Living in Canada means putting up with severe weather conditions: blizzards, white-outs, freezing rain and ice storms in the winter, and thunderstorms, hail, floods and tornadoes in the summer. But until recently, weather forecasting was vague and unreliable, making it difficult to prepare in advance

for severe weather conditions. Environment Canada is hoping to change this, now that it has completed a cross-country network of 31 Doppler radars. This technology is expected to make weather forecasting more accurate, providing more timely weather warnings for 98 per cent of Canadians.

Radars measure precipitation and help weather forecasters predict where severe weather is brewing. The latest technology evolving in this area is Doppler, which allows for the detection of high-impact weather from as far away as 250 km. Satellites only give you a look at what’s happening from a great distance, says Steve Lapczak, director of the national radar project with Environment Canada. Doppler radars, on the other hand, can show you if weather is moving toward you or away from you. “”The ice storm is a good example — you can see the cold air coming down the St. Lawrence Valley and the warm air going off in the opposite direction,”” he says.

Stormy economics

The $34.9 million project kicked off in 1997. But Doppler technology isn’t new; it was used for the first time at a King City, Ont., installation in the mid-1980s. In 1987, a tornado ripped through a trailer park in Edmonton, killing 27 people. Immediately afterwards, a Doppler radar was installed in Alberta’s capital. By the early 1990s, there were four Doppler radars in existence, with plans to add an additional four or five across the country. But then budget cuts hit. “”We just couldn’t move — things were put on hold from about ’94 through ’97. We were downsizing severely, we were closing weather offices,”” says Lapczak. “”While that was happening, management said, ‘This stuff is good, our network is sparse, we’ve got holes all over the country.'”” It undertook a research project to analyze severe weather across the country and decided to move toward Doppler radar.

In 1997, a group of in-house engineers took on the project, adding new radars, converting existing ones to Doppler, and shuffling the network around to provide maximum coverage. Then, software had to be designed to make sense of the data provided by the radars. “”If you can’t get the information to the forecaster, then it’s useless,”” says Lapczak.

By using a computer to analyze all of the radars simultaneously and pull patterns out of the data, forecasters have access to more information about each storm as it occurs. The software goes a step further by analyzing and classifying “”cells,”” which means it quantifies the severity of weather within a “”cell”” or specific region. If the software senses that something is out of kilter, it starts sending e-mails to technicians.

“”There might be 80 or 90 (storms) on a bad day at one time, and the decision for the forecaster is which one is severe, which one should he put out a warning for,”” says Paul Joe, a research scientist whose team developed the software. But the software isn’t perfect, he adds, and they still rely on the human ability to conceptualize in order to make decisions.

Winds of change

This is a completely new way of doing things, says Lapczak, so there was some resistance at first. “”It became a case of training the meteorologists because they’d never seen this stuff before,”” he says, “”and that was a big job.””

Now that the last Doppler radar has been put in place, federal, provincial and municipal emergency measure organizations will have more time to respond to severe weather conditions, and meteorologists will be able to provide better forecasts in both urban and rural areas. Daily weather forecasts, severe weather warnings, real-time radar imagery and air quality forecasts are available to the public at www.weatheroffice.ec.gc.ca. Weather forecasters, however, receive much more detailed information in order to make more accurate predictions about severe weather conditions.

Environment Canada is making its technology available to a European consortium, called NinJO, which is working on a much more elaborate weather-forecasting project that includes not only Doppler radar, but satellite, lightning and other types of meteorological data.

“”Most people are interested in the concepts we develop — the ability to sort and categorize every storm and access the information in a numerical or graphical form,”” says Joe. The team sparked interest in its work during the Sydney Olympics; it’s now planning to demonstrate the technology at the Beijing Olympics in 2008. “”The future is to be highly precise both in space and time, so we would give you information accurate to two minutes or five minutes and very specific to a location like the Olympic Stadium,”” he says. “”We can do forecasting for those specific venues.””

Like all technology, it’s continuing to evolve. Researchers are already working on a more sophisticated radar system using dual polarization, which can differentiate between precipitation types such as rain and hail. This is expected to result in even better detection of severe weather; the first installation is expected to be operational in King City at press time.

“”The software will have to change to that,”” says Joe, “”but my gut feeling is that’s going to change very quickly.””

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