Share

Montreal Fireball: Spectacular Flash Explained

By: Marc Lallanilla
Published: November 6, 2013

A massive fireball roared through a section of Montreal last Friday, Nov. 1, sparking worldwide interest after a dramatic amateur video of the event went viral.

The fireball burned along an overhead utility line shortly after the Montreal area was battered by an intense windstorm that toppled trees and caused region-wide power outages.

Huw Griffiths — a resident of Lachine, the borough of Montreal where the fireball was spotted — captured video of the spectacular flash. It was the second such event to occur that evening, which is why Griffiths was ready to record the incident, the Montreal Gazette reports. But what, exactly, did Griffiths witness? (Electric Earth: Stunning Images of Lightning)

"This is a high-impedance arcing fault," said Massoud Amin, a senior member of the Institute of Electrical and Electronics Engineers (IEEE) and director of the University of Minnesota's Technological Leadership Institute. "It's a release of energy caused by an electrical arc."

(MORE: Midwest Meteor Lights Up Skies)

The bright light and intense heat from an arcing fault are referred to as an arc flash. The phenomenon is similar to what happens in a lightning strike or, on a much smaller scale, the static electricity created when you walk across carpet and touch a metal doorknob: An electrical charge is diverted from one source and moves through the air to another surface.

"Electric arcs, which are similar to lightning, occur when a number of conditions are met — for example, humid weather, a branch touching a line, etc.," said Patrice Lavoie, a spokeswoman for electric utility Hydro-Québec.

"From what we can see in the video, the electric arc moves along the wires until it reaches a transformer on a distribution pole," Lavoie told LiveScience in an email. "The electric arc trips the circuit breaker — a protection device — causing the power outage in the neighborhood."

Explosive energy released

When an arc flash occurs on industrial equipment, the release of energy can be tremendous: According to a report from General Electric, temperatures can reach as high as 35,000 degrees Fahrenheit (19,400 degrees Celsius), hot enough to vaporize solid steel. The light emanating from an explosive arc blast is so bright it can cause permanent blindness.

Indeed, Griffiths had to seek shelter when the arc flash moved down his tree-lined street. The arc flash was "emanating an extreme amount of heat that essentially forced us back inside, because it was so, so, so hot," he said in his video.

Estimates vary widely, but Chicago-based research firm CapSchell has determined that arc-flash accidents kill or injure five to 10 U.S. workers every day. However, Amin cautions that such estimates may be high and should be viewed with some skepticism. Nonetheless, the costs of an arc blast and the resulting health care expenses and legal fees can add up to "millions of dollars per incident," Amin told Live Science.

'Smart grid' upgrades needed

Though they're rarely captured on video, incidents like the arc flash that moved through Lachine aren't uncommon. "It's not an isolated phenomenon," Amin said, adding that this and other events — including Hurricane Sandy — provide compelling evidence that aging electrical infrastructure is in serious need of modernization.

"We take our electrical power network for granted," Amin said, "even though it underpins our economy and our quality of life." Amin has repeatedly called for increased U.S. investment in "smart grid" electrical technologies with greater resilience and reliability, including "self-healing" abilities in the event of a power disruption.

Original article on LiveScience.

Images: Red Sprite Lightning Revealed in Stunning Photos
Video Album: Fireballs Streak Across Earth's Springtime Skies
Strange & Shining: Gallery of Mysterious Night Lights

Copyright 2013 LiveScience, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

MORE: NASA Meteor and Fireball

This is a composite, false-color image that combines meteor fall from various meteor showers (Orionids, Perseids, Geminids) from 2009-2011. All images are based on grey-scale images provided by the Meteoroid Environment Office at NASA's Marshall Space Flight Center in Huntsville, Ala. (NASA)


Featured Blogs

March 2014 Global Weather Extremes Summary

By Christopher C. Burt
April 15, 2014

March featured a number of anomalous extreme weather events such as the floods in portions of Egypt and New Zealand, a freak hailstorm in Asmara, Eritrea, record warmth in much of Europe, severe cold and snow in the eastern half of the U.S. and heavy rainfall in the Pacific Northwest that culminated in a deadly landslide in Washington. Preliminary data from NASA indicates that globally (land-ocean temperature index), it was the 4th warmest March on record (since 1880).

Wunderground Launches Major Site Redesign and New Logo

By Dr. Jeff Masters
April 15, 2014

We are transitioning to a completely new logo, as part of a site-wide redesign aimed at furthering our mission of unlocking and sharing vast amounts of weather data with as many people as possible using the latest digital technologies, in a way that is visually appealing and engaging. We kept the colors and vibrancy of the rainbow but replaced the rainbow shape with the letters "WU"; a raindrop over the "U" represents rain falling into a rain gauge, a nod to our incredible Personal Weather Station (PWS) community (34,000 strong!)

Polar Vortex, Global Warming, and Cold Weather

By Stu Ostro
January 10, 2014

Some thoughts about the recent viral meme(s).

Just in time for the Holidays! Wundermap has a new layer: Precip Start Time!

By Shaun Tanner
December 23, 2013

The Weather Underground elves have been hard at work developing a brand new layer for the WunderMap and they made their deadline. Enjoy the newest addition to the WunderMap. Also remember to give us your feedback!

What the 5th IPCC Assessment Doesn't Include

By Angela Fritz
September 27, 2013

Melting permafrost has the potential to release an additional 1.5 trillion tons of carbon into the atmosphere, and could increase our global average temperature by 1.5°F in addition to our day-to-day human emissions. However, this effect is not included in the IPCC report issued Friday morning, which means the estimates of how Earth's climate will change are likely on the conservative side.

Astronomical VS. Meteorological Winter

By Tom Niziol
March 1, 2013