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Distribution dataset of 1:250000 residential areas in Qinghai lake basin (2000)

Qinghai Lake is the largest inland salt water lake in China, which is located in the northeast of Qinghai Tibet Plateau. Its unique natural ecological environment and biodiversity are of great significance in the western development and ecological construction. The data is the distribution data of residential areas in the Qinghai Lake Basin, including the distribution of cities, counties, towns and villages in the Qaidam River Basin. The data mainly has two attribute fields: Code (residential area code) and name (residential area name). Collect and sort out the basic, meteorological, topographical and geomorphological data of Qinghai Lake Basin, and provide data support for ecological management of Qinghai Lake Basin.

2020-03-30

1:250000 administrative boundary distribution dataset Shule river basin (2000)

Shule River Basin is one of the three inland river basins in Hexi corridor. In recent years, with the obvious change of climate and the aggravation of human activities, the shortage of water resources and the problem of ecological environment in Shule River Basin have become increasingly prominent. It is of great significance to study the runoff change of Shule River Basin in the future climate situation for making rational water resources planning and ecological environment protection. The data set is the administrative boundary vector map of Shule River Basin, with a scale of 250000. The data includes spatial data and attribute data. The attribute fields are name (county boundary name) and code (administrative code). Collect and sort out the basic, meteorological, topographical and geomorphic data of Shule River Basin, and provide data support for the management of Shule River Basin.

2020-03-30

Reanalysis data for surface meteorological elements for western China (2002)

The research project on land surface data assimilation system in western China belongs to the major research plan of "environment and ecological science in western China" of the national natural science foundation. the person in charge is Li Xin, researcher of the institute of environment and engineering in cold and arid regions of the Chinese academy of sciences. the project runs from January 2003 to December 2005. One of the data collected in this project is the reanalysis data of surface climate factors in western China in 2002. This data set is generated based on the daily 1 × 1 provided by the National Environmental Prediction Center (NCEP). However, the re-analysis of the data has the following problems: (1) the temporal and spatial resolution is not high enough (the horizontal resolution is 1 degree and the time is 6 hours); (2) The low-level errors in plateau areas are large; (3) The data are standard isosurface data and need interpolation. The 2002 reanalysis data set of surface climate elements in western China was generated by combining NCEP reanalysis data and MM5 model by Dr. Longxiao and Professor Qiu Chongjian of Lanzhou University using Newton relaxation data assimilation method (Nudging), including 10m horizontal and vertical wind speed (m/s), 2m air temperature (k), 2m mixing ratio, surface pressure (Pa), upstream and downstream short wave and long wave radiation (w/m2), convective precipitation and large scale precipitation (mm/s) at 0.25 degree per hour throughout 2002. I. preparation background The quality of the driving data seriously affects the ability of the land surface model to simulate the land surface state, so a very important component of the land surface modeling research is the driving data used to drive the land surface model. No matter how realistic these models are in describing the surface process, no matter how accurate the boundary and initial conditions they input, if the driving data are not accurate, they cannot get the results close to reality. Land surface models are so dependent on the quality of externally provided data that any error in these externally provided data will seriously affect the ability of land surface models to simulate soil moisture, runoff, snow cover and latent heat flux. These externally provided data include: precipitation, radiation, temperature, wind field, humidity and pressure. The 2002 reanalysis data set of surface climate elements in western China uses Newton relaxation data assimilation method (Nudging) to combine NCEP reanalysis data and MM5 model to generate driving data with higher spatial and temporal resolution suitable for complex terrain in western China. Second, the basic parameters of the operation mode 1. Using the US PSU/NCAR mesoscale model MM5 as a simulation model; The selection of simulation grid domain: center (32°N, 90°E), grid distance of 36km, number of horizontal grid points of 131*151, vertical resolution of 25 layers, and mode top of 100hPa;; 2. The data used for initialization are 1 * 1 GRIB grid data of NCEP in the United States. 3. The time step is 120s. Third, the physical process 1. physical process treatment of cloud and precipitation: Grell cumulus cloud parameterization scheme is adopted for sub-grid scale precipitation, and Reisner mixed phase microphysical explicit scheme is adopted for distinguishable scale precipitation; 2. MRF parameterization scheme is adopted for planetary boundary layer process. 3. the radiation process adopts CCM2 radiation scheme. IV. File Format and Naming It is stored in a monthly folder and contains 24 hours of data every day. The naming rules are as follows: 2002***&.forc, where * * * is Julian day and 2002***& is time (in hours), where. forc is the file extension. V. data format Stored in binary floating point type, each data takes up 4 bytes.

