Eearth最新文献_第3页

The Progress of Dry–wet Climate Divisional Research in China 中国干湿气候区划研究进展

Eearth Pub Date : 2020-01-04 DOI: 10.11648/J.EARTH.20200901.12

Cunjie Zhang, Yaoming Liao, Yanling Song

{"title":"The Progress of Dry–wet Climate Divisional Research in China","authors":"Cunjie Zhang, Yaoming Liao, Yanling Song","doi":"10.11648/J.EARTH.20200901.12","DOIUrl":"https://doi.org/10.11648/J.EARTH.20200901.12","url":null,"abstract":"The dry–wet climate regionalization index, potential evapotranspiration calculation methods, standard and named methods of dry–wet climate regionalization, etc., since the middle of the 20th century are reviewed in this paper. Using the arid index, climate regionalization and class standards were given on the basis of former review. Then, the characteristics of wet–dry climate division were analyzed using observed data at 2207 national meteorological stations from 1981 to 2010. The results showed that the total arid area (including extreme arid, arid and semi-arid areas) was 4.692 million hm2 in China, accounting for 48.8% of the land area in China, which included 878,000 hm2 (9.1%), 2.092 million hm2 (21.8%) and 1.722 million hm2 (17.9%) for extreme arid, arid and semi-arid area, respectively. The arid areas were mainly distributed in Xinjiang, Inner Mongolia, Tibet, Qinghai, Gansu and other western regions. Sub-humid area, wet area and excessive wet area accounted for 1.6%, 27.8% and 8.8% of China’s land area, respectively, mainly located in the south of the Yangtze River and Northeast China. Since 1961, the overall characteristics of dry-wet climate change in China are that the total arid areas shows a decreasing trend, while the total wet areas shows an increasing trend.","PeriodicalId":350455,"journal":{"name":"Eearth","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116064179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Wind Farms and Climate Change in Eurasia and America 欧亚大陆和美洲的风力发电场与气候变化

Eearth Pub Date : 2020-01-04 DOI: 10.11648/J.EARTH.20200901.11

S. I. Gordeev, Victoria Nikolaevna Voloshina

引用次数: 0

Petro-Structural Characterization of Bonguen Area, Nyong Series, Cameroon: Insight into the Northern Extension of Kribi-Campo Shear Zone 喀麦隆Nyong系列Bonguen地区油气构造特征——以Kribi-Campo剪切带北延为例

Eearth Pub Date : 2018-10-24 DOI: 10.11648/J.EARTH.20180705.15

Kouankap Nono Gus Djibril, N. Laure, Takodjou Wambo Jonas Didero, Kamguia Woguia Brice, Afahnwie Ngambu Aloysius, F. Hermann, Folah Mewa Cathy Laurianne

{"title":"Petro-Structural Characterization of Bonguen Area, Nyong Series, Cameroon: Insight into the Northern Extension of Kribi-Campo Shear Zone","authors":"Kouankap Nono Gus Djibril, N. Laure, Takodjou Wambo Jonas Didero, Kamguia Woguia Brice, Afahnwie Ngambu Aloysius, F. Hermann, Folah Mewa Cathy Laurianne","doi":"10.11648/J.EARTH.20180705.15","DOIUrl":"https://doi.org/10.11648/J.EARTH.20180705.15","url":null,"abstract":"The west Bonguen area is located within latitudes 03°25’N to N03°39’N and longitudes 10°04’E to 10°09’ E in South Cameroon. It belongs to the Nyong Series which is the north-western extension of the Congo Craton in Cameroon. In order to highlight the extension of the Kribi-Campo shear zone, petrographic studies and structural analysis were carried out. Mylonitic metagranodiorite outcropping as a large dome in biotite gneiss basement rocks, it is the main rock type in the study area, it is made up of Kfs + Qtz + Bt + Pl + Op. Majority of the minerals shows deformation marks such as sigmoidal shape of Kfs, rolling extension of Qtz ribbons, Subgrains of Qtz and kink-band of Bt. Three (03) deformation phases (D1, D2, and D3) were denoted in Bonguen west. The D1 deformation developed S1 foliation in biotite gneiss basement rocks and is characterized by the alternation of parallel compositional bands and lithological units. The D2 deformation developed S2 mylonitic shistosity, Shear bands (C2-planes) develop oblique to the main S2 mylonitic schistosity (S2-plane) showing dextral ductile shear, V2 veins and B2 boudins. The D3 phase is exclusively highlighted by brittle features such as V3 veins, F3 joints and faults. The area consequently underwent a polyphases ductilo-fragile tectonism dominated by a dextral thrusting kinematics. Bonguen area is here considered as a segment of the northern extension of the Kribi-Campo fault.","PeriodicalId":350455,"journal":{"name":"Eearth","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130408914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration 植被指数法估算实际蒸散量的精度评价

