该数据集包括ASTER GDEM数据及其镶嵌图。
\n\nASTER Global DEM（简称ASTER GDEM）是美国是美国航空航天局 (NASA )和日本经济产业省(METI)于2009年6月29日联合发布的全球数字高程数据产品, 该DEM数据是根据NASA新一代对地观测卫星TERRA的观测结果完成，是由ASTER(Advanced Space borne Thermal Emission and Reflection Radio meter)传感器搜集的130万个立体像对数据制作，其覆盖范围超过了地球99%陆地表面。该数据的水平精度30米（置信度95%），高程精度为7-14米（置信度95%）。该数据是第三个全球范围内的高程数据，较之以前的SRTM3 DEM和GTOPO30数据有明显的提高。
\n\n我们从NASA数据网站上（http://wist.echo.nasa.gov/api）下载了黑河流域的数据，并通过本数据中心重新分发。本中心分发的数据完全保留了数据的原貌，没有对数据进行任何修改。用户如需详细了解ASTER GDEM的制备过程，请参考本元数据连接的数据文档，或直接访问http://www.ersdac.or.jp/GDEM/E/3.html or from https://lpdaac.usgs.gov/阅读与ASTER Global DEM 相关的文档.
\n\nASTER GDEM在分发是被分割为若干1×1度的数据块，分发格式为zip压缩格式，每个压缩文件包括三个文件，文件命名格式如下：
\n\nASTGTM_NxxEyyy_dem.tif
\n\nASTGTM_NxxEyyy_num.tif
\n\nreademe.pdf
\n\n其中xx为起始纬度，yyy为起始经度。_dem.tif为dem数据文件，_num.tif为数据质量文件，reademe为该数据说明文件。
\n\n为了便于用户使用数据，在分幅ASTER GDEM数据的基础上，我们将分数SRTM数据进行拼接制备了黑河流域ASTER GDEM镶嵌图，该数据保留了ASTER GDEM的全部原始特征，没有经过任何重采样处理。 本数据包括两个文件： Heihe_ASTER_GDEM_Mosaic_dem.img Heihe_Aster_GDEM_Mosaic_num.img
\n\n数据采用Erdas image格式存储,其中_dem.img文件是dem数据文件，_num.img是数据质量文件。
", "ds_source": "ASTER Global DEM
", "ds_process_way": "数据进行了拼接，保留了ASTER GDEM的全部原始特征，没有经过任何重采样处理。
", "ds_quality": "数据质量良好
", "ds_acq_start_time": "1999-01-04 00:00:00", "ds_acq_end_time": "2009-12-31 00:00:00", "ds_acq_place": "黑河流域", "ds_acq_lon_east": 104.19972222222222, "ds_acq_lat_south": 37.7, "ds_acq_lon_west": 96.01666666666667, "ds_acq_lat_north": 43.25, "ds_acq_alt_low": null, "ds_acq_alt_high": null, "ds_share_type": "login-access", "ds_total_size": 1118294597, "ds_files_count": 3, "ds_format": "栅格数据", "ds_space_res": null, "ds_time_res": "", "ds_coordinate": "WGS84", "ds_projection": "+proj=longlat +datum=WGS84 +no_defs ", "ds_thumbnail": "af25f2d2-1d5f-4dc2-81be-3915d83f70e0.png", "ds_thumb_from": 0, "ds_ref_way": "", "paper_ref_way": "", "ds_ref_instruction": "数据下载于ASTER GDEM分发网站（ http://www.gdem.aster.ersdac.or.jp/index.jsp）,用户在使用数据时需声明:\"ASTER GDEM is a product of METI and NASA\"", "ds_from_station": null, "organization_id": "9c4867b1-5cb1-4de0-abeb-df42547bf41e", "ds_serv_man": "黑河计划数据管理中心", "ds_serv_phone": "0931-4967287", "ds_serv_mail": "westdc@lzb.ac.cn", "doi_value": "", "subject_codes": [ "170.4510" ], "quality_level": 3, "publish_time": "2020-12-18 14:50:13", "last_updated": "2023-08-23 16:46:58", "protected": false, "protected_to": null, "lang": "zh", "cstr": "11738.11.ncdc.Westdc.2020.457", "i18n": { "en": { "title": "The ASTER GDEM dataset in the Black River Basin", "ds_format": "Raster", "ds_source": "ASTER Global DEM
", "ds_quality": "Good data quality
", "ds_ref_way": "", "ds_abstract": "The dataset includes aster GDEM data and its mosaic.
