Usage of dataencoded web maps with client side color. Srtm is probably of better quality than the aster gdem, but lower. Download aster global dem data from earth explorer youtube. The first version of the aster gdem, released in june 2009, was generated. Aster global digital elevation model version 2 summary of. Download of most images if for free for users, but for some inc. Ive also decided to ease my licensing limitation a bit and release the entire 90 meter global terrain map under the creative commons attribution license. Aster global dem version 3, and new aster water body dataset. The gdem is produced with 30meter 98feet postings, and is formatted as 23,000 onebyone degree tiles. Since then, i have had numerous requests to create high resolution terrain maps of other countries and regions. Srtm data, in hgt format, can be downloaded from here, but for some. Aster gdem data are posted on a 1 arcsecond approximately 30 metres at the equator grid and referenced to the 1984 world geodetic system wgs84 1996 earth gravitational model egm96 geoid, and comes in geotiff. As i understand from reading the data pdf file associated with the gmted2010 it is a collection and aggregation of different dem datasets including strm.
I also converted it to a geotiff in globalmapper just to make sure it got the coordinate data. Usgs disaster response ftp site optical data from recent disasters. At the end of the selection process, you will receive email instructions on downloading your data via ftp. Srtm is probably of better quality than the aster gdem, but lower quality than the 1 usgs nedgdep. A lot more noise in the aster dem, and it also appeared to be less accurate. Dear sir aster is a 15 m resolution data and srtm is 3 arc second 90m so certainly aster is better, we have developed set methodoology and was quite successful. Srtm dem automatically downloaded as needed by nest. Chrysoulakis university of athens, department of geology and geoenvironment, remote sensing. However i am having an issue with the bit depth of the provided data. To download a file on the right side, there is remote site section that looks like a file system directory and files.
Wist or the aster gdem ordering site, maintained by the earth remote. The aster gdem is the most uptodate, high spatial resolution, complete digital topographic data set of the earth available at no cost to the public, covering. The tools are grouped loosely into broad categories that indicate the primary function of each tool, for example, data handling. You could also try version 2 of the 1arcsecond aster global dem which is also available through the usgs earthexplorer site. So just cut away the stuff thats not meant to be there and you are good to go. It is generally acknowledged that the srtm3 data are superior to aster gdem in terms of vertical accuracy in the lowrelief areas jacobsen, 2010, zhao et al. On successful authentication, the remote ftp server and its accessible folders will be visible. Hi, i am a student at the university of bergen in norway working on a project trying to characterize the sediment runoff behaviour using dems. The server hosting the aster gdem data is frequently extremely busy and thus very slow to pull from. Performance is all right if wms server able to serve elevation tiles within less than 3 sec wwj client timeouts after 9 seconds, otherwise you would need to try next level 0.
Sentinel download is on requestor pays basis, ie downloading costs a little bit. To upgrade your browser, click on the icons below to go to the download page. If you just want a few of the available results, click on each tile you would like to download in the results pane then the download single granule data button. The aster gdem covers land surfaces between 83n and 83s and is comprised of. Jun 29, 2009 the gdem was created by processing and stereocorrelating the 1.
Aster global digital elevation model gdem has generated one of the most complete highresolution digital topographic data sets of the world to date. Introduction the advanced spaceborne thermal emission and reflection radiometer aster global digital elevation model gdem was developed jointly by the ministry of economy, trade, and industry meti of japan and the united states national aeronautics and space administration nasa. These areas a nearly okay in csi so i could fill these errors of the aster gdem2 with it. In the search box type aster gdem and select dataset note if you want a. The absolute vertical accuracy of gdem v3 was calculated by comparison with more than 23,000 independent reference geodetic ground control points from the u. The aster gdem is a joint contribution by nasa and the ministry of economy, trade and industry of japan meti to the global earth observation system of systems geoss. I decided to use aster gdem2 for different reasons. Apr 20, 2012 aster global digital elevation map tweet so a project required highresolution shaded relief for parts of borneo, so i thought i would check out the aster global digital elevation map, which is a 30m digital elevation model for use in gis software. Free satellite data terrainmap satellite image analysis. Which dem data is better for elevation mapping, aster or srtm. Since it is in spanish, im reproducing it in english.