2020-03-29

1:100,000 desert (sand) distribution dataset in China

This dataset is the first 1: 100,000 desert spatial database in China based on the graphic data of desert thematic maps. It mainly reflects the geographical distribution, area size, and mobility of sand dunes in China. According to the system design requirements and relevant standards, the input data is standardized and uniformly converted into a standard format for various types of data input. Build a library to run the delivery system. This project uses the TM image in 2000 as the information source, and interprets, extracts, and edits the coverage of the national land use map and TM digital image information in 2000. It uses remote sensing and geographic information system technology to 1: 100,000 Thematic mapping requirements for scale bar maps were made on the desert, sandy land and gravel Gobi in China. The 1: 100,000 desert map across the country can save users a lot of data entry and editing work when they are engaged in research on resources and the environment. Digital maps can be easily converted into layout maps The dataset properties are as follows: Divided into two folders e00 and shp: Desert map name and province comparison table in each folder 01 Ahsm Anhui 02 Bjsm Beijing 03 Fjsm Fujian 04 Gdsm Guangdong 05 Gssm Gansu 06 Gxsm Guangxi Zhuang Autonomous Region 07 Gzsm Guizhou 08 Hebsm Hebei 09 Hensm Henan 10 Hljsm Heilongjiang 11 Hndsm Hainan 12 Hubsm Hubei 13 Jlsm Jilin Province 14 Jssm Jiangsu 15 Jxsm Jiangxi 16 Lnsm Liaoning 17 Nmsm Inner Mongolia Gu Autonomous Region 18 Nxsm Ningxia Hui Autonomous Region 19 Qhsm Qinghai 20 Scsm Sichuan 21 Sdsm Shandong 22 Sxsm Shaanxi Province 23 Tjsm Tianjin 24 Twsm Taiwan Province 25 Xjsm Xinjiang Uygur Autonomous Region 26 Xzsm Tibet Autonomous Region 27 Zjsm Zhejiang 28 Shxsm Shanxi 1. Data projection:                Projection: Albers                False_Easting: 0.000000                False_Northing: 0.000000                Central_Meridian: 105.000000                Standard_Parallel_1: 25.000000                Standard_Parallel_2: 47.000000                Latitude_Of_Origin: 0.000000                Linear Unit: Meter (1.000000) 2. Data attribute table: area (area)                   perimeter                   ashm_ (sequence code)                   class (desert encoding)                   ashm_id (desert encoding) 3. Desert coding: mobile sandy land 2341010                   Semi-mobile sandy land                   Semi-fixed sandy land 2341030                   Gobi 2342000                   Saline land 2343000 4: File format: National, sub-provincial and county-level desert map data types are vector shapefiles and E00 5: File naming: Data organization based on the National Basic Resources and Environmental Remote Sensing Dynamic Information Service System is performed on the file management layer of Windows NT. The file and directory names are compound names of English characters and numbers. Pinyin + SM composition, such as the desert map of Gansu Province is GSSM. The flag and county desert map is the pinyin + xxxx of the province name, and xxxx is the last four digits of the flag and county code. The division of provinces, districts, flags and counties is based on the administrative division data files in the national basic resources and environmental remote sensing dynamic information service operation system.

2020-03-29

1:250000 residential area distribution data set of Shule river basin (2000)

Shule River Basin is one of the three inland river basins in Hexi corridor. In recent years, with the obvious change of climate and the aggravation of human activities, the shortage of water resources and the problem of ecological environment in Shule River Basin have become increasingly prominent. It is of great significance to study the runoff change of Shule River Basin in the future climate situation for making rational water resources planning and ecological environment protection The data is residential area distribution data of Shule River Basin, including city, county, town and village level distribution in Shule River Basin. The data mainly has two attribute fields: Code (residential area code) and name (residential area name) Collect and sort out the basic, meteorological, topographical and geomorphic data of Shule River Basin, and provide data support for the management of Shule River Basin.

