When a cold northwest wind blows a winter storm into Ontario, Dr. David Hudak takes to the skies in a research aircraft, collecting data about the clouds that are creating havoc below.
The stormy flights are part of Hudak's job as a research scientist with Environment Canada studying clouds and other weather-related phenomena. But soon these flights will have another aim: to check the accuracy of data collected over Canada by NASA's CloudSat, the new Earth-orbiting satellite, as it begins its comprehensive study of clouds. It is set to launch in 2006.
This will be the first satellite to profile clouds in three dimensions. CloudSat will also have a near-polar orbit, so for the first time we'll be able to study the all the clouds over Canada," says Hudak, who is the project's Canadian co-principal investigator.
Hudak will help validate the satellite data on Canada—a project funded by the Canadian Space Agency. He will compare data from CloudSat with information collected by Environment Canada's existing radar and forecasting network, a state-of-the art field site, and the National Research Council's cloud physics research aircraft. "When CloudSat is over southwestern Ontario, we'll be flying under it every chance we get."
To help us better understand how clouds affect climate, and use that knowledge to improve projections of climate change, CloudSat will gather new information on the structure and volume of clouds, as well as the amount of water and ice they contain, thanks to the Canadian contribution of millimetre-wavelength radar.
"This information will increase our understanding of how precipitation is formed," says Hudak. "And it will improve the numerical climate models so projections will be more accurate."
It was the chance to see nature's beauty and fury up close that first drew him to this field. Trained as a weather forecaster, Hudak then earned a doctorate in physics from the University of Toronto in radar meteorology and cloud physics. Today he works for the Science and Technology Branch of Environment Canada. During his 30-year career in atmospheric science, he has been involved in research projects around the world.
"I've taken part in studies of winter storms in Newfoundland, the monsoons in southeast Asia, blizzards and storms in the High Arctic, and weather modification projects in Africa," says Hudak. "I spent six years trying to make rain in Africa by seeding the clouds and it has been a terrific learning experience. One way to know if you understand weather is to see if you can change it."