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What We're Measuring

Images to Land Cover

a quick remote sensing primer
understanding 30-meter resolution
images to land cover
what we mean by developed
pixels vs. parcels
land cover and change categories

Computer programs and human expertise then turn the database/image into a land cover map. Land cover is what’s on the surface of the earth (forest), as opposed to land use, which is what is planned, practiced or permitted (park, wildlife sanctuary).

While the image itself is useful and instructive, it is still a picture. The resultant land cover data, however, can be quantified to show overall land cover patterns. To the right are examples from Hartford.

 

Satellite Image (Hartford)

 

Land Cover Map
(Hartford)

The pictures below summarize the process.

We have zoomed way in on a Landsat TM image (#1) so that each individual pixel is visible. Each pixel covers a 30 meter (100 foot) square on the ground.

1

 
 
 

For illustration purposes, a high resolution image (#2) is shown of the same area overlain with a 30m grid. The grid represents the size of the pixels in the Landsat image (#1).

2

 
 
 

Computer algorithms are used to classify each pixel into a land cover class based on the most prevalent spectral signature (#3).

3

 
 
 

The result is a land cover map (#4).

4

 

What We're Measuring Connecticut's Changing Landscape
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