Wayne F. J. Evans
La Science atmosphérique
Atmospheric scientist who has worked on several space satellite missions.
"Global warming is a problem that is affecting the whole world and because the gas lifetime in the atmosphere is so long it will take a long time to deal with it. The scale of the problem in time and space is just mind-boggling."
Often one thinks of launching a satellite into space so that it can look at the stars, but Evans has turned the eyes of many satellites back down to Earth. His research interest is the atmosphere and the multitude of gases that make it up.
For his Ph.D. thesis, Evans measured the ozone layer using high altitude balloons. This research was just ahead of the curve and within a couple years, the ozone hole was discovered. Because of his earlier research and experience, Evans moved to Environment Canada to work on the STRATOPROBE project.
This was Evans first satellite mission, and the goal was to measure a range of important gases that affected the ozone layer. In fact, Evans team was the first to measure Nitric Acid in the atmosphere, and they discovered the Arctic ozone hole just a year after the Antarctic ozone hole was found.
In 2001 Evans saw another satellite with his name on it launch, when the ODIN satellite carried the University of Saskatchewan’s OSIRIS instrument into space. OSIRIS was able to measure several ozone related chemicals and help refine the data available.
After fifteen years at Environment Canada, Evans left to do research at Trent University in Peterborough. The change of workplace also shift in research focus. Evans continued to research ozone, but his focus became greenhouse gases, a topic that was rapidly beginning to heat up.
In 2003 the ACE satellite from the University of Waterloo rocketed into space, and Evans was able to get data from the satellite. Unlike previous satellites, ACE had the capability to measure over a thousand different chemicals in the atmosphere.
Thus, Evans began to study what he calls “his most important work”, radiation forcing. Radiation (for example, light and heat) come from the Sun, trickle through the atmosphere, and heat up the Earth before returning into space. Greenhouse gases have insulated the atmosphere so less heat escapes, in essence, throwing off the radiation balancing act.
How much it has been thrown out of whack, is what Evans has tried to find out. By monitoring and measuring atmospheric chemicals, he’s been able to determine how much of an effect chemicals like methane or jet contrails are having on the overall temperature. “The IPCC [Intergovernmental Panel on Climate Change] has been using radiation forcing as their scientific yard stick to tell you how powerful gases are in comparison to carbon dioxide. I’ve been measuring that quantity, whereas they’ve been calculating it using a model.”
By measuring atmospheric chemicals, Evans has found out that the IPCC’s models are actually slightly wrong compared to reality. For example, they predict that methane is 25 times more powerful that carbon dioxide as a greenhouse gas. Evans has found it is actually 17-18 times more powerful, a difference of around 20%.
Evans other works has focused on jet contrails. “Cirrus clouds cause a change in the radiation balance, and jet contrails are artificial cirrus clouds,” said Evans. “So plane flights are altering cloud cover and the radiation balance.”
By Graeme Stemp-Morlock
Global warming is a problem that is going to take us hundreds of years to deal with, and there’s gonna be several science career lifetimes to deal with this problem. We are going to need all kinds of careers, from biologists seeing what happens to plants to engineers developing carbon sequestration.