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Diving Deeper Shorts: Remote Sensing

Episode 25 (July 11, 2013)

HOST: Today's Diving Deeper Shorts explores the science of remote sensing. In just a few minutes, we will explore what remote sensing is, some of the benefits, and specifically how remote sensing supports emergency response efforts. Follow along as we revisit a past episode where we talked with Chris Parrish from NOAA's National Geodetic Survey.

Let's listen in.

HOST: Chris, is there any additional explanation that you can give us on remote sensing?

CHRIS PARRISH: When I explain remote sensing to people, I'll typically put it in terms of examples of people that I actually know and work with, who work in the field. So for example, I have one colleague who works for a large commercial satellite imagery company, and that company operates Earth observation satellites, they supply imagery to the U.S. government and military as well as to other commercial firms. I also work with a lot of people, including several of my NOAA coworkers, who are involved in collecting, processing, analyzing remotely sensed data collected from aircraft so that could include aerial imagery or light detection and ranging, lidar data, that's used for topographic mapping, and those data will be used for just a huge variety of applications. It could be anything from forestry to agriculture to military applications, ecosystem mapping and monitoring, emergency response, climate change for example. And in our office, we typically use the data for coastal mapping, particularly mapping the national shoreline.

HOST: What are some of the real benefits of remote sensing?

CHRIS PARRISH: Kate, in answering the question of what the benefits of remote sensing are, I think it's kind of helpful to go back to when people first started putting cameras on airplanes or even before that, going back to the 1800s when people were putting cameras on balloons or even on kites, and to ask the question, what was the motivation for doing that? And a lot of times the motivation was simply that people wanted to be able to map a relatively large area a lot more efficiently and probably a lot more cost effectively than if they had to do it through a ground survey. And I think that today, a lot of those same motivating factors often hold true.

And then just to throw in a related benefit, a lot of times, remote sensing is the only feasible way to collect data in areas that might be dangerous or in some cases, really impossible to put people on the ground to collect the data. And you can imagine a really remote area in Alaska as maybe an example of that.

HOST: How does remote sensing support emergency response perhaps following something like a hurricane?

CHRIS PARRISH: Kate, our office, NOAA NGS is pretty frequently called on to respond to hurricanes and other disasters. Typically what we'll do is we'll try to fly the impacted areas as soon after an event as possible. So one of the really common goals is to be able to acquire imagery and have it online for people to download within 24 hours of a hurricane making landfall and we'll try to provide geo-referenced aerial imagery, which means that each image pixel is associated with a particular set of map coordinates, a latitude/longitude for example, and the way that's used - first responders can use it in looking at what the most heavily impacted areas are, sometimes property owners can use it if they've been displaced and they want to know what's going on with their property, was it damaged.

HOST: That's all for today's Diving Deeper Shorts. Want to learn more? Go to and click on the October 2010 podcast archive to listen to the full episode. Diving Deeper is back in two weeks - see you soon!