Historical digital elevation models (DEMs) and orthoimage mosaics for North American Glacier Aerial Photography (NAGAP) program, version 1.0

This data archive contains digital elevation models (DEMs) and orthoimages generated from scanned historical aerial photographs from the North American Glacier Aerial Photography program available from the NSF Arctic Data Center (ADC, arcticdata.io). The scanned images were preprocessed using the Historical Image Pre-Processing v0.1 software. Photogrammetric processing was performed with the Historical Structure from Motion v0.1 software. All DEM and orthoimage products are provided in the UTM Zone 10N (EPSG:32610) projected coordinate system. Elevation values are in meters above the WGS84 ellipsoid. See manuscript and supplement for processing details and further dataset description. This release contains data products for two study sites in Washington state, USA: <strong>Mount Baker</strong><br> 1970-09-09<br> 1970-09-29<br> 1974-08-10<br> 1977-09-27<br> 1979-10-06<br> 1987-08-21<br> 1990-09-05<br> 1991-09-09<br> 1992-09-15<br> 1992-09-18 <strong>South Cascade</strong><br> 1967-09-21<br> 1970-09-29<br> 1974-08-10<br> 1977-10-03<br> 1979-08-20<br> 1979-10-06<br> 1984-08-14<br> 1986-09-05<br> 1987-08-21<br> 1990-09-05<br> 1991-09-09<br> 1992-07-28<br> 1992-09-15<br> 1992-09-18<br> 1992-10-06<br> 1994-09-06<br> 1996-09-10<br> 1997-09-23 The 00_thumbnails.jpg provides a quicklook overview at both sites. <strong>The DEM and ortho file names are structured as follows:</strong><br> hsfm_NAGAP_[site-name]_[date]_[type].tif <strong>For example:</strong><br> hsfm_NAGAP_south-cascade_19670921_ortho.tif <strong>Where:</strong><br> [site-name] = Either mount-baker or south-cascade<br> [date] = Image acquisition date in YYYYMMDD format<br> [type] = File type <strong>For each DEM and ortho pair, we provide the following:</strong><br> _1m_dem.tif = Digital elevation model posted at 1 m resolution <br> _ortho.tif = Orthoimage mosaic posted at the median image ground sample distance, rounded up to the nearest second decimal place.<br> _metadata.tar.gz = Metadata tarball containing:<br> _ortho_footprints.geojson = Orthoimage mosaic footprint polygons provided in GeoJSON format (EPSG:4326)<br> _dem_footprints.geojson = DEM footprint polygons provided in GeoJSON format (EPSG:4326)<br> _cameras.csv = Image file names, positions, and orientations本数据档案库包含由北美冰川航空摄影计划（North American Glacier Aerial Photography Program）扫描的历史航空照片生成的数字高程模型（Digital Elevation Models, DEMs）与正射影像（orthoimage），该数据集可从美国国家科学基金会北极数据中心（NSF Arctic Data Center, ADC, arcticdata.io）获取。扫描图像已通过Historical Image Pre-Processing v0.1软件完成预处理，摄影测量处理则采用Historical Structure from Motion v0.1软件完成。所有DEM与正射影像产品均采用UTM 10N（EPSG:32610）投影坐标系。高程值以WGS84椭球基准面的米为单位。有关处理细节与数据集的进一步说明，请参阅相关手稿及补充材料。 本版本包含美国华盛顿州两处研究站点的数据产品： <strong>贝克山（Mount Baker）</strong> 1970-09-09 1970-09-29 1974-08-10 1977-09-27 1979-10-06 1987-08-21 1990-09-05 1991-09-09 1992-09-15 1992-09-18 <strong>南喀斯喀特（South Cascade）</strong> 1967-09-21 1970-09-29 1974-08-10 1977-10-03 1979-08-20 1979-10-06 1984-08-14 1986-09-05 1987-08-21 1990-09-05 1991-09-09 1992-07-28 1992-09-15 1992-09-18 1992-10-06 1994-09-06 1996-09-10 1997-09-23 00_thumbnails.jpg可快速查看两处站点的概览图像。 <strong>DEM与正射影像的文件命名规则如下：</strong> hsfm_NAGAP_[站点名称]_[日期]_[类型].tif <strong>示例如下：</strong> hsfm_NAGAP_south-cascade_19670921_ortho.tif <strong>各字段说明：</strong> [站点名称] 可选值为 mount-baker 或 south-cascade [日期] 采用YYYYMMDD格式的影像获取日期 [类型] 文件类型 <strong>针对每一组DEM与正射影像对，我们提供以下文件：</strong> _1m_dem.tif = 分辨率为1米的数字高程模型 _ortho.tif = 正射影像镶嵌图，分辨率为影像的平均地面采样距离，向上取整至小数点后两位 _metadata.tar.gz = 元数据压缩包，包含以下文件： _ortho_footprints.geojson = 采用GeoJSON格式（EPSG:4326）存储的正射影像镶嵌图覆盖范围多边形 _dem_footprints.geojson = 采用GeoJSON格式（EPSG:4326）存储的DEM覆盖范围多边形 _cameras.csv = 包含影像文件名、拍摄位置与姿态参数的CSV文件