Box 821, Nanjing 210008 (China) 《Pedosphere》 SCIE CAS CSCD 1992年第4期379-382,共4页
INTRODUCTION In recent 10 years,citrus production has developed rapidly in China.The citrus-cul-tivated area of our country is among the largest and its yield occupies the third place inthe world(Shen,1991).However,in... INTRODUCTION In recent 10 years,citrus production has developed rapidly in China.The citrus-cul-tivated area of our country is among the largest and its yield occupies the third place inthe world(Shen,1991).However,in some of our citrus-producing areas the yield is onthe low side and the sugar content of the fruit tends to reduce.The“mosaic”-a physio- 展开更多
关键词 CITRUS soil type zinc effect
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Carbon Emission of Regional Land Use and Its Decomposition Analysis: Case Study of Nanjing City, China 被引量:11
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作者 ZHAO Rongqin HUANG Xianjin +3 位作者 LIU Ying ZHONG Taiyang DING Minglei CHUAI Xiaowei 《Chinese Geographical Science》 SCIE CSCD 2015年第2期198-212,共15页
Through the matching relationship between land use types and carbon emission items, this paper estimated carbon emissions of different land use types in Nanjing City, China and analyzed the influencing factors of carb... Through the matching relationship between land use types and carbon emission items, this paper estimated carbon emissions of different land use types in Nanjing City, China and analyzed the influencing factors of carbon emissions by Logarithmic Mean Divisia Index(LMDI) model. The main conclusions are as follows: 1) Total anthropogenic carbon emission of Nanjing increased from 1.22928 ×10^7 t in 2000 to 3.06939 × 10^7 t in 2009, in which the carbon emission of Inhabitation, mining & manufacturing land accounted for 93% of the total. 2) The average land use carbon emission intensity of Nanjing in 2009 was 46.63 t/ha, in which carbon emission intensity of Inhabitation, mining & manufacturing land was the highest(200.52 t/ha), which was much higher than that of other land use types. 3) The average carbon source intensity in Nanjing was 16 times of the average carbon sink intensity(2.83 t/ha) in 2009, indicating that Nanjing was confronted with serious carbon deficit and huge carbon cycle pressure. 4) Land use area per unit GDP was an inhibitory factor for the increase of carbon emissions, while the other factors were all contributing factors. 5) Carbon emission effect evaluation should be introduced into land use activities to formulate low-carbon land use strategies in regional development. 展开更多
关键词 carbon emission land use intensity Logarithmic Mean Divisia Index(LMDI) model decomposition analysis Nanjing City
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Development of typhoon driven wave nowcasting model in Southeast China Sea 被引量:7
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作者 Zheng Jinhai Feng Xiangbo Yan Yixin 《Engineering Sciences》 EI 2011年第1期2-6,共5页
Using optimal interpolation data assimilation of observed wave spectrum around Northeast coast of Taiwan Island, the typhoon driven wave nowcasting model in Southeast China Sea is setup. The SWAN (simulating waves nea... Using optimal interpolation data assimilation of observed wave spectrum around Northeast coast of Taiwan Island, the typhoon driven wave nowcasting model in Southeast China Sea is setup. The SWAN (simulating waves nearshore) model is used to calculate wave field and the input wind field is the QSCAT/NCEP (Quick Scatterometer/National Centers for Environmental Prediction) data. The two-dimensional wavelet transform is applied to analyze the X-band radar image of nearshore wave field and it reveals that the observed wave spectrum has shoaling characteristics in frequency domain. The reverse calculation approach of wave spectrum in deep water is proposed and validated with experimental tests. The two-dimensional digital low-pass filter is used to obtain the initialization wave field. Wave data during Typhoon Sinlaku is used to calibrate the data assimilation parameters and test the reverse calculation approach. Data assimilation corrects the significant wave height and the low frequency spectra energy evidently at Beishuang Station along Fujian Province coast, where the entire assimilation indexes are positive in verification moments. The nowcasting wave field shows that the present model can obtain more accurate wave predictions for coastal and ocean engineering in Southeast China Sea. 展开更多
关键词 typhoon driven wave nowcasting model data assimilation spectrum reverse calculation
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Projected Changes in Kppen Climate Types in the 21st Century over China 被引量:6
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作者 SHI Ying GAO Xue-Jie WU Jia 《Atmospheric and Oceanic Science Letters》 2012年第6期495-498,共4页
Future changes in the climate regimes over China as measured by the Kppen climate classification are reported in this paper. The analysis is based on a high-resolution climate change simulation conducted by a regional... Future changes in the climate regimes over China as measured by the Kppen climate classification are reported in this paper. The analysis is based on a high-resolution climate change simulation conducted by a regional climate model (the Abdus Salam International Center for Theoretical Physics (ICTP) RegCM3) driven by the global model of Center for Climate System Research (CCSR)/National Institute for Environment Studies (NIES)/Frontier Research Center for Global Change (FRCGC) MIROC3.2_hires (the Model for Interdisciplinary Research on Climate) under the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A1B scenario. Validation of the model performances is presented first. The results show that RegCM3 reproduces the present-day distribution of the Kppen climate types well. Significant changes of the types are found in the future over China, following the simulated warming and precipitation changes. In southern China, the change is characterized by the replacement of subtropical humid (Cr) by subtropical winter-dry (Cw). A pronounced decrease of the cold climate types is found over China, e.g., tundra (Ft) over the Tibetan Plateau and sub-arctic continental (Ec) over northeast China. The changes are usually greater in the end compared with the middle of the 21st century. 展开更多