The biggest problem with srtm is holes, which occur mostly in two settings. Pdf evaluation of aster gdem using gps benchmarks and. The srtm 90m dems have a resolution of 90m at the equator, and are provided in mosaiced 5 deg x 5 deg tiles for easy download and use. Characterization of aster gdem elevation data over vegetated area compared with lidar data. Creating contours using aster dem and global mapper.
Usgs seamless data distribution or more conveniently at the ftp site. After half hour we got an email with the ftp link to download the data. The aster global digital elevation model version 3 gdem v3 was evaluated over the conterminous united states in a manner similar to the validation conducted for the original gdem version 1 v1 in 2009 and gdem version 2 v2 in 2011. Aster l1t data are available to all users at no cost. All swir data collected after 1 april 2008 has been marked as unusable. Meanwhile, the 101st or later tiles are recorded in backlog, and prepared to be downloaded when system has enough resources. Mar 18, 20 i have been trying to use aster data to use as a dem in cityengine. Highquality seamless dem generation blending srtm1, aster. Space images asters global digital elevation model gdem.
Caelinux caelinux is an installable live dvd linux distribution dedicated to open source engineering with a f. The links provided in the category tables below list and describe some of these available datahandling and service tools. The project centers on the use of open gdem datasets such as those from srtm and aster for important geospatial modeling such as watershed deliniation, floodplain modeling, and erosion control planning to name a few. We have restarted batch download for up to 100 tiles. Yet we havent done the math and this noise might result from our blackwhite color stretch. Dont get me wrong though, its a fantastic data set. Jul 02, 2009 agustin castillo has a nice short tutorial on how to download aster gdem tiles. Unrestricted 30 day trial alternatively, if you can tell us a bit about yourself, our system will send you a free 30day, unrestricted subscriptioncode to the most feature rich edition of the software. Gis software download aster nasa geo dem and building. Aster gdem global digital elevation model v002 select search for granules now begins the tedious part where there are over 22,000 aster gdem tiles that cover the globe however, the website only list 400 per page where there is an add all on page button but no add all option i. Advanced spaceborne thermal emission and reflection. Its offerings were gradually curtailed over the year. May 06, 2017 download data aster l1t melalui dan membukanya d qgis music. During your trial period, bulletproof ftp server is limited to 1 ftp accounts and 2 connections to the ftp server.
Agustin castillo has a nice short tutorial on how to download aster gdem tiles. The second version of the advanced spaceborne thermal emission and reflection radiometer global digital elevation model aster gdem is a stateoftheart global. Updated version of global elevation data nasadem arab. Aster global digital elevation model gdem overview the advanced spaceborne thermal emission and reflection radiometer. If anyone would like to mirror these files on ftp server or traditional web server, please contact me. For the anonymous user with accessible pub directory 04. It appears that the global 1arcsecond 30m srtm digital elevation model is now being made publicly available through, for example, the united states geological surveys earthexplorer site.
Srtm 90m digital elevation database cgiar platform for. If you try to download more than 100 tiles, the first 100 tiles are immediately downloaded. I dont know how to get data with native resolution. The ministry of economy, trade, and industry meti of japan and the united states national aeronautics and space administration nasa jointly announced the release of the advanced spaceborne thermal emission and reflection radiometer aster global digital elevation model version 3 gdem 003, and the aster water body dataset astwbd on. Aster data can be found from several sources, but i find the earth explorer site to be the most intuitive option. Lpdaac gtopo30 coarse scale 1km dem data nga raster roam. Right now, im trying to download aster gdem for all of nigeria. Detailed description and download link can be found in the table below. Was difficult to veriy if the land actually did slope up, but as far as we could determine, it was wrong in the aster dem. Comparing dems of singapore maps and spatial analysis.
