When it comes to climate change, there is a well-understood extreme that will affect humans in the coming decades: heat.
Scientists know that climate change will see an increase in the frequency or intensity of hurricanes, droughts, floods and heat waves. But when it comes to heat waves in particular, they have already been seen around the world with deadly consequences. according to A recent study published in The Lancet, more than five million deaths annually between 2000 and 2019 were related to “non-ideal temperatures”, with nearly 500,000 of these deaths related to heat.
While many of these deaths occur in tropical countries, heat waves are beginning to affect the northern climate.
during the The heat wave that betrayed British Columbia at the end of June and into the first week of July, killed more than 800 people (as of this writing) in the province. For comparison, in the same period last year, there were 232 deaths, according to BC Coroners Chief Medical Officer Dr. Gatinder Bidwan. The Office of Forensic Medicine continues to investigate all deaths in order to determine the exact number of heat-related deaths.
While we know that daytime temperatures are rising, in some areas – particularly in parts of Ontario and Quebec – At night, temperatures rise faster.
Those warmer nights mean our bodies don’t have any time to cool off. For people with health problems such as heart disease or asthma, for example, this can be a major problem and potentially fatal.
“Our bodies are not designed to withstand environmental temperatures above 30,” Bedouin said. “If you think about it, what happens to the air conditioning unit? When you stress it, it builds up with a lot of ice outside and then stops working. And that’s a great analogy in some ways to what happens to our bodies. With extreme heat, we find it really hard to do The usual symmetric kind of mechanisms and protocols that happen in our bodies.”
Watch | How can we better prepare our homes and buildings for rising temperatures?
The heat wave that affected the Pacific Northwest was very unusual – it occurs once every 1,000 years, according to a Latest analysis by World Weather Attribution At, a group of scientists who analyze extreme weather events. However, parts of eastern Canada, including Ontario and Quebec, experience more heat waves and frequent tropical nights, defined as nighttime temperatures of 20°C or higher.
For example, according to Climate Atlas of CanadaThe average number of tropical nights in Toronto was approximately 6.9 per year from 1976 to 2005. With climate change, under a scenario where carbon emissions are significantly reduced, it is expected to rise to 17.6 per year from 2021 to 2050.
If current rates of carbon emissions continue, the average number of tropical nights in Toronto is expected to reach 20.6 per year from 2021 to 2050. From 2051 to 2080, under the two different emissions scenarios, the average number will rise to 26.4 and 42.8, respectively.
In 2018, a The heat wave covered Montreal from June 29 to July 5; Average temperatures are around 34°C during the day. Nighttime temperatures did not fall below 20 degrees Celsius, in total, 66 people died.
“We are seeing an increase in hot events in Canada that is greater than average global warming,” said Nathan Gillett, a research scientist in environment and climate change in Canada. “Canada’s average warming is twice the global average warming. The maximum temperatures are also increasing at a similar rate. And it’s not just the extremes and the hottest, but the minimum temperatures, and the night minimums that are increasing as well.”
widespread in nature
Average temperatures in Canada have already risen by 1.7 degrees Celsius, and the country is warming more than twice as fast as the planet Earth.
Increased heat waves with above-average temperatures during the day and night are affecting sensitive animals and ecosystems, as well as crops.
a A study published in the journal Global Change Biology Last October it was discovered that night temperatures are rising in most parts of the world. In those areas that experienced more warmer during the night than during the day, there was more cloud cover, higher precipitation and more humidity. This can affect nocturnal animals, but also animals that are active during the day and that use cool nighttime temperatures to recover from heat stress.
“[The changes] Increase the limits that nocturnal species can operate. Institute for Environment and Sustainability, said Daniel Cox, lead author of the study and one of the UK researchers at the University of Exeter.
New set of metrics
With climate change, governments are finding that they need a new set of metrics for extreme heat events.
In the year 2013, Australia has added new colors to its heat maps, The temperatures were higher than anything they had experienced in the past.
Recently, on Tuesday, The UK Met Office has issued its first warning of sweltering temperatures as temperatures are expected to soar into the 30s in parts of the country. Daytime temperatures in the 30s may not seem high compared to some parts of Canada, but it all comes down to what people are used to.
This is how all Junes have been stacked since 1880.
This is the northern hemisphere temperature anomaly compared to the 1951-1980 long-term average. pic.twitter.com/97Bn0SnuGn
In another example of how governments are trying to adapt to rising temperatures, a team from the National Institute for Scientific Research (INRS) in Quebec, along with the National Institute General of Quebec (INSPQ) announced on Wednesday that New warning threshold for heat wave in the province It must be submitted. The warm seasons in Quebec start earlier and end later, the researchers said.
As the Earth continues to warm, air conditioning may seem like a possible solution. The problem is that power is required to run it, and that also produces heat. Cities create “heat islands” where heating is amplified by concrete structures, putting more pressure on people living in hotter climates. Some cities like Toronto And the Montreal It is trying to introduce greener building codes and designs to address this.
“[Heat waves aren’t] “Something we think of as a major risk in Canada, but as the climate warms, we will see this more and more,” Gillette of Environment and Climate Change Canada said. Heat waves cause deaths and are dangerous. And yes, it is something… we will see more and more here in Canada.”