Access to data

The following paragraphs describe some ways to get SAR data from ERS, Envisat, JERS, Radarsat, TerraSAR-X, and ALOS PALSAR. A separate page will be created to describe how to get access to optical data from ASTER. We need someone to write information about the other satellite systems.

To make a general comprehensive search for data (particularly from ERS and Envisat), we recommend the EOLISA program from the European Space Agency which will run on Mac, Windows or LINUX. If you would like to get information on the Perpendicular Baseline between different image pairs, the best available resource is ESA's DESCW program which only runs on Windows. You can supposedly get Baseline information on EOLISA, but I've never gotten this to work 100% of the time. For data archived at ASF, you can get Baseline info whenever you look at the results of a data search and a "Baseline Info" link appears to be clicked on.

To gain access for ERS and Envisat ASAR data (either image or wide swath modes), you can write a ESA Cat-1 proposal to ESA. As of 2010, the data is now available at no cost. You need to describe your scientific objectives, how much data you need and of what type and ESA will review your proposal and give you an answer within a few months.

For selected spots in the world, data from a variety of sources (including SAR, GPS, etc.) have been made available at no cost for the purpose of better understanding hazards. These spots are called supersites, and include major volcanoes (Hawaii, Mt. Etna), areas where recent earthquakes have occurred (for example, Haiti), and areas where future earthquakes will occur (for example, Tokyo, Los Angeles, Vancouver). Some data is available on the supersites for immediate download, while others requires you to obtain a password.

For U.S. based academic/research scientists (and potentially some others)

There are 2 data archives available at each UNAVCO and ASF where you can get different types of data over different regions.

WInSAR data is available to WInSAR members (academic and research institutions). Membership is free, but you need to apply here. Data in the WInSAR archive includes ERS, Envisat and a very little Radarsat data, and maps of the geographic areas covered by the data are available here. note: to rename WINSAR data to ROI_PAC's convention, cd to the data directory and run "perl read_winsar.pl".

Thanks to a new agreement with the German Space Agency (DLR), some TerraSAR-X data is now available in WInSAR. Please see the TerraSAR-X page for more information about how to access this data and the restrictions.

There are 17 Terabytes of data in the GeoEarthscope archive from the ERS1, ERS2, Envisat, and Radarsat. Access to data requires submission of a "mini-CAT1" research proposal available here -- maps of geographic coverage are available here. Note: Much of the data requires being both gunzipped AND untarred, even though there is no .tar suffix.

WInSAR members can get access to data from ALOS PALSAR by filling out this application (click on "new user"). In the comment field where it asks for a brief description of the purpose of data use, the member needs to enter the phrase "WInSAR". Once ASF receives the data use agreement, an account is set up with access to an archive of about >500,000 scenes mostly formatted at L1.0. You can search this archive here -- it covers mostly the Americas, but limited data from other areas of the world are available too. If you aren't a WInSAR member, then join! Some data is available for immediate download from the ASF datapool. If the data you want is not in the datapool, but is from the Americas and you are a WInSAR member, you can request that data be transferred to the datapool by emailing ASF user services (uso-at-asf.alaska.edu). Data outside of the Americas not already in the datapool cannot be accessed from ASF. The complete ALOS catalog is available at the JAXA site. We recommend the use of the getSAR tool (see below) if you are downloading lots of data.

The ASF also has a large collection of SAR data from ERS, Radarsat and JERS that they downloaded within the range of their satellite dish. Some Radarsat data is available for areas all over the world -- you can search for the available data here using the geographic search. Some of the ERS and Radarsat data over the U.S. is in GeoEarthscope, but not all of it. To gain access to the data, you need to submit a short proposal detailing the type of data you need and how much. Th proposal is usually approved within a few weeks. The JERS and ERS data from ASF have special formats that won't work in conventional ROI_PAC. A script to function for the ERS data is available here, but the JERS data will not yet work. For use in ROI_PAC, the RADARSAT data should be downloaded in CEOS format.

AccessToData (last edited 2011-12-02 23:15:47 by StephanieHiggins)