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One of the tools pilots will soon be using to avoid invisible clear air turbulence looks at the movement of tiny particles in the atmosphere ahead. Hi, I'm Dave Thurlow from the Mount Washington Observatory and this is The Weather Notebook. The sensing device being tested is is called LiDAR. Here's researcher Larry Cornman from the National Center for Atmospheric Research in Boulder Colorado.

Larry: "Radar uses radio wavelengths whereas the LiDAR is using light wavelengths much smaller wavelengths -- So that's a device that can be used to see the turbulence in clear air."

There are problems with the LiDAR though. First of all, it needs enough dust or aerosol particles in the air to reflect off of and you don't always have that. Secondly, the device needs to see out to nearly 15 km ahead of the plane in order to give the pilot enough warning time to steer clear of the turbulence. Larry: "Now certainly you can build devices that will do that but whether they're going to be small enough and light enough and cheap enough to put on a commercial aircraft is another problem."

And also, the software needs to be developed that takes the information from the LiDAR and converts it to make sense to the pilot. Although a lot of work still needs to be done, Larry is hopeful LiDAR devices will be on board aircraft in 3-5 years, making flying safer and less bumpy.

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