2020-03-29

1:250000 road distribution dataset of Shule river basin (2000)

Shule River Basin is one of the three inland river basins in Hexi corridor. In recent years, with the obvious change of climate and the aggravation of human activities, the shortage of water resources and the problem of ecological environment in Shule River Basin have become increasingly prominent. It is of great significance to study the runoff change of Shule River Basin in the future climate situation for making rational water resources planning and ecological environment protection. The data is the road distribution data set of Shule River Basin, scale: 250000, including the spatial distribution and attribute data of main level roads in Shule River Basin, attribute fields: Code (road code), name (road classification) Collect and sort out the basic, meteorological, topographical and geomorphic data of Shule River Basin, and provide data support for the management of Shule River Basin.

2020-03-29

1:250000 railway distribution dataset of Shule river basin (2000)

Shule River Basin is one of the three inland river basins in Hexi corridor. In recent years, with the obvious change of climate and the aggravation of human activities, the shortage of water resources and the problem of ecological environment in Shule River Basin have become increasingly prominent. It is of great significance to study the runoff change of Shule River Basin in the future climate situation for making rational water resources planning and ecological environment protection. The data is the spatial distribution of railway in Shule River Basin, with scale of 250000 and projection longitude and latitude. The data includes spatial data and attribute data. Attribute field: Code (railway code). Collect and sort out the basic, meteorological, topographical and geomorphic data of Shule River Basin, and provide data support for the management of Shule River Basin.

2020-03-29

Elevation dataset of ASTER_DEM in the Yellow river upstream (2009)

Ⅰ. Overview This dataset is derived from the global 30m-resolution digital elevation product dataset, which is processed using the data of the first version (v1) of ASTER GDEM. Its spatial resolution is 30m. Due to the influence of clouds, lines, pits, bulges, dams or other anomalies generated by the boundary stacking, there are local anomalies in the first version of the original data of ASTER GDEM, so the digital elevation processed by ASTER GDEM v1 Data products have data anomalies in individual areas, and users need to pay attention to them during use. In addition, this data set can complement the SRTM global 90m resolution elevation dataset. Ⅱ. Data processing description ASTER GDEM is a fully automated method to process and generate ASTER archived data of 1.5 million scenes, including 1,264,118 ASTER DEM data based on independent scenes generated through stereo correlation. After de-cloud processing, residual outliers are removed, and the average value is taken as the final pixel value of ASTER GDEM object area. After correcting the remaining abnormal data, the global ASTER GDEM data was generated by 1°× 1° sharding. Ⅲ. Data content description The dataset covers the entire upper reaches of the Yellow River, and each data file name is generated based on the latitude and longitude of the lower left (southwest) Angle of the fractal geometry center. For example, the lower-left coordinate of the ASTGTM_N40E116 file is 40 degrees north latitude and 116 degrees east longitude. ASTGTM_N40E116_dem and ASTGTM_N40E116_num correspond to digital elevation model (DEM) and quality control (QA) data, respectively. Ⅳ. Data usage description ASTER GDEM data can be calculated and visualized. It has a broad application prospect in various fields, especially in mapping, surface deformation and military fields.Specifically, it mainly includes the following aspects: In scientific research, ASTER GDEM data plays an important role in geology, geophysics, seismic research, horizontal modeling, volcano monitoring and remote sensing image registration.The three-dimensional model of the ground is built by using high-precision digital terrain elevation data, which can be embedded and superimposed with the image of the ground to observe subtle changes of the earth surface. In civil and industrial applications, ASTER GDEM data can be used for civil engineering calculation, dam site selection, land use planning, etc. In communications, digital topographic data can help businesses build better broadcast towers and determine the best location of mobile phone booths.In terms of aviation safety, ASTER GDEM digital elevation data can be used to establish the enhanced aircraft landing alarm system, which greatly improves the aircraft landing safety coefficient. In the military, ASTER GDEM data is the basic information platform of C4ISR (army automatic command system), which is indispensable in the study of battlefield regional structure, combat direction, battlefield preset, combat deployment, troop concentration in projection, protection conditions, logistics support and other aspects.

