While some might find the October sun to be a welcome departure from Vancouver’s infamous rainy autumns, the unseasonably warm weather is raising alarms among some climate scientists.
On the morning of October 7, the BC government updated the Lower Mainland to Level 5 drought status, the peak of the province’s five-level scale.
This puts Vancouver in a condition of “exceptional drought,” according to Agriculture Canada.
“It’s the continuation of a trend that’s very easy to see in the long term data,” said UBC forestry professor Dr. Peter Arcese. “That trend has gotten much deeper after about 1950, and in our local area, it’s gotten particularly steep since the 1970s.”
“So what we see is the general warming of summer temperatures and an increasing length and depth of drought.”
Environment and Climate Change Canada reported that early October weather broke over 20 community temperature records across BC. Metro Vancouver’s upcoming weekly forecast is mostly sunny, with high temperatures of 20 degrees Celsius.
“The population keeps on growing, the demand for water keeps on growing and the seasonal climate in our neck of the woods has a really sharp contrast,” said UBC earth and ocean sciences professor Dr. Sean Fleming. “It is extremely wet for much of the year, but we also have this really long drought period that can go from anywhere from July to October.”
According to Fleming, that extended dry period, combined with population growth and increased water demand, creates serious water stresses.
“This has been building for years, if not decades,” Fleming said.
As one mitigation strategy, Metro Vancouver has extended lawn watering regulations until October 31. Under the Drinking Water Conservation Plan, residents and businesses are only allowed to water their lawns once a week until this period elapses.
While a press release from Metro Vancouver said reservoir levels are currently normal for this time of year, the province could be required to take more direct actions if the dry spell continues.
“It’s really time to start looking at the experiences and the experiments and the successes of other parts of the world,” said Fleming. He cited Las Vegas’s permanent water policies as one example of effective climate policy.
Las Vegas implemented a number of incentives and policies for reducing water consumption, such as rebates for climate-friendly landscaping.
Arcese, who co-authored a 2020 publication on strategies for increasing conservation financing, thinks that changes in climate policy should be considered thoroughly. Compensatory actions for the current drought such as restricting access to water or removing dams, he said, could lead to unintended social or ecological consequences.
“My personal perspective as a scientist is that we need to find the things that suffer most because of the current conditions, and for which we have some method of improving things,” said Arcese.