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Download Google Earth Elevation Data

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In late 2014, the United States government released the highest resolution SRTM DEM to the public. This 1-arc second global digital elevation model has a pixel size of about 30 meters resolution. Also, it covers most of the world with an absolute vertical height accuracy of less than 16m.


But over time, ASTER DEM data has improved its products with artifact corrections of their own. In October 2011, ASTER GDEM version 2 was publicly released, which was a considerable improvement. Despite its experimental grade, ASTER GDEM-2 is considered a more accurate representation than the SRTM elevation model in rugged mountainous terrain. But you should really take a look for yourself.



download google earth elevation data

Download File https://t.co/FNDJG1miQW 






Where can you download the MOLA DEM of Mars? The USGS Astrogeology Science Center is the DEM data hub for Mars. USGS found elevations above the areoid from a Martian gravity field solution GMM-2B with a total elevation uncertainty of at least 3m.


Personally I am very leery of the terrain information within Google Earth. There seems to be some issues with tree affecting the elevations in some areas within Google Earth, as well as some asymptotic like features where there should be none when drawing elevation profiles of a line.


By nature of the fact that they push it across the internet you can rest assured that the overall accuracy is very low. If you tried to push high accuracy elevation data across the web it would be very slow.


True but its not even necessarily an accuracy problem, but an outright error problem in some cases. I've never found anywhere that adequately explains the source of the terrain data in Google Earth, there has been alot of conjecture about its a combination of SRTM with other data in some places, but the fact I often find artifacts from trees would tend to lead me away from that. There are areas that you can find much higher quality terrain information in Google Earth where they have incorporated LiDAR or other high resolution data, but if you are outside of those areas, how useful the data is becomes highly questionable to me.


I would consider looking at the Terrain Elevation Layer from ESRI Living Atlas, they regularly incorporate higher resolution data into their Terrain Layer for use. Obviously you are working in some remote/not well sampled areas, but there should be at least some 24m meter data(as opposed to the 30m SRTM) from the AirBus data they incorporated lately.


ETOPO1 is a digital elevation model that includes both topography and bathymetry for the entire world. It consists of more than 233 million elevation values which are regularly spaced at 1 minute of latitude and longitude. At the equator, the horizontal resolution of ETOPO1 is approximately 1.85 kilometers. Vertical positions are specified in meters, and there are two versions of the dataset: one with elevations at the Ice Surface" of the Greenland and Antarctic ice sheets, and one with elevations at Bedrock" beneath those ice sheets. Horizontal positions are specified in geographic coordinates (decimal degrees). Source data, and thus data quality, vary from region to region.


GTOPO30 is a digital elevation model that extends over the world's land surfaces (but not under the oceans). GTOPO30 consists of more than 2.5 million elevation values, which are regularly spaced at 30 seconds of latitude and longitude. At the equator, the resolution of GTOPO30 is approximately 0.925 kilometers -- two times greater than ETOPO1. Vertical positions are specified to the nearest meter, and horizontal positions are specified in geographic coordinates. GTOPO30 data are distributed as tiles, most of which are 50 in latitude by 40 in longitude.






The days of data shortage are gone. More and more DEM data sets are published under free licenses or as public domain. Through INSPIRE in Europe more and more will follow. The datasets below are not complete. This project will focus on free high resolution datasets with a spatial resolution of 30 meters and below on county/state scale. Have a look at the OpenDemSearcher map client on this website.


- OpenTOPO: Community lidar datasets

 - LAZIP: Download free and lossless LiDAR compression data

 - Wikipedia National Lidar Dataset

 - Wikipedia National Lidar Dataset (United States)

 - ArcGIS OpenData Catalog

 - OpenTerrain List




The data provided from the cloud has an overall accuracy of nearly one sample every 30 meters. If you specify a smaller value in the Elevation data settings, Lands will generate the interpolated samples automatically.


U.S. Releases Enhanced Shuttle Land Elevation Data On September 23, 2014, the White House announced that the highest-resolution topographic data generated from NASA's Shuttle Radar Topography Mission (SRTM) in 2000 was to be released globally by late 2015. The announcement was made at the United Nations Heads of State Climate Summit in New York. Since then the schedule was accelerated, and all global SRTM data have been released.


