Less than a year after Hurricane Fiona brought damaging winds and sea level surge to Nova Scotia, the province has endured large suburban and rural wildfires and catastrophic floods.
Environment Canada Canadian Hurricane Centre Sept 23 2022
In June 2023, Nia Williams reporting for Reuters asked Ellen Whitman, a research scientist with the Canadian Forest Service, about the role of climate change in providing conditions for wildfires.
there is also speculation that trees felled during Hurricane Fiona, which hit Atlantic Canada in September 2022, or killed by an infestation of forest pests may be providing more fuel than usual for wildfires, but that theory requires further investigation.
Whitman said it is difficult to determine the impact of climate change on a single fire season, but Atlantic Canada has been much hotter than usual and scientists expect temperatures in the region to continue to rise in coming years.
For coastal regions climate change is expected to bring more rain, which should reduce the risk of wildfires, but a warmer atmosphere is more efficient at pulling moisture out of soils, a factor that increases fire risk.
Widespread spring fires across the whole of Canada are also unusual, and research shows fire seasons across North America are getting longer.
(Williams, 2023)
Mark Hodgins, reporting for City News, writes that according to Environment Canada Meteorologist Bob Robichaud torrential rain in parts of Nova Scotia has shattered records. He said 200mm of rain fell in many areas and some saw up to 250mm, most of which came down over several hours on Friday. There were unconfirmed reports of up to 300mm falling in some areas.
“It certainly was a tremendous storm,” Robichaud said. “It was a record-shattering storm with the amount of rain we got in a short period of time.”
A rainfall warning had been issued on Friday calling for up to 80mm of rain, and said a tropical stream of moisture was responsible for the forecast.
“When you have these tropical moisture feeds, there’s just so much of that moisture to be wrung out it creates very intense rainfall rates,” Robichaud explained. “We’ve seen set-ups like this before, but none in recent memory have stayed over the same area for an extended period of time which is what we saw on Friday.”
The storm brought rain to Nova Scotia in amounts not seen in more than 50 years. In 1971, Hurricane Beth dumped more than 270mm on some areas and led to significant flooding.
“The one-in-100 year rainfall is 172mm, so certainly with areas that have seen more than that it’s more than a one-in-100 year event, so a very rare event for sure.”
In a briefing on Saturday, Halifax Mayor Mike Savage said recent events in Nova Scotia, including Hurricane Fiona, recent wildfires and now flooding makes it clear climate change is having an impact in Nova Scotia.
Meteorologist Bob Robichaud agrees.
“One of the stronger signals from climate change is that these events will be on the rise from climate change,” he explained. “The warmer the atmosphere, the more it can hold water. So in a warmer atmosphere, we’re going to get more of these types of events happen more frequently. That’s certainly what the data is showing.”
Environment Canada is forecasting a dry spell for the next few days in terms of precipitation, although it’s still expected to be humid into this week. (Hodgins, 2023)
Residents of Nova Scotia have experienced a sequence of disastrous events that are aggravated and intensified by increasing global temperature to energize hurricanes, dry forest fuel, and increase water capacity in rain storms as long predicted by climate scientists.
Now politicians must immediately prepare mitigation and adaptation strategies to address the increasing frequency of these wind, fire, and flood events also predicted by climate science.
References
Hodgins, M. (2023, July 23). Rain storm shatters records in N.S., called a "one-in-100 year event". CityNews Halifax. Retrieved July 24, 2023, from https://halifax.citynews.ca/2023/07/23/rain-storm-shatters-records-in-n-s-called-a-one-in-100-year-event/
Williams, N. (2023, June 2). Where are the Canada wildfires and are they under control? Reuters. Retrieved July 24, 2023, from https://www.reuters.com/world/americas/why-are-wildfires-raging-canadas-eastern-nova-scotia-province-2023-06-02/
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