Eearth Pub Date : 2018-10-11 DOI: 10.11648/J.EARTH.20180705.14

Arturo Reyes-González, J. Kjaersgaard, T. Trooien, C. Hay, L. Ahiablame

{"title":"Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration","authors":"Arturo Reyes-González, J. Kjaersgaard, T. Trooien, C. Hay, L. Ahiablame","doi":"10.11648/J.EARTH.20180705.14","DOIUrl":"https://doi.org/10.11648/J.EARTH.20180705.14","url":null,"abstract":"The estimation of actual crop evapotranspiration (ET a ) maps using complex equations and remotely sensed shortwave and thermal infrared imagery can be challenging and may require input data that are not available. There is an opportunity, therefore to create a simpler and faster method to generate ET a maps using fewer input parameters for situations where limited input data is available or greater uncertainty in the resulting ET estimates are acceptable. We compared the estimates of ET a produced by a crop coefficient and NDVI-based (K c-NDVI ) method to a full energy balance (EB) method. Clear sky images from Landsat 7 and Landsat 8 were processed and used for the ET a estimations from maize during two growing seasons in eastern South Dakota, USA. The results showed that the ET a values from the K c-NDVI method were lower than the ET a values from the EB method by 18% for 2015 and 11% for 2016 growing season. During study period the accuracy of ET a estimation decreased 17% with the K c-NDVI method. For both years the mean bias error was 0.81 mm day -1 and the root mean square error (RMSE) was 0.37 mm day -1 . The average daily ET a of 5.3 mm day -1 . The K c-NDVI method performed acceptable for ET a estimations, indicating that this method can be used to estimate ET a with minimum input parameters at focused regional and field scales for short time periods.","PeriodicalId":350455,"journal":{"name":"Eearth","volume":"12 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123681337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Coupled Flow Simulation and Geomechanical Modeling on CO 2 Storage in a Saline Aquifer 含盐含水层CO 2储存的耦合流动模拟与地质力学模拟

Eearth Pub Date : 2018-09-28 DOI: 10.11648/J.EARTH.20180705.13

L. Ji

{"title":"Coupled Flow Simulation and Geomechanical Modeling on CO 2 Storage in a Saline Aquifer","authors":"L. Ji","doi":"10.11648/J.EARTH.20180705.13","DOIUrl":"https://doi.org/10.11648/J.EARTH.20180705.13","url":null,"abstract":"As an option to mitigate the increasing level of greenhouse gas emission, a number of Carbon Capture and Storage (CCS) testing and pilot projects have been brought up all over the world. In general, there are three types of CO 2 storage formations, such as deep saline aquifers, depleted oil and gas reservoirs, and un-mineable coal seams. This study is focused on the deep saline aquifer which has the largest potential for CO 2 storage. There are a lot of uncertainties associated with this type of storage, such as storage capacity, geomechanical properties, and sealing behaviour of the caprock. Pressure (and temperature) changes during CO 2 injection and storage can have significant impact on the stress and strain field and may cause relevant geomechanical problems. This paper shows a case study of a synthetic saline aquifer storage site, where a 15-year injection at a rate of 15 MT/year was simulated. Sealing performance and leakage risk were evaluated. A number of sensitivity studies were conducted to analyse the impacts of different rock properties on CO 2 leakage potentials. Coupled flow simulation and geomechanical modeling was performed to monitor stress-strain evolutions and to predict failure potentials in response to pressure changes during CO 2 injection and storage. The findings show that CO 2 leakage is most sensitive to caprock permeability. Other factors such as reservoir properties, boundary conditions, and perforation intervals also have certain degree of influence on the leakage. During the 15-year injection, there is no significant risk of potential failure; however, this may happen in local area due to formation heterogeneity.","PeriodicalId":350455,"journal":{"name":"Eearth","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116043623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

