GLOVIS Download Procedure

The ASTER download procedure that I reported in a previous article used the old interface at the EOS Data Gateway. The GLOVIS user interface offers a much more convenient method for browsing and ordering ASTER data. GLOVIS is useful for ordering ASTER as well as several other types of data. To use it, enter the EOS Data Gateway website and select the 'GloVis' under the 'Data Access' menu on the upper left side of the screen. A screen like the one at the top left will appear.

Suppose you are looking ASTER data in eastern Brazil, inland of Recife. The default data set is Landsat. Click on the global map and a single grid node will be highlighted. A viewer like the one at the right will appear. Row and grid as well as latitude and longitude coordinates will be displayed. If this is not the right node you move the viewer using the four arrow keys.

Select 'Collection' from the menu at the upper left of the viewer and the select 'ASTER' and either VNIR or TIR, depending on what you would like to see in the viewer. (Note: this selection has nothing to do with what you will order. That selection will be made from the standard list of ASTER products later.) Also, select the maximum degree of cloud cover that you can tolerate. For ASTER DEMs this should ideally be zero. Once you are in the right vicinity, simply select the ASTER tile or tiles of interest, as in the third figure at rig

Once you have selected your image, add it to your list by selecting the 'Add' button at the lower left of the viewer. When you are done selecting images, select the 'Order' button and the order screen will be presented. If you want to see a browse image of your selection, choose 'File', 'Download Scene List Browse and Metadata'. IMPORTANT: do not choose any other selection unless you want ALL of the browse images in view or in the path downloaded. This could be a lot of data.

Now it is time to select the ASTER data product you are interested in. For example, if you want an ASTER DEM, choose 'AST14DEM' from the drop down menu. If you want the DEM plus the orthorectified images, choose 'AST14DMO'. (The full description of the data products is listed on the EOS Data Gateway website.) Also select how you will access the data, either FTP pull or DVD and the file format. The price will be automatically adjusted according to your selection. When you are done specifying your product, select 'Go to Checkout' and fill out the order information.

This interface is much more intuitive, useful and convenient than the previous rubber band box on a global map method. The server seems to respond much faster than the standard interface as well.