The extreme heat many Canadians have experienced this summer could be a glimpse into the future, according to a climate expert.

Environment Canada’s David Phillips warns that the extreme temperatures seen around the world in recent months will be the norm for this time of year in decades to come and that this summer’s weather is a “dress rehearsal” of what is to come.

“This kind of global heatwave and extreme temperatures that we’re seeing this summer is really going to be summer in the future,” he told CTV News. “We won’t be talking about it in 30 to 40 years because that will be the normal kind of condition.”

Phillips added that the effects of extreme temperatures are beginning to be felt around the globe.

“The planet is on fire, it’s overheated and we’re seeing the impacts of that in terms of people dying from the heatwaves, crops are burning up and we’re seeing wildfires. All that is related to the fact that we’re under global fever,” he explained.

More than 100 heat warnings have been issued across large parts of Canada so far this weekend, as parts of eight provinces deal with sweltering temperatures.

Overseas, Lisbon broke a 37-year-old record to notch the city’s hottest temperature ever. Portugal's weather service said the capital reached 44 C (111.2 F) on Saturday afternoon, surpassing the city's previous record of 43 C (109.4 F) which was set in 1981.

Phillips said the planet is going through a “global heatwave”.

“We’re seeing it in four continents, in unlikely places, like Japan and the Koreas,” he said. “In Africa they’ve had the warmest temperatures they’ve ever had. As we speak, parts of Portugal and Spain have heat warnings out. And also north of the Arctic circle too. Everybody is sharing in this fact that this summer is very, very warm.”

Phillips said he is worried by the record-setting temperatures recorded in Death Valley, Calif., last month.

“In July they set records for the hottest month ever on this planet,” he said. “No place has ever been hotter in July than Death Valley. They had four days where temperatures got to almost 53 C.”