Tuesday, November 20, 2012

Australian Floods Mapped

Earlier this week Geosciece Australia released a proof of concept web service displaying trial study areas of historical flood mapping derived from satellite imagery. It contains one low resolution national layer and several study areas in high resolution. The national layer displays a 500x500m grid summarising how often water was observed in specific location by the MODIS sensor from 2000 to 2012. A more detailed information, derived from Landsat-5 and mapped into a 25x25m grid is available for:

  • Condamine River system between Condamine and Chinchilla, Queensland
  • Northwest Victorian rivers between Shepparton and Kerang
  • North Queensland rivers, near Normanton

Over the next two years this service will be developed into a nationwide portal to ultimately provide data on flooding which has been observed by satellite across Australia since 1987.

The information has some limitations as not all foods can be detected by satellites since observation of the Earth by satellite depends on clear skies and satellites have specific, scheduled observation times. Nevertheless, it’s a first attempt to map floods consistently across the entire continent and the service will provide valuable insights into flood patterns and food extents.

Wednesday, November 7, 2012

Google unlocks Landsat archives

It took Google 2 ½ years to convert 40 years of Landsat imagery from tapes stored in USGS archives to the cloud. Two petabytes of data in total. Now all this data is made available to researchers and non-profit organisation for comparison and number-crunching through the Google Earth Engine tool under the Google Earth Outreach program.

There is a great expectation that free access to data and significant computational capability will lead to a surge in public benefit maps coming out of Australia. Organisations that have already partnered with Google to access a suite of GIS products and learn how to use them for free include the Australian Wildlife Conservancy (AWC) and the Great Barrier Reef Marine Park Authority (GBRMPA).

Despite numerous attempts over the years to open up the vaults of valuable satellite data to academics, research institutions and individuals it took a determined private company to make it all possible. A good example of public-private collaboration that is probably a sign of things to come. This is a side of Google that we all would like to hear about more often.

More free data: Satellite Imagery Catalogue