Remote Sensing, Not Remote Viewing

When I mentioned to friends that I was going to be taking a class in remote sensing this quarter, many were baffled. “Wait… Benny… WHAT?!” they asked. I understood immediately what the confusion was. No, I assured them, I don’t think I’ve become psychic.

Remote viewing is the term used for the belief that people can use clairvoyance to perceive and learn about places, objects, or people that they cannot sense directly. It is a psudoscientific belief and process with absolutely no evidence to support it and flies in the face of all known science. Despite this, research into it was invested in by militaries around the world, including the United States Army. This is NOT what I am studying in college.

On the other hand, remote sensing is the process of using imagery taken by satellites or from aircraft to study the surface of a world. It is an area of the science of geographic information systems, and a tool commonly used in geography, environmental science, Earth systems science, and other fields. In most cases, we mean the study of the surface of Earth, though many of the same techniques are used to study other bodies as well. This kind of work goes back to taking photos from balloons in the first World War, and continues today in projects like the USA’s Landsat satellites.

The taking of images isn’t the whole field, though. Remote sensing includes the process of using those images to discover things about the locations imaged. Most satellite systems like Landsat take images in specific spectral bands, including visible colors and several wavelengths in infrared. Since different surfaces reflect or emit different wavelengths of light these separate bands can allow people to learn different things about the surfaces that have been imaged, such as differentiating locations of vegetation or rock, visualizing the temperature of water, and more.

I’m definitely new to remote sensing, since this is my first class in it, but I’m enjoying what I’m learning. We use a geographic information system program called ArcMap (Part of the ArcGIS system) to do most of our work, and work with images from the US Landsat system.

For one of our projects I created a visualization of the heat plumes in the ocean from the Fukushima Daiichi nuclear plants before the disaster there in 2011. For this I used the thermal infrared band in an image from 2001 acquired by the satellite Landsat 7. I’m pretty proud of how it came out, although it’s student work and not perfect.

Heat plumes at Fukushima Daiichi Nuclear Power Plant before the tsunami.
Heat plumes at Fukushima Daiichi Nuclear Power Plant before the tsunami.

The full size version can be seen here.

I also did a land cover analysis of the Chicago area. This involves training the system to identify different types of land cover (like agriculture, various densities of residential areas, “urban grassland” which actually means golf courses, etc) by selecting specific locations that are known to be that type of land cover. Then ArcMap can fill in the rest of the image, showing which areas have similar spectral values in the various bands in the image. Mine isn’t perfect (it shows a lot of roadways as being high density residential for some reason) but it was an excellent learning experience.

Land cover analysis of Chicago
Land cover analysis of Chicago

The full size version can be seen here.

So, remember – Remote viewing is psudoscience trying to view the world from a distance. Remote sensing is super fun science succeeding in viewing the world from a distance.

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Remote Sensing, Not Remote Viewing
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