SRTM 90米分辨率高程数据来源于NASA，数据时间为2000年，SRTM数据采用WGS84椭球投影，经过本单位工作人员对原始下载数据的预处理和处理，得到中亚五国90米DEM数据集（srtm90m_ca），数据的海拔数值为-227-7050米之间，空数据用-32768表示，DEM数据格式为IMG栅格影像，水平精度20米，高程精度16米，数据范围为东经45°-108°，北纬32°-56°。
", "ds_source": "SRTM（ShuttleRadarTopographyMission）30米分辨率高程数据由美国太空总署（NASA）和国防部国家测绘局（NIMA）联合测量。SRTM系统获取的雷达影像的数据量约为9.8万亿字节，经过两年多的数据处理，制成了数字地形高程模型（DEM），即现在的SRTM3地形产品数据。
", "ds_process_way": "预处理：利用Arcmap10.2软件打开DEM高程数据，经过栅格计算和再分类计算得到正常海拔值（-227-7050米）的DEM数据，经由中亚五国边界裁剪，得到该数据。\nDEM渲染图处理：由预处理后的DEM数据分别生成山体阴影数据（Zfactor=5），山体阴影数据与DEM数据叠加生成DEM渲染图。该渲染图可由用户根据自身需要再加工处理。
", "ds_quality": "所有处理过程均未对数据进行破坏，完整保留了原始数据的属性信息。渲染图的生产只是让用户看清数据的精细程度，没有添加其他要素。本数据分辨率为90米，可以和30米分辨率数字高程数据产品互相补充使用。
", "ds_acq_start_time": null, "ds_acq_end_time": null, "ds_acq_place": "", "ds_acq_lon_east": null, "ds_acq_lat_south": null, "ds_acq_lon_west": null, "ds_acq_lat_north": null, "ds_acq_alt_low": null, "ds_acq_alt_high": null, "ds_share_type": "login-access", "ds_total_size": 1004956141, "ds_files_count": 1, "ds_format": ".fgdbr格式", "ds_space_res": "90", "ds_time_res": "无", "ds_coordinate": "WGS84", "ds_projection": "WGS84", "ds_thumbnail": "e1c7fe4c-29d0-48d0-9fcb-d2ed66230c7e.jpg", "ds_thumb_from": 2, "ds_ref_way": "", "paper_ref_way": "", "ds_ref_instruction": "", "ds_from_station": null, "organization_id": "a5877b42-96ea-4f13-af7e-246f355413d6", "doi_value": "", "subject_codes": [ "170.40" ], "quality_level": 1, "publish_time": "2025-05-15 17:40:27", "first_publish_time": null, "last_updated": "2025-05-27 19:30:26", "protected": false, "protected_to": null, "lang": "zh", "cstr": "33110.11.ariddc.00640", "license": null, "extra": null, "files_shape": [ { "name": "srtm90m_ca.gdb.rar", "size": 1004956141, "is_dir": false } ], "features": null, "data_level": 0, "i18n": { "en": { "title": "90mDEM data of five Central Asian countries in 2000", "ds_abstract": "The SRTM 90-meter resolution elevation data comes from NASA, and the data date is 2000. The SRTM data uses WGS84 ellipsoid projection. After pre-processing and processing the original downloaded data by the staff of our unit, a 90-meter DEM data set of the five Central Asian countries is obtained.(srtm90m_ca), the altitude value of the data is between-227 and 7050 meters, the empty data is represented by-32768, and the DEM data format is IMG grid image with a horizontal accuracy of 20 meters and an elevation accuracy of 16 meters. The data range is 45°-108° east longitude and 32°-56° north latitude.
", "ds_source": "SRTM (Shuttle Radar Topography Mission) 30-meter resolution elevation data is jointly measured by NASA and the Department of Defense's National Bureau of Surveying and Mapping (NIMA). The data volume of radar images acquired by the SRTM system is about 9.8 trillion bytes. After more than two years of data processing, a digital terrain elevation model (DEM), which is now SRTM3 terrain product data, has been produced.
", "ds_process_way": "Preprocessing: Use Arcmap10.2 software to open DEM elevation data, and get DEM data with normal altitude values (-227 - 7050 meters) through grid calculation and reclassification calculation. The data is obtained through clipping the borders of the five Central Asian countries.\nDEM rendering processing: Hillshade data (Zfactor=5) is generated from the pretreated DEM data, and the Hillshade data and DEM data are superimposed to generate DEM rendering. The rendering can be reprocessed by the user according to his or her needs.
", "ds_quality": "All processing processes did not destroy the data, and the attribute information of the original data was completely retained. The production of renderings only allows users to see the refinement of the data without adding other elements. The resolution of this data is 90 meters and can be used in conjunction with digital elevation data products with a resolution of 30 meters.
", "ds_format": ".fgdbr format", "ds_projection": "WGS84", "ds_space_res": "90", "ds_time_res": "no" } }, "license_type": null, "doi_reg_from": "reg_local", "cstr_reg_from": "reg_local", "doi_not_reg_reason": null, "cstr_not_reg_reason": null, "is_paper_in_submitting": false, "ds_topic_tags": [ "数字高程模型", "数字高程", "DEM" ], "ds_subject_tags": [ "地图学" ], "ds_class_tags": [], "ds_locus_tags": [ "塔吉克斯坦", "哈萨克斯坦", "土库曼斯坦", "乌兹别克斯坦", "吉尔吉斯斯坦" ], "ds_time_tags": [ 2000 ], "ds_contributors": [ "方晖" ], "ds_meta_authors": [ "方晖" ], "ds_managers": [ "李锦" ], "category": "DEM数字高程" }