Calgary Herald

TORNADO FIGHT GOES HIGH-TECH

EARLY WARNINGS KEY IN SEVERE WEATHER

- JASON VAN RASSEL CALGARY HERALD JVANRASSEL@CALGARYHER­ALD.COM

When the deadly Pine Lake tornado struck central Alberta in 2000, there was plenty of warning — the issue then was if anybody heard it.

The 12 people killed July 14, 2000, were enjoying the outdoors at the Green Acres campground, away from TV and radio bulletins that warned of severe weather and possible tornadoes 40 minutes before the twister hit.

Today, the Internet has dramatical­ly increased the number of ways authoritie­s in Alberta can warn of tornadoes and dangerous winds — and ubiquitous smartphone­s and tablets have improved the chances people will get that informatio­n, no matter where they are.

“Our reach is as good as it can get, given current technology,” said Tim Trytten of the Alberta Emergency Management Agency, which operates a provincewi­de system that send out alerts about natural disasters and other hazards across a variety of media.

The Alberta Emergency Alert system is capable of issuing bulletins that go out simultaneo­usly on 128 TV and radio stations, social media platforms such as Twitter and Facebook, and via text message to RSS feed subscriber­s.

The province launched the network, which costs $1.6 million a year to operate, in June 2011.

Despite the system’s wide reach, Trytten said changing technology means finding ways to get alerts distribute­d on new platforms as they become more common.

“Part of it is recognizin­g where the people are,” said Trytten, adding his agency is developing an app for smartphone users.

And in the case of a fast-moving, highly dangerous phenomenon like a tornado, the informatio­n also has to be timely and accurate.

For that reason, Trytten said, local authoritie­s have direct access to the alert network to issue bulletins. The provincial government’s role is to provide them with the means to do it.

“They’re the people on the ground with the eyes and the ears near that emerging event,” said Trytten.

Trytten said the element of local control combined with its vast reach makes the Alberta Emergency Alert system one of the most advanced available.

It’s an expertise learned in the wake of another deadly tornado: The 1987 Edmonton twister that killed 27 people and did hundreds of millions of dollars in damage.

Today’s alert network is a descendant of the Emergency Public Warning System, which was the first to use broadcast outlets to issue bulletins directly to the public when it was establishe­d in 1992.

Like the warning network, the system for forecastin­g tornadoes in Alberta has benefited from advances in technology.

However, a veteran forecaster who specialize­s in severe weather said tornadoes defy easy prediction.

“They’re such an intense, smallscale event,” said Bill McMurtry, an Environmen­t Canada meteorolog­ist based in Calgary.

At the time of the Pine Lake tornado, Environmen­t Canada was in the middle of a cross-country modernizat­ion that expanded the use of Doppler technology in the province.

Unlike convention­al radar, Doppler technology allows forecaster­s to see wind patterns and velocities that can indicate if a storm is capable of spawning a tornado.

Storms are the result of instabilit­y caused by warm air masses colliding with colder ones.

The added presence of wind shear — variations in wind speed and direction — can make the difference between an average storm and a more intense disturbanc­e capable of causing damage or destructio­n, McMurtry said.

Those are conditions that can exist virtually anywhere, but what makes the Prairie provinces particular­ly susceptibl­e to tornadoes is the addition of high moisture and humidity.

That may seem unlikely in landlocked Alberta, but McMurtry said a field of crops at the height of its growth cycle is capable of putting more moisture into the atmosphere than a body of water the same size.

There are an average of 10 reported tornadoes in Alberta every year, concentrat­ed mainly in the central part of the province.

“The bull’s-eye, in this province, tends to be around Red Deer,” he said.

McMurtry acknowledg­ed a relatively low number of tornadoes materializ­e compared to the number of watches and warnings issued by Environmen­t Canada, but said there’s good reason for it.

The incredible destructiv­e power of tornadoes — the Pine Lake twister packed 300 km/h winds and hurled trailers at the Green Acres campground hundreds of metres — can go some way toward explaining the frequency of alerts.

As well, McMurtry said intense, destructiv­e weather systems can quickly form and dissipate over small areas while leaving others nearby unscathed.

“Sometimes there’s a sense there are a lot of false alarms, but more often than not there’s some form of severe weather out there,” he said.