Previously, SRTM data for regions outside the United States were sampled for public release at 3 arc-seconds, which is 1/1200th of a degree of latitude and longitude, or about 90 meters (295 feet). The new data have been released with a 1 arc-second, or about 30 meters (98 feet), sampling that reveals the full resolution of the original measurements.


Indonesia, with many volcanoes, starting at Bali, flying westward over Java, and ending at Krakatoa (Pulau Krakatau). This fly around uses only SRTM data, shaded and with colored height. View the movie here.


Below, shaded relief images of deeply eroded volcanic terrain in northeast Tanzania demonstrate the improved nature of the highest-resolution SRTM data now being released. The image at left has data samples spaced every 90 meters (295 feet); the image at right has samples spaced every 30 meters (98 feet).

Credit: NASA/JPL-Caltech/National Geospatial Intelligence AgencyClick on the image for a detailed comparison, including an animation


NASA has released a void-filled version of the Shuttle Radar Topography Mission digital elevation model, known as "SRTM Plus" or SRTM NASA Version 3. SRTM Plus uses SRTM Version 2 (see below) where the radar interferometric method was successful (not void). Most voids are filled with elevation data from the ASTER GDEM2 (Global Digital Elevation Model Version 2). ASTER is a sensor on NASA's Terra satellite that uses stereoscopic imaging to measure elevations via optical parallax where not obscured by clouds. Additional void filling of small areas used the GMTED2010 elevation model compiled by the US Geological Survey. SRTM Plus was produced under NASA's "Making Earth System Data Records for Use in Research Environments" (MEaSUREs) Program.


Engineers and scientists at JPL are currently working on a complete reprocessing of the original SRTM radar data in order to produce an improved near-global digital elevation model (DEM) to be called NASADEM. As with SRTM Plus, this work is funded under NASA's "Making Earth System Data Records for Use in Research Environments" (MEaSUREs) Program. In brief, the expected improvements include (1) fine vertical adjustments within and among individual shuttle data takes via reference to precise ICESat (Ice, Cloud, and land satellite) laser profiles, (2) void reduction via improved radar interferometric processing, (3) use of better fill data in the remaining voids, especially ASTER GDEM3 when available, and (4) improved quality assessments and adjustments. This project is scheduled for completion in 2017, but we expect to release interim products in 2016 and early 2017.


NASA has released version 2 of the Shuttle Radar Topography Mission digital topographic data (also known as the "finished" version). Version 2 is the result of a substantial editing effort by the National Geospatial Intelligence Agency and exhibits well-defined water bodies and coastlines and the absence of spikes and wells (single pixel errors), although some areas of missing data ('voids') are still present. The Version 2 directory also contains the vector coastline mask derived by NGA during the editing, called the SRTM Water Body Data (SWBD), in ESRI Shapefile format.


That maxim is especially true when considering elevation data, which forms the foundation of various applications in the geospatial mapping industry. The strength of that foundation depends on the data's accuracy. Whether creating Earth elevation models or building 3D simulations, all the details matter. Failing to prioritize accuracy can lead to uncertain decisions and inconsistent results. It can also make the difference between a project's success and failure.


Earth elevation models have improved dramatically in recent decades. By applying new technologies and algorithms to satellite and airborne platform sensors, users have increased the resolution limits of elevation models by orders of magnitude over previous options. In this new era, the challenge is processing and managing millions of elevation values efficiently and accurately before integrating them into sophisticated, widely used applications.


The accuracy of elevation data is critical because it affects the accuracy of results. Positional errors, terrain distortions, incorrect flood plain delineations, inadequate construction designs, and increased costs are some of the byproducts of inaccurate elevation data.


L3Harris provides comprehensive elevation data for local and worldwide coverage and creates customized models that help users predict, anticipate, prepare for, identify, and address any challenges they might face. So, how do our experts quickly transform raw satellite data into accurate, precise elevation data users can trust?


Orthorectification removes distortions and aligns aerial and satellite images, producing imagery that is georeferenced and geometrically accurate. Elevation data such as digital elevation models (DEMs) and digital terrain models (DTMs) play an essential role in orthorectification. During the orthorectification process, we use height values within the elevation data to remove perspective distortion from images. This results in more precise ground positions of each pixel in orthorectified images.

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Download Google Earth Elevation Data Tuula Sturk <sturktuula@gmail.com> - 2024-01-18 22:17 -0800

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