Hot summers will be new normal, says study

Record-breaking hot summerswill be the new normal within 20 years due to human-influenced climate change, according to a new study co-authored by the president of the Pacific Climate Impacts Consortium at the University of Victoria.

ClimatologistFrancis Zwiersfoundthat sweltering summershave become at least 70 times more likely over the past four decades. The research shows thatby 2050, virtually every summer will be hotter than any experienced to date.

• B.C. heat wave causes record-breaking power consumption
• Weekend heat wave breaks 10 temperature records in B.C.

Zwiers'study examined wet bulb globe temperature,which is a standard measure of heat that takes temperature and humidity into account.It is often used to determinethe safe exposure levels for people working outdoors in direct sunlight.

Evidence is evident

"The evidence is very clear that we humans are raising the temperature of the planet by emitting more greenhouse gas into the atmosphere," saidZwiers.

People working outdoors in summer will likely be exposed to rapidly rising risks of heat stress in regions with the most significant rise in wet bulb globe temperature, saidZwiers.

Zwiersand his colleagues looked at wet bulb globe temperature changes in 10 global regions.Hotter summers caused by human-influenced climate change were evident in all of them, but the findings showthe Mediterranean region and Asia are feeling the heat the most.

Permanent problem

According to Zwiers, the high temperatures aren't likely to come down in the near future.

"There is strong evidence to suggest that the warming that we have caused is not going to be rapidly reversible.It's essentially permanent on an intergenerational timescale," said Zwiers.

Zwiers warned warmer temperatures will increasethe likelihood of extreme weather situations, such as flooding and fires.

He said the frequency with which we are going to have to takeprotective action is going to increase very rapidly as time advances.

"We need to think strongly about adaptation," said Zwiers, "How we heat and cool our houses. How we move around. And how we issue warnings and get people out of harm's way."

Zwierssaid in the Pacific Northwest, coastal flood protection measures should be a priority.

• Sea level has climbed 8 centimetres since 1992
• National climate change report warns of risk of storm surges on B.C.'s coast
• Climate change to bring great white sharks to B.C. says UBC prof

With files from All Points West.