\nAster global DEM (Aster GDEM) is a global digital elevation data product jointly released by NASA and METI on June 29, 2009, The DEM data is based on the observation results of Terra, a new generation of earth observation satellite of NASA. It is made of 1.3 million stereo image pairs collected by aster (advanced space borne thermal emission and reflection radio meter) sensor. Its coverage exceeds 99% of the earth's land surface. The horizontal accuracy of the data is 30 meters (95% confidence), and the elevation accuracy is 7-14 meters (95% confidence). This data is the third global elevation data, which is significantly higher than the previous SRTM3 DEM and gtopo30 data.
\nWe downloaded the data of Heihe River Basin from NASA data website (http://wish.echo.nasa.gov/api) and redistributed it through this data center. The data distributed by the center completely retains the original appearance of the data without any modification. If you need to know more about the preparation process of Aster GDEM, please refer to the data document of this metadata connection, or directly visit http://www.ersdac.or.jp/gdem/e/3.html or from https://lpdaac.usgs.gov/ to read the documents related to aster global DEM
\nAster GDEM is divided into several 1 × 1 degree data blocks in the distribution format of zip compression. Each compressed file includes three files. The file naming format is as follows:
\nASTGTM_NxxEyyy_dem.tif
\nASTGTM_NxxEyyy_num.tif
\nreademe.pdf
\nWhere XX is the starting latitude and YYY is the starting longitude. _Dem.tif is the DEM data file, and \"num.tif\" is the data quality file. READEME is the data description file.
\nIn order to facilitate the user's use of data, based on the segmented aster GDEM data, we spliced the fractional SRTM data to prepare the aster GDEM mosaic map of Heihe River Basin, which retains all the original features of Aster GDEM without any resampling. This data includes two files: Heihe ﹣ aster ﹣ GDEM ﹣ mosaic ﹣ dem.img Heihe ﹣ aster ﹣ GDEM ﹣ mosaic ﹣ num.img
\nThe data is stored in ERDAS image format, where the dem.img file is the DEM data file and the num.img file is the data quality file.
", "ds_time_res": "", "ds_acq_place": "Heihe River Basin", "ds_space_res": "", "ds_projection": "+proj=longlat +datum=WGS84 +no_defs ", "ds_process_way": "The data is spliced, and all the original features of Aster GDEM are preserved without any resampling.
", "ds_ref_instruction": "The data is downloaded from Aster GDEM distribution website (http://www.gdem.aster.ersdac.or.jp/index.jsp). When using the data, users need to declare: \"aster GDEM is a product of METI and NASA\"" } }, "submit_center_id": "ncdc", "data_level": 0, "license_type": "CC BY 4.0", "doi_reg_from": "reg_local", "cstr_reg_from": "reg_local", "doi_not_reg_reason": null, "cstr_not_reg_reason": null, "ds_topic_tags": [ "数字高程模型", "GDEM", "DEM", "ASTER" ], "ds_subject_tags": [ "自然地理学" ], "ds_class_tags": [], "ds_locus_tags": [ "黑河流域" ], "ds_time_tags": [ 2009 ], "ds_contributors": [ { "true_name": "黑河计划数据管理中心", "email": "westdc@lzb.ac.cn", "work_for": "中国科学院西北生态环境资源研究院", "country": "" } ], "ds_meta_authors": [ { "true_name": "黑河计划数据管理中心", "email": "westdc@lzb.ac.cn", "work_for": "中国科学院西北生态环境资源研究院", "country": "" } ], "ds_managers": [ { "true_name": "黑河计划数据管理中心", "email": "westdc@lzb.ac.cn", "work_for": "中国科学院西北生态环境资源研究院", "country": "" } ], "category": "基础地理" }