Device studies wind at the edge of space
N.B. prof. William Ward's tool will help track climate change
A scientist at the University of New Brunswick has found a way to study wind blowing at the edge of space, which could help monitor the effects of climate change.
While wind is easy to detect on the ground, it gets harder 90 kilometres high in the sky. William Ward created a method to measure wind speeds of up to 200 km/h in the upper atmosphere.
Pressure waves disturb the airglow produced by solar radiation in the upper atmosphere. Ward has built detectors to observe them.
"This is sort of a bore event, sort of a bit like the Petitcodiac River except that it occurs at 90 kilometres up," Ward said.
"We're trying to observe waves in the atmosphere and figure out how large they are, whether they're breaking and then how they break. And the other aspect is that when they break, they create this large-scale flow from the pole to the pole which affects the circulation in that region of the atmosphere."
Optical radar gun
Being able to see the patterns in the upper atmosphere now could help track the effects of climate change in the future.
Ward has developed a box full of lenses called an interferometer. It works like an optical radar gun.
"The waves go up and they hit this airglow layer and they cause changes in the density of the air which show up as changes in the airglow. And the airglow is a natural, emitting layer, sort of chemiluminescence that occurs all the time in the atmosphere," he said.
"So we almost use it as a TV screen to see what's going on when these waves reach their big amplitudes and start breaking."
Network of sensors
One of Ward's devices is being used at the Polar Environment Atmostpheric Research Lab on Ellesmere Island to watch the Arctic sky.
Ward hopes to create a network of such sensors, which would open a new window into atmospheric observations.
"We're on the cutting edge of being able to make images of winds associated with these waves and this will really be the first time that's been done in the world."