The Traditional Knowledge Associated to Biodiversity in an Age of Climate Change 气候变化时代与生物多样性相关的传统知识

Eearth Pub Date : 2018-09-15 DOI: 10.11648/J.EARTH.20180705.12

L. Yin, M. Zachary, Yanyan Zheng

{"title":"The Traditional Knowledge Associated to Biodiversity in an Age of Climate Change","authors":"L. Yin, M. Zachary, Yanyan Zheng","doi":"10.11648/J.EARTH.20180705.12","DOIUrl":"https://doi.org/10.11648/J.EARTH.20180705.12","url":null,"abstract":"Climate change has largely influenced the biodiversity in the world, as the biodiversity hotspots areas are often also rich in cultural diversity, the local peoples have rich traditional knowledge associated to biodiversity, and these knowledge also provide alternative information about climate variability and climate change based on the experience and practices of biodiversity resource use. This review work examines the researches about traditional knowledge associated to biodiversity in monitoring and adapting to changing climatic conditions in different parts of the globe. We reviewed different reports from both International and Regional Organizations whereby we based our findings from the traditional knowledge and climate change, the traditional knowledge’s perception and lastly traditional knowledge’s adaption to climate change. In our findings we realized that traditional knowledge associated to biodiversity is not only effective toolbox, but also a process to adopt to the climate change at local level. Lastly this review also demonstrates how local people use their traditional knowledge about the climate to guide their biodiversity resource and its management. The disasters arising from negative impacts of climate change has brought many risks and threats to the indigenous peoples. This paper highlights the importance of integrating the scientific models in conjunction with traditional knowledge system of indigenous peoples. Integrating this traditional knowledge can add a significance value to the development of sustainable climate change mitigation and adaptation strategies that are rich in local content. It was observed that the traditional knowledge and coping strategies can no longer be fully adapted to the intensity and frequency of the present climate change due to unlimited resources and also lack the enough support from both local and international communities’ responsible for the climate policies.","PeriodicalId":350455,"journal":{"name":"Eearth","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126577863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Impact of Tailings on Surrounding Streams at a Mining Area in Sierra Leone 塞拉利昂某矿区尾矿对周围溪流的影响

Eearth Pub Date : 2018-09-06 DOI: 10.11648/j.earth.20180705.11

Ishmail Sheriff, E. T. Taylor, Alusine Kamara, A. Sannoh

{"title":"Impact of Tailings on Surrounding Streams at a Mining Area in Sierra Leone","authors":"Ishmail Sheriff, E. T. Taylor, Alusine Kamara, A. Sannoh","doi":"10.11648/j.earth.20180705.11","DOIUrl":"https://doi.org/10.11648/j.earth.20180705.11","url":null,"abstract":"Access to clean water and sanitation is the centerpiece of Africa water vision 2025 and Goal six (6) of the 2030 UN agenda for Sustainable Development. Considering the current national WASH regulatory structures in Sierra Leone, meeting these targets enshrined in the policy documents would be a critical challenge for the government. The overarching objectives sought by the study were to determine the available composition of physio-chemical parameters and evaluate impact of mine tailings on nearby water bodies within the operational areas of Sierra Rutile Mining Company Limited. Twenty-four (24) water samples obtained from six (6) streams were tested for seventeen (17) physical and chemical parameters. About 30% of the indicators were noted to be above the permissible limit of water quality standard in almost all of the sampling sites. A pattern of decrease concentration downstream for Zn, Pb and Cu was observed but those at the tailing points were noted otherwise. The results revealed that mining activities have to an extent negative impact on the local water sources. Consequently, certain indicators were considered to be of public health concern considering their baseline levels. It would be necessary for the company to examine the mechanism of discharge of tailings and strengthen the environmental surveillance within its concessionary areas to enhance sustainability with the ultimate goal to improve environmental performance.","PeriodicalId":350455,"journal":{"name":"Eearth","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122745269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Predicting of the Seismogram and Accelerogram of Strong Motions of the Soil for an Earthquake Model Considered as an Instantaneous Rupture of the Earth’s Surface 考虑地表瞬时破裂的地震模型的地震记录和土壤强运动加速度的预测