Windstorms may lack the catastroph­ic impact of tornadoes, but they are a more frequent threat in southern Alberta and bring their own dangers.

In August 2009, three-year-old Michelle Krsek was killed by a steel bundle that plummeted from a downtown Calgary building under constructi­on during a gusty storm.

The event prompted the city to implement a wind forecast and monitoring system for constructi­on sites.

Projects in the inner city and Beltline areas that are five storeys or taller are required to enrol in the program, which provides forecasts and alerts online, as well as via email and text notificati­on.

The program recently expanded to include existing buildings undertakin­g work or maintenanc­e at or above the fifth floor. Although en- rolling in the program and installing sensors isn’t mandatory for existing tall buildings, it’s a condition of receiving a building permit for having work done.

The city has also developed a smartphone app that can provide contractor­s and home builders working anywhere in the city with neighbourh­ood-specific wind data.

The app sells for $9.99, and Cliff de Jong of the city’s developmen­t and building approvals department said it’s accessed approximat­ely 150 times a week.

“We want to make it more widely used than it currently is,” he said.

On Nov. 27, 2011, a windstorm that lashed the city demonstrat­ed the monitoring system’s capabiliti­es and tested Calgary’s emergency response apparatus.

Calgary’s wind monitoring uses computer models to forecast winds up to 48 hours in advance.

The day before the storm struck — a Saturday — de Jong said the model was predicting wind speeds he hasn’t seen before or since: Up to 150 km/h at building tops.

“When I was looking at the numbers, they were jumping off the page,” he said.

Later that day, Environmen­t Canada put out a wind warning of its own.

City officials said a close working relationsh­ip with Environmen­t Canada proved vital in that case and continues to help them better predict severe weather.

“More times than not, we’ll take our (weather) informatio­n and contact Environmen­t Canada and ask them, ‘What do you see?’ ” said deputy chief Len MacCharles of the Calgary Emergency Management Agency.

As the computer models predicted, high winds arrived that Sunday, prompting CEMA to activate the city’s emergency response plan.

When the plan is set in motion, representa­tives from up to 35 local agencies — police, fire, EMS, utility companies, roads, building services and others — converge on the city’s emergency operations centre, a highly secure command hub in Crescent Heights designed to keep the city functionin­g in a disaster.

During the 2011 windstorm, authoritie­s decided to shut down the city’s downtown — a decision that proved fortuitous, considerin­g the volume of glass and debris that fell from buildings in the core.

MacCharles said keeping people from entering the inner city and trying to keep people who were already in the core indoors was made easier because the storm happened on a Sunday.

The windstorm also illustrate­s why emergency preparedne­ss relies not only on a large degree of planning, but on being able to respond to situations that can rapidly change.

CEMA has specific plans for many types of events — including tornadoes — but MacCharles said they’re meant to be flexible.

“It provides things to consider and what you may need to do,” he said.

For example, if a tornado or windstorm struck the city during a weekday in the spring, the response would have to consider the whereabout­s and safety of kids attending schools in the affected area.

Because tornadoes often strike so suddenly, MacCharles said it’s likely CEMA’s largest challenge would lie in the immediate response and recovery.

MacCharles said the response to June’s massive flooding demonstrat­ed the importance of restoring vital services, such as utilities, as quickly as possible.

“That’s how you get people and the community back on their feet,” he said.

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 ?? Leah Hennel/Calgary Herald ?? Deputy chief Len MacCharles of the Calgary Emergency Management Agency says a close relationsh­ip with Environmen­t Canada improves accuracy in predicting severe weather.
Leah Hennel/Calgary Herald Deputy chief Len MacCharles of the Calgary Emergency Management Agency says a close relationsh­ip with Environmen­t Canada improves accuracy in predicting severe weather.
 ?? Calgary Herald/Files ?? Most people were outdoors when severe weather warnings were issued 40 minutes before a massive tornado caused destructio­n on the Green Acres Campground at Pine Lake on July 14, 2000.
Calgary Herald/Files Most people were outdoors when severe weather warnings were issued 40 minutes before a massive tornado caused destructio­n on the Green Acres Campground at Pine Lake on July 14, 2000.

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