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The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is a 14-channel imaging instrument operating on NASA's Terra satellite since 1999. ASTER's visible-near infrared (VNIR) instrument, with three bands and a 15 m Instantaneous field of view (IFOV), is accompanied by an additional band using a second, backward-looking telescope. Collecting along-track stereo pairs, the geometry produces a base-to-height ratio of 0.6. In August 2019, the ASTER Science Team released Version 3 of the global DEM (GDEM) based on stereo correlation of 1.8 million ASTER scenes. The DEM has 1 arc-second latitude and longitude postings (~30 m) and employed cloud masking to avoid cloud-contaminated pixels. Custom software was developed to reduce or eliminate artifacts found in earlier GDEM versions, and to fill holes due to the masking. Each 1×1 degree GDEM tile was manually inspected to verify the completeness of the anomaly removal, which was generally excellent except across some large ice sheets. The GDEM covers all of the Earth's land surface from 83 degrees north to 83 degrees south latitude. This is a unique, global high spatial resolution digital elevation dataset available to all users at no cost. In addition, a second unique dataset was produced and released. The raster-based ASTER Global Water Body Dataset (ASTWBD) identifies the presence of permanent water bodies, and marks them as ocean, lake, or river. An accompanying DEM file indicates the elevation for each water pixel. To date, over 100 million 1×1 degree GDEM tiles have been distributed. 200,000 scenes to fill holes, and to improve infilling of the few holes remaining. The methodology used to produce the most recent GDEM is described in this contribution.In addition to the improved GDEM Version 3, a second, unique dataset was created and released: the ASTER Global Water Body Dataset (ASTWBD). The ASTWBD is the only near-global raster dataset that delineates all water bodies smaller than 0.2 km 2 . The dataset defines the type of water body and identifies each water pixel as ocean, lake or river; an accompanying elevation file reports the elevation for each water pixel. The processing methodology is described below.

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