Archive

Posts Tagged ‘ESA’

New LandViewer Tool for Quickly Finding and Analyzing Satellite Imagery

May 7, 2017 2 comments

The LandViewer tool and data portal quickly and painlessly allows you to browse and access satellite imagery for the planet.  The tool, developed by the Earth Observing System Inc.’s Max Polyakov, currently features Landsat 8 and Sentinel 2 imagery with more image sets soon to arrive.  Landsat 8 carries two instruments: The Operational Land Imager (OLI) sensor includes refined heritage bands, along with three new bands: a deep blue band for coastal/aerosol studies, a shortwave infrared band for cirrus detection, and a Quality Assessment band. The Thermal Infrared Sensor (TIRS) provides two thermal bands. Sentinel 2 is an Earth observation mission developed by the ESA as part of the Copernicus Programme to perform terrestrial observations in support of services such as forest monitoring, land cover changes detection, and natural disaster management.

Using the LandViewer tool, you can quickly zoom on an interactive web map to your area of interest.  You can filter on geography and time, including cloudiness, sun angle, and other parameters. At the time of this writing, 18 filters such as Atmospheric Removal, Panchromatic, NDVI, Thermal Infrared, False Color, and more, are available so that you can obtain the band combinations most suitable to your analysis in the areas of agriculture, geology, or other applications. A very helpful image interpretation screen is available to help you choose the combination that are best for your analysis goals.  You can do some contrast stretching in the web tool itself.  Then after signing in to the site, you can download the images in GeoTIF for further analysis using your favorite GIS tools.

The tool was also reviewed on the Geoawesomeness web site, and I wholeheartedly agree with their sentiments expressed–this is one of the most useful and fastest satellite image portals I have used. It is useful for research but also, given its ease of use, can even be used effectively to teach concepts of remote sensing.  Give it a try and let us know in the comments section what you think.

landsat_viewer.JPG

Landsat scenes with band combinations possible for an area on the southwest side of Costa Rica.

 

Advertisements

Sentinel-2A: ESA’s latest satellite launched

July 6, 2015 1 comment

The European Space Agency (ESA) recently launched their latest environmental monitoring satellite, Sentinel-2A, adding high-resolution optical imaging capability to the radar imagery provided by the first satellite in the Copernicus fleet, Sentinel-1A. Tasked with combining wide swaths and short revisit times (5-day cycle), Sentinel-2A will monitor land and vegetation change to deliver a range of data products including land cover maps and indices for a number bio-geophysical variables. Although the commissioning phase will last for about three months, Sentinel-2A has already recorded its first images.

Sentinel-2A's first image: Po Valley - NW Italy/Sth France. 27 June 2015

Sentinel-2A’s first image: Po Valley – NW Italy/Sth France. 27 June 2015

Once operational, Sentinel-2A’s imagery will be hosted on the Sentinels Scientific Data Hub, which will be upgraded shortly to accommodate the new satellite. The data will be available on a ‘free and open’ basis to any users registered with the data hub. Although the data will be made publicly available, they will not be in the public domain and remain the intellectual property of Copernicus Programme. However, subject to the ESA’s terms and conditions, users are free to user, alter, modify, publish and distribute the data. Judging by the first data samples, Sentinel-2A’s imagery will provide an invaluable resource for global environmental monitoring.