In+ersec+ion for Spatial People

We mentioned TanDEM-X before, TerraSAR-X too, and global DEMs like SRTM-DEM and ASTER GDEM, and there's going to be a new major global DEM available in 2014, WorldDEM.

From the DM article: "The TanDEM-X mission is to generate a global digital elevation model - WorldDEM - of unprecedented quality, accuracy and coverage. This DEM is intended to be the replacement dataset for SRTM and will be available in 2014 for the Earth’s entire land surface - pole to pole. The accuracy of the WorldDEM will surpass that of any satellite-based elevation model available today and will have the following unique features:

• Vertical accuracy of 2m (relative) and 10m (absolute)
• 12m x 12m raster
• Global homogeneity
• Highly consistent dataset as a result of an initial global data collection window of 2.5 years and the opportunity to continue to collect locally beyond the initial collection period
• No need for ground control information due to the high geometric precision of German sensors "

This is major news for anyone using DEM datasets. Here's about a new elevation dataset named Global Multi-resolution Terrain Elevation Data 2010 - GMTED2010. Here's the USGS report about GMTED2010 and the description and download site on USGS's EROS.

From the article: "The U.S. Geological Survey (USGS) and the National Geospatial-Intelligence Agency (NGA) have released an updated and more accurate global elevation model that pulls data from Digital Terrain Elevation Data (DTED®) from the Shuttle Radar Topography Mission (SRTM); Canadian elevation data; SPOT 5 Reference 3D data; data from NASA’s Ice, Cloud, and land Elevation Satellite (ICESat); and updated Antarctica and Greenland terrain models. This new elevation data called Global Multi-resolution Terrain Elevation Data 2010 (GMTED2010),  replaces the thirty year old GTOPO30 terrain model.

GMTED2010 is a suite of seven raster data products: minimum elevation, maximum elevation, mean elevation, median elevation, standard deviation of elevation, systematic subsample, and breakline emphasis. The spatial resolution of GMTED2010 ranges from 30, 15 and 7.5 arc-seconds (approximately 1 kilometer, 500 meters and 250 meters, respectively)."

You might be interested in the ASTER GDEM and the SRTM-DEM CGIAR-CSI v4 datasets, amongst other DEMs.

It's featured as today's Astronomy Picture of the Day, but it's also discussed over Slashdot in a story named High Resolution Global Topographic Map of Moon.

The APoD summary: "This colorful topographical map of the Moon is centered on the lunar farside, the side not seen from planet Earth. That view is available to the Lunar Reconnaissance Orbiter though, as the spacecraft's wide angle camera images almost the entire lunar surface every month. Stereo overlap of the imaging has allowed the computation of topographical maps with coverage between 80 degrees north and south latitude. The results have about a 300 meter resolution on the lunar surface and 10 to 20 meter elevation accuracy. Data closer to the north and south poles is filled in using the orbiter's laser altimeter. In this map, white, red, green, and purple represent progressively lower elevations. In fact, the large circular splotch tending to purple hues at the bottom is the farside's South Pole-Aitken Basin. About 2500 kilometers in diameter and over 12 kilometers deep, it is one of the largest impact basins in the Solar System."

In June 2009 we announced the release by the METI and NASA of the free global topography dataset named "ASTER GDEM", and Version 2 with significant improvements has just been released earlier this month.

From the article: "The improved version of the map adds 260,000 additional stereo-pair images to improve coverage. It features improved spatial resolution, increased horizontal and vertical accuracy, more realistic coverage over water bodies and the ability to identify lakes as small as 0.6 miles (1 kilometer) in diameter. The map is available online to users everywhere at no cost. [...] The ASTER data cover 99 percent of Earth's landmass and span from 83 degrees north latitude to 83 degrees south. Each elevation measurement point in the data is 98 feet (30 meters) apart."

Here's a direct link to the ASTER GDEM website. See also previous news regarding ASTER GDEM. Of course, if you have an interesting in the ASTER GDEM, make sure you know about the SRTM-DEM CGIAR-CSI Version 4 too.

Here's the articles publish last month over Directions Magazine that I wanted to share with our users.

• An informative article named NoSQL Databases:  What Geospatial Users Need to Know. If you never heard of NoSQL, now is the time to learn about it.
• An article on "GISCI's Executive Director Sheila Wilson writes about the addition of an exam to the GISP certification process. She addresses "the history of the debate, where we stand now, and the options being discussed by the GIS Certification Institute (GISCI).""
• An article on the economics and ROI of DEM data in the case of the recent Australian floods: "David Hocking, chief executive officer of the Spatial Industries Business Association (SIBA) in Australia, looks at the government’s position of slow investment in developing a nationwide digital elevation model (DEM) despite the financial impact of the floods."
• An informative aggregation of reactions to the U.S. Nationwide Broadband Map. There's also and Q&A with Connected Nation, a non-profit organization that is promoting broader adoption of broadband access.
• An article on Loc8 Codes, a system to tackle the problems of addresses in Ireland.

Via the OSM blog, I learned about the new OpenDEM.info project.

From the site: "There are many ways to record the earth´s surface:

1. Aerial photography
2. Remote sensing
3. Microdrones
4. GPS
5. Trachymeter
6. …

If you have any height data that could be licensed under the Open Database License or current OSM license (CC-BY-SA), please provide the dataset, so it can be used by the project."

So far, they seem to offer very little datasets, but don't all projects have to start somewhere? I guess they should include, if they can license-wise, the CGIAR-CSI SRTM-DEM Version 4 and ASTER GDEM amongst already free and available DEMs. There are plenty of already free DEM datasets that probably can't be added to OpenDEM due to licensing issues, such as Canada's CDED.

Two German radar satellites are now flying in tight formation as they prepare to make the most detailed ever 3D map of the Earth's entire surface.

From the BBC News article: "TanDEM-X and TerraSAR-X have moved to within 350m of each other as they sweep around the planet at 7km/s. [...] TerraSAR-X was launched in 2007. TanDEM-X was put in space in June, since when it has been brought closer and closer to its more established sibling. [...] The fully finished DEM of the Earth's surface should be available in 2014. [...] With the TanDEM mission, the intention is to go down to a spatial resolution of 12m by 12m with a relative vertical accuracy of less than two metres."