AV Landsat Viewer

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About the AmericaView Landsat Viewer

Background

The AmericaView Landsat Viewer is a collaborative project involving WisconsinView and the DLT development team that leverages RealEarth and EODN to provide visualization of landsat imagery in near-real time.

The project centers around RealEarth developed at the Space Science Engineering Center (SSEC) at the University of Wisconsin, Madison (WisconsinView). In addition to automating the tedious process of downloading and preprocessing Landsat data, RealEarth allows Landsat data to be combined with more traditional data sets used by atmostpheric scientists to provide better insight into weather patterns and other atmosheric phenomina.

Operation

AVMSS Landsat Viewer tightly integrates RealEarth and EODN to provide access to Landsat8 data as quickly as possible after acquisition. By automating  the process of downloading, processing and staging new scenes in RealEarth, users are able to quickly evaluate scenes for suitablility for a wide variety of time-dependent  applications.  In addition, RealEarth allows Landsat data to be layered with other atmospheric and meterological data sets exposing new and inovative applications.  

Data Staging

(A) The EODN Harvester, a part of the DLT software suite, continually monitors USGS EROS Landsat 8 archives and automatically retrieves new scenes using the USGS Inventory Service Machine-to-Machine (M2M) API.  EODN Harvester then uploads scenes to EODN and store the resulting exNode in UNIS. ExNodes are stored in a UNIS directory structure by Path/Row and date and can be access by users and applications using a variety of search algorythms.

 

 

AV NAIP Viewer Illustration 

RealEarth Processing

(1) eodn_feed, part of the dlt-tools package, listens for new landsat scenes on EODN and automatically downloads them to AVMSS. A custom script feeds the resulting images to RealEarth where an automated ingest process uses them to create WMS image tiles.

User Experience

New Landsat scenes appear in the RealEarth viewer as soon as they become available. This completely automated process insures that the latest data is always available as quicly as possible. RealEarth permits users visual access to scenes without having to download and process the raw files and EODN's intellegent data movement and multi-stream transfer protocol ensures minimal latency between acquisition and presentation. Together these these technologies provide an important capability not available with other systems.