The aster gdem is in geotiff format with geographic latlong coordinates and a 1 arc. In order to use earthdata search, you must upgrade your web browser. Japan validation team assessed the accuracy of the gdem1, augmented by a team of 20 cooperators. Open gis data services for research csc company site. Also, pay attention to the performance of the wms server. The eosdis distributed active archive centers daacs provide centerunique tools for functions such as searching and subsettting data. We saw the aster data sloping up, while the dted2 did not. In april 2008, the swir detectors of aster began malfunctioning and were publicly declared nonoperational by nasa in january 2009. Nasa has released version 2 of the shuttle radar topography mission digital topographic data also known as the finished version. Best source for aster gdem v2 and srtm data using the seamless server. Each of these parameters are encoded with the color depth of 16 bit thus making it possible to merge them within the same set of data. If you want to download all the tiles 4 in this example, click the download all button. This interface attempts to ease the pain of downloading 30meter resolution elevation data from the shuttle radar topography mission click on yellow tiles to download their corresponding data tiles come as zipped srtmhgt files at 1arcsecond resolution 3601x3601 pixels in a latitudelongitude projection, downloaded from nasa servers. For example, the aster global digital elevation model currently uses separate geotiff formatted files to store the data and the associated precision parameters.
Digital elevation data with srtm voids filled using accurate. The gdem and astwbd are available for download from nasa earthdata and. Aster gdem2 have its problems, i know, and i dont want to discuss that again. Sep 25, 2014 absolute differences between srtm and aster gdem. This version 1 aster gdem gdem1 was compiled from over 1. After the download process is finished, you should go for tools and then re download.
Version 2 is the result of a substantial editing effort by the national geospatial intelligence agency and exhibits welldefined water bodies and coastlines and the absence of spikes and wells. Srtm vs gmted2010 dem data geonet, the esri community. Free digital elevation model dem and free satellite data. How to install and configure an ftps server in centos. It is particularly suited to problems involving heat transfer, mechanics, fluids, and fluidstructure interactions. Restart wms server, clean elevations cache on your wwj client. As such, both meti and nasa desire to understand the uses of the aster gdem, expressed as one the geoss applications themes. As you might have seen, the data in the aster gdem looks a little bit noisy.
The earlier released aster geoscience maps of western australia released 15. Validation of the aster global digital elevation model. The aster gdem version 1 was released in july 2009 and the version 2, now under processing, will be released in the october 2011. Basically, you create a wist account for yourself, specify the region you want to download aster data for, go through an ordering process data is all free, and submit your order. We first used bilinear resampling to aggregate aster gdem2 data to 3 arcsec resolution, and to shift grids. All are produced from a seamless dataset to allow easy mosaicing. Select a file, then rightclick to open the context menu. Version 2 is the result of a substantial editing effort by the national geospatial intelligence agency and exhibits welldefined water bodies and coastlines and the absence of spikes and wells single pixel errors. Srtm data is usually available direct from nasas website no longer ftp. The aster global digital elevation model gdem is available at no charge to users worldwide via electronic download. The new and improved srtm elevations in nasadem result from better vertical control of each srtm data. I cut the grid from 32 to 100 to 300m and still no luck.
Digital elevation models dem for the entire globe, covering all of the countries of the world, are available for download on this site. Jrc, image2000, corine land cover projects satellite image mosaic. Now i am a little confused as to the difference or advantage of gmted2010 vs srtm data. This will list the aster gdem tiles that intersect your area of interest rectangle. This interface attempts to ease the pain of downloading 30meter resolution elevation data from the shuttle radar topography mission click on yellow tiles to download their corresponding data. The nima raster roam site used to be an interesting and eclectic source of dem and satellite image data. Also, aster gdem distribution site will be suspended due to this update. Global mapper downloads very quickly whole area, but it doesnt look like full resolution map. The gdem was created by processing and stereocorrelating the 1. Nasa released the free global digital elevation model nasadem on february 2020 nasadem is a nearglobal elevation model that is being produced primarily by completely reprocessing the shuttle radar topography mission srtm radar data and then merging it with refined aster gdem elevations. The university of hawaii coastal geology group has made available a large collection of shoreline aerial photographs that date back to 1949. Scene information is displayed along with the browse image.
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