Remote Sensing

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Revision as of 07:28, 16 July 2022 by Bmueller (talk | contribs) (→‎SAR)
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Remote Sensing is a generic term for types of satellite or high-altitude aviation imagery that contains bands outside of the visual spectrum, or uses a novel method of capturing images that the human eye would otherwise be unable to see.

"Where we're going, we won't need eyes to see" - Sam Neill, Event Horizon

Sources

As with most imagery, remote sensing data tends to fall into one of two categories: freely available and low resolution (to a technical user), or high quality and easy to use but absurdly expensive. If you have to ask how expensive, odds are you simply don't have the money.[1] This is all to assume that you can even open the data and use it- the software to do so is either proprietary, clunky, or both.[Citation NOT needed but provided anyways][2]

However, as time goes on, more and more is slowly becoming available.[3] (Todo: if anyone can figure out the prices for various providers, here would be a good place to put them)

Free

  • NASA (EarthExplorer, various)
  • ESA (Sentinel-1)

  • Capella (SAR)
  • Hawkeye 360
  • ICEYE

Types

NIR (Near-Infrared)

Many satellite imagery providers (e.g. Planet 0.5m) include NIR bands. NIR puts particular emphasis on plants and vegetation, and can be used with other bands to detect regions of ice, vegetation, fires, etc. A common method of analysis is to simply use the imagery as you would optical, but replace the "red" band (e.g. in Qgis) with the NIR data.

SAR (Synthetic Aperture Radar)

todo

Other

todo: talk about how you can detect ice, snow, fire, etc. by doing veeery specific band math in e.g. qgis. Maybe write a guide on it?

References