关键词 climate change regional climate model Kppen climate China
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NUMERICAL STUDY OF INFLUENCE OF THE SSTA IN WESTERN PACIFIC WARM POOL ON RAINFALL IN THE FIRST FLOOD PERIOD IN SOUTH CHINA
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作者 陈艺敏 钱永甫 《Journal of Tropical Meteorology》 SCIE 2005年第1期86-96,共11页
A brief introduction of a global atmospheric circulation model CCM3, which is used to simulate the precipitation in China, the height and the flow fields of the atmosphere, is made and the reliability of simulation is... A brief introduction of a global atmospheric circulation model CCM3, which is used to simulate the precipitation in China, the height and the flow fields of the atmosphere, is made and the reliability of simulation is analyzed. According to the negative correlation between rainfall in the first flood period in South China (FFSC) and sea surface temperature anomalies (SSTA) in a key region in western Pacific warm pool (West Region), two sensitive experiments are designed to investigate the effects of the latter on the former and the possible physical mechanism is discussed. It is found that in cold water (warm water) years, the rainfall in South China (SC) is far more (less) than normal, while the rainfall in the middle and low reaches of the Yangtze River is relatively less (more). The best correlative area of precipitation is located in Guangdong Province. It matches the diagnostic result well. The effect of SSTA on precipitation of FFSC is realized through the abnormality of atmospheric circulation and tested by a P-σnine-layer regional climate model. Moreover, the simulated result of the P-σmodel is basically coincident with that of the CCM3. 展开更多
关键词 CCM3 numerical simulation rainfall in the first flood period in South China SSTA abnormality in western Pacific warm pool P-σnine-layer regional climate model
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Length of stay in urban areas of circular migrants from the mountainous areas in China
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作者 TAN Ming-hong LI Xiu-bin +2 位作者 YAN Jian-zhong XIN Liang-jie SUN Lai-xiang 《Journal of Mountain Science》 SCIE CSCD 2016年第5期947-956,共10页
Currently, there is limited literature dealing with the length of stay of circular migrants in urban areas (LSCMU), although many studies have discussed the phenomenon of migration and the determinants of migration.... Currently, there is limited literature dealing with the length of stay of circular migrants in urban areas (LSCMU), although many studies have discussed the phenomenon of migration and the determinants of migration. This study attempts to fill that gap using survey data from the mountainous areas of Chongqing, Southwest China. From a comparative perspective, this study divided workers into two groups (a young group aged between 16 and 35 years and an old group aged between 36 and 65 years). The average LSCMU values for the young and old groups were 225 days and ~74 days, respectively. Two multi-regression models were used to estimate the determinants of LSCMU in the two groups. The results showed that LSCMU was closely related to individual factors in both groups, including gender, age and job training. Family and community factors, including household size, arable land per capita and the distance from market, had much weaker effects on the dependent variable, especially in the older group. It was noticeable that job training had significant positive effects on LSCMU in both groups; these findings have special implications for the urbanization process in China. 展开更多
关键词 Circular migrants URBAN Mountain areas China
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SAR Image Coregistration Using Fringe Definition Detection
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作者 YANG Ying-hui CHEN Qiang +3 位作者 LIU Guo-xiang Li Zhi-lin CHENG Hai-qin Liu Li-yao 《Journal of Mountain Science》 SCIE CSCD 2013年第5期790-800,共11页
In order to overcome the limitation of cross correlation coregistration method for Synthetic Aperture Radar (SAR) interferometric pairs with low coherence, a new image coregistration algorithm based on Fringe Defini... In order to overcome the limitation of cross correlation coregistration method for Synthetic Aperture Radar (SAR) interferometric pairs with low coherence, a new image coregistration algorithm based on Fringe Definition Detection (FDD) is presented in this paper. The Fourier transformation was utilized to obtain spectrum characteristics of interferometric fringes. The ratio between spectrum mean and peak was proposed as the evaluation index for identifying homologous pixels from interferometric images. The satellites ERS-1/2 C-band SAR acquisitions covering the Yangtze River plain delta, eastern China and ALOS/PALSAR L-band images over the Longmen Shan mountainous area, southwestern China were respectively employed in the experiment to validate the proposed coregistration method. The testing results suggested that the derived Digital Elevation Model (DEM) from FDD method had good agreement with that from the cross correlation method as well as the reference DEM at high coherence area. However, The FDD method achieved a totally improved topographic mapping accuracy by 24 percent in comparison to the cross correlation method. The FDD method also showed better robustness and achieved relatively higher performance for SAR image eoregistration in mountainous areas with low coherence. 展开更多
关键词 SAR image coregistration Spectrumcharacteristics Fringe definition detection Interferometric Synthetic Aperture Radar (InSAR) Accuracy assessment
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