Eearth Pub Date : 2018-08-30 DOI: 10.11648/J.EARTH.20180704.16

E. Khachiyan

{"title":"Predicting of the Seismogram and Accelerogram of Strong Motions of the Soil for an Earthquake Model Considered as an Instantaneous Rupture of the Earth’s Surface","authors":"E. Khachiyan","doi":"10.11648/J.EARTH.20180704.16","DOIUrl":"https://doi.org/10.11648/J.EARTH.20180704.16","url":null,"abstract":"Problems of the prediction of displacement and acceleration values for strong soil displacements are considered for the case where an earthquake is regarded as an instantaneous mechanical rupture of the Earth’s surface. We have attempted to develop, based on recent concepts of earthquake generation process, simplified theoretical methods for the quantitative prediction of soil displacement parameters during strong earthquakes. As an illustrative example, we consider an earthquake originating as a consequence of relative displacements of suddenly ruptured blocks in a horizontal direction with a given initial velocity. An empirical relationship between soil particle motion velocity near the rupture and at a certain distance from it, on one hand, and the earthquake magnitude, on the other hand, was established. It is assumed that the impact of inertial motions of a deep soil stratum on the inertial motions of upper subsurface soil stratum at instantaneous break of a medium can be neglected. By solving a wave problem for a multilayer near surface stratum, analytical relations were developed for a soil seismogram and accelerogram on the surface depending on the physical–mechanical and dynamic characteristics of the soil at all layers of the stratum; attenuation coefficients of mechanical soil vibrations; the distance to the rupture; and the magnitude of the predicted earthquake. The results obtained enable us to determine the maximum displacement and acceleration values of the soil, taking into account local soil conditions and their variations over time, as well as the values of the predominant vibration periods in the soil. The method was applied for solid and loose soil basements.","PeriodicalId":350455,"journal":{"name":"Eearth","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128136072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Characteristics of Convective Storm Top Altitudes in Summer over the Tibetan Plateau by GPM 青藏高原夏季对流风暴顶高度的GPM特征

Eearth Pub Date : 2018-08-29 DOI: 10.11648/J.EARTH.20180704.15

Cai Hong-ke, S. Yi, Chen Quan-liang

{"title":"Characteristics of Convective Storm Top Altitudes in Summer over the Tibetan Plateau by GPM","authors":"Cai Hong-ke, S. Yi, Chen Quan-liang","doi":"10.11648/J.EARTH.20180704.15","DOIUrl":"https://doi.org/10.11648/J.EARTH.20180704.15","url":null,"abstract":"To have a clear understanding of the convective precipitation over the Tibetan Plateau (TP) and its surrounding regions, this research systematically studied characteristics of distribution of convective storm top altitudes over the Tibetan Plateau and its surrounding regions by using the level-2 orbital data obtained by the Global Precipitation Mission (GPM) Dual-frequency Precipitation Radar (DPR). The following conclusions are drawn in this study. (1) Because of the development of Asia summer monsoon, the number of samples of precipitation with storm top altitude above 10 km increases gradually from June to August, and all the samples of precipitation diminishes with the increases of altitude. That is, the higher the storm top altitude, the less the frequency of precipitation. (2) The deep convection frequency above 10 km altitude over the Tibetan Plateau and its surrounding regions is less than 0.8%. The deep convection frequency above 14 km is obviously less than the 10 km deep convection, not exceeding 0.2%. (3) With the increase of convective storm top altitude, the proportion of corresponding deep convection decreases exponentially. The contribution of convective precipitation to total precipitation is consistent with the contribution of convective precipitation frequency to total precipitation frequency, and the both area fractions of them decrease rapidly with the increases of the contribution. Besides, both of the two maximum contributions are below 40%. (4) The storm top altitude and surface rain rate of convective precipitation are the lowest in June and the highest in August. Furthermore, the storm top altitude over the TP rises slowly from the western part of the plateau to the eastern part, and the rain rate shows a significant gradient change with the increases of height. Below 6 km altitude, the maximum value of rain rate can reach 8 mm/h, but the precipitation intensity reduce to 4 mm/h when the altitude is above 6 km.","PeriodicalId":350455,"journal":{"name":"Eearth","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127524114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical Simulation of Diagenetic Stage in Sandstone Reservoir of Huagang Formation in Xihu Sag 西湖凹陷华岗组砂岩储层成岩阶段数值模拟

Eearth Pub Date : 2018-07-27 DOI: 10.11648/J.EARTH.20180704.14

X. Min, Y. Taiju, Q. Wendao, Zhang Chang-min, H. Guowei, H. Miao

引用次数: 0