Term ‘bomb cyclone’ not alarming, says meteorologist

The use of terms like “atmospheric rivers” and “bomb cyclones” to describe weather phenomena has disappeared from scientific journals and entered the mainstream in recent years, but meteorologist Cindy Day says there’s nothing alarming about this language.

Day says such scientific language, when used properly, is necessary and can help people better prepare for the impacts of extreme weather events.

Her comments come as British Columbia’s coast braces for intense winds caused by a bomb cyclone, a non-tropical storm system caused by a rapid drop in atmospheric pressure at the center.

Environment Canada warns it could bring gusts of 120 km/h on the central and northern coasts, with winds of 100 km/h or more elsewhere on the coast and on Vancouver Island.

It says the storm could cause downed trees, travel delays and power outages, with the storm’s peak expected tonight and severe weather likely to last until Wednesday.

Day says the term “bomb cyclone” has been used by scientists for decades and describes “a low-pressure system undergoing explosive cyclogenesis,” or the creation of cyclonic air circulation.

She says terms like “bomb cyclone” and “atmospheric river” can often help paint a picture that allows people to better understand and prepare for different weather systems.

In British Columbia, an atmospheric river that originates near Hawaii has long been known as a “pineapple express.”

“So an atmospheric river — people immediately start thinking, ‘Okay, it’s a narrow strip of moving water,'” Day said.

“It gives you the feeling that this will be a steady event and there won’t be time for the ground to absorb the rain. It will continue to rain and eventually cause flooding because of that concentrated rainfall.”

In British Columbia, the government called for the creation of a scale to assess the strength of atmospheric river events in 2021, in the wake of a devastating system that caused widespread flooding and closed the Trans-Canada Highway and other major roads.

But Environment Canada said the following year that introducing such a scale for public warnings was premature.

Day noted that she had received “a lot of flak” for using the term “bomb” in connection with meteorological phenomena, with some accusing her of trying to sensationalize weather events.

“I really believe that when used in the right context, they are not alarming,” she said.

“As long as people know they are getting their information from a qualified source, and that source (or) person uses the terms correctly and doesn’t shout ‘bomb’ every time rain comes into an area, I think it will be very It is important to understand those words, to take them seriously and to know that they are based on meteorological facts, on science.”

This report by The Canadian Press was first published Nov. 19, 2024.