Explained: The reason behind extreme temperature in US and Canada

Extreme temperatures due to heat waves have taken more than 100 lives in both Canada and USA

Even after many cooling centres were opened in various regions, the death toll is ‘rising by the hour’

More than 400 people have died in the western Canadian province of British Columbia (BC) due to the record-breaking heat waves experienced in Canada and north-western USA. The BC region witnessed an increase in sudden death rate by 195 per cent within the last five days, chief coroner Lisa Lapointe said in a statement on Wednesday.

More than a hundred people have died in this heat dome in various regions of Canada and USA as well. These provinces are facing all-time high temperatures due to a phenomenon called ‘heat dome’.

What Is Heat Dome

According to the National Oceanic and Atmospheric Administration (NOAA) of the US Department of Commerce, a heat dome happens when strong, high-pressure atmospheric conditions combine with influences from La Niña (a climate pattern in the Pacific), creating vast areas of sweltering heat that gets trapped under the high-pressure ‘dome.’ Basically, heat dome is a mass of warm air stuck over a particular area.


According to NOAA, heat domes take place when there is a strong change (or gradient) in ocean temperatures from west to east in the tropical Pacific Ocean, which causes more warm air, heated by the ocean’s surface, to rise over the Pacific, and decreases the process of heat transfer.

Also read: Heat wave grips US West amid fear of a new, hotter normal

Effects, Duration and Frequency of Heat Domes

The heat dome causes the temperature in the regions to become extremely hot, due to which the people who do not have air-conditioned houses find the temperatures unbearable. This phenomenon also results in destruction of crops and other vegetations in the area, sometimes even leading to droughts. Heat domes also act as one of the main reasons behind wildfires. Last year, millions of houses in California faced blackouts, albeit for a brief period of time, after a large number of people switched on their air conditioners at the same time due to heat dome.

The governor of Oregon has issued a state of emergency due to the scare of wildfires in the region.

Experts say that heat domes typically last for a week. These are becoming more frequent in recent times, with climate change being one of the major reasons behind the formation of a heat dome.

Climate change increases the intensity of heat waves. Zeke Hausfather, a climate expert at the Breakthrough Institute, told NDTV that climate change acts like a ‘steroid’ to all weather conditions; heat waves would have been still there in the absence of climate change, but it would not have gone up to such extreme temperatures.

Also read: Climate change causing more, intense cyclones in Arabian Sea

Even after many cooling centres were opened in various regions, according to the police, the death toll due to heat dome is ‘rising by the hour’. Canadian Prime Minister Justin Trudeau offered condolences to the victims of this heat dome and also warned that this will not be the last such incident.