2020-03-29

Digital elevation model of SRTM in the Yellow river upstream (2000)

Ⅰ. Overview The SRTM (Space Shuttle Radar Topographic Mapping Mission) was performed by NASA, the Geospatial Intelligence Agency, and German and Italian space agencies in February 2002. A total of 222 hours and 23 minutes of data collection was performed by the US space shuttle Endeavour onboard the SRTM system, and 9.8 trillion bytes of radar images were collected between 60 degrees in North America and 56 degrees in south latitude with an area of ​​more than 119 million km2 Data, Fei changed more than 80% of the earth's surface, this data set covers the entire territory of China. It took two years to process, and finally obtained a global digital elevation model (DEM) with a plane longitude of ± 20m and an elevation longitude of ± 16m. Ⅱ. Data processing description The processing of SRTM data is done by the Ground Data Processing System (GDPS). The GDPS consists of three parts: (1) an interferometric processor, which uses the interferometric processor to convert the data into elevation maps and radar image bands; (2) a mosaic processor, which is used to compile collected global airborne data Draw a mosaic map of continental elevation data and images; (3) Verification system is responsible for checking the quality of the mosaic map and providing accuracy maps. These processors are currently installed on JPL workstations, and the next step is to install them on a set of supercomputers for the systematic processing of real SRTM data. As this work progresses, JPL will release auxiliary data to the work. Ⅲ. Data content description SRTM data provides a file for each latitude and longitude grid. There are two types of longitude: 1 arc-second and 3 arc-second. Called SRTM1 and SRTM3, or 30m and 90m data. This dataset uses SRTM3 data with 90m resolution. Each file contains elevation data of 1201 × 1201 sampling points. The data format is DEM format. The spatial position of each picture frame is shown in the attached picture (1-25 thousand pictures in the country). Ⅳ. Data usage description SRTM data has computable and visual functions, and has broad application prospects in various fields, especially in the fields of surveying and mapping, surface deformation, and military. Specifically, it mainly includes the following aspects: In scientific research, SRTM data plays a very important role in geology, geophysics, seismic research, level modeling, volcano monitoring, and registration of remote sensing images. Using high-precision digital terrain elevation data to build a three-dimensional three-dimensional model of the ground, which is superimposed on the ground image, can observe slight changes in the earth's surface. In civil and industrial applications, SRTM data can be used for civil engineering calculations, reservoir dam site selection, land use planning, etc. In terms of communications, digital terrain data can help businesses build better broadcast towers and determine the best In terms of aviation safety, the use of SRTM digital elevation data can establish an enhanced aircraft landing alarm system, which greatly improves the aircraft landing safety factor. In the military, SRTM data is the basic information platform of C4ISR (Army Automatic Command System). It is necessary to study the structure of the battlefield, the direction of the battlefield, the presetting of the battlefield, the deployment of operations, the concentration of forces in the delivery, the protection conditions, and logistics support Essential.

2020-03-29

Digital elevation model of the Heihe river basin (2013-2016)

Adopt aster with 30 meter resolution provided by Heihe project data management center GDEM data and 90 meter resolution SRTM data are two sets of grid data, as well as multi-source point data. These point data include radar point cloud elevation data in the middle and upper reaches; elevation data extracted from soil sample points and vegetation sample in the data management center of Heihe plan; elevation data extracted from climate and hydrological stations; and elevation sample data measured by the research group. By using the HASM scaling up algorithm, the grid data of different sources and different precision are fused with the elevation point data to obtain the high-precision DEM data of Heihe River Basin. First of all, the accuracy of two groups of grid data is verified by using various point data. According to the results of accuracy verification, different grid data are used as the trend surface of data fusion in different regions. The residuals of various point data and trend surface are calculated, and the residual surface is obtained by interpolation with HASM algorithm, and the trend surface and residual surface are superposed to obtain the final DEM surface. The spatial resolution is 500 meters.

2020-03-28