Subject(s): air turbulence
Title: Types Of Turbulence
OK, you're in a plane and the captain comes on the PA and says buckle up, we're expecting some heavy turbulence up ahead. Hi, I'm Dave Thurlow for The Weather Notebook and today we're going to learn about turbulence from Larry Cornman at the National Center for Atmospheric Research. Here he describes the three ways that smooth airplane rides become bumpy. First, Convective Turbulence.
Larry: "Convective turbulence is turbulence that's created by a thunderstorm and the source of the turbulence there is typically the rapid up and down motion of the air parcels inside the thunderstorm. What's interesting about convective turbulence is that you can get very severe turbulence not only inside the cloud but outside the cloud."
The second is called Mountain-Induced turbulence. This is when air flows across a mountain range and makes a wave in the air flow above. It's just like a wave in a stream flowing over a rock.
Larry: "When you have a very low speed of the water it'll flow right around the rock and not get very disturbed. But, as you increase, either the size of the rock and also the speed of the water all of a sudden you get waves generating and they break like waves on the beach"
Now if these waves get really big, up to 35,000 feet, they hit the jet stream and produce the third kind of turbulence, called jet stream turbulence.
Larry: "You need a strong enough flow over the mountains to get these waves generated and the jet stream is a good source."
It's also where a lot of planes fly. So, describing these 3 processes will hopefully lead to better turbulence forecasting and advanced warnings to pilots.
The Weather Notebook is a production of the Mount Washington Observatory in North Conway NH.