Nearly a year ago, flood waters Large swathes of southwestern British Columbia. Mudslides destroyed parts of highways and swollen and turbid rivers washed away homes and bridges.
Now, the region has the opposite problem: Months of drought are beginning to affect what was once called the “wet coast” of Canada.
As unpredictable weather events become a hallmark of climate change, experts warn that the two events are linked — and that a culture of overconsumption and resource mismanagement threatens to further amplify the effects of the current crisis.
The impact of the prolonged drought is underlined by recent footage showing some 65,000 dead salmon clogging a dry stream. More than 200 forest fires have caught on fire, and temperatures have fallen in recent weeks. The province’s energy regulator has already warned that the drought will have an impact on hydropower operations.
Eight communities have entered a level 5 drought, with regional authorities warning that “negative impacts on social, economic or environmental values” are almost certain. On Monday, the Sunshine Coast, a community less than 100 kilometers north of Vancouver, declared a state of emergency as water supplies dwindled to dangerously low levels.
Other regions experienced similar dismal conditions. In a typical four-month period between July and October, Victoria, the capital of British Columbia, typically sees close to 100mm of rain. But since July, only 2 mm have fallen to dry land. In the Fraser Valley, it dropped just 10mm – well below the average of 220mm.
But experts warn that the severity of the drought is not just limited to a lack of rainfall. Instead, they say, residents need to understand comprehensive and complex hydrological systems — and the impact of human actions in amplifying the current crisis.
“Factors that cause a particular drought occur randomly over time. We simply cannot blame the current wave on the lack of rain over the past several months,” said Yunus Alila, a forest hydrologist and professor at the University of British Columbia. Big mistake.”
Alila said the largest source of water to replenish streams, streams and lakes in the region is not rainfall but ice buildup in the mountains.
Snow accumulates gradually during the season and, as it eventually melts, provides a consistent resupply of water to aquifers and reservoirs.
When you turn back Atmospheric rivers Long, narrow bands of atmospheric water vapor stretching from the tropics to higher latitudes passed over southwestern British Columbia in November, dropping an uncharacteristically large amount of rain at high altitudes, wiping out bits of the snow mass.
“Ten months ago, when we lost 30 to 40 centimeters of snow in 48 hours, it likely exacerbated the effects of the drought we’re seeing now,” he said. As a result, the critical groundwater recharge was much less than required.
Experts warn that the duration and intensity of rivers in the atmosphere It can be linked to climate change It is expected to increase in the coming years.
Allila also pointed out a number of other factors, often the result of human action, that likely exacerbated the effects of the current drought.
Clear large-scale cutting of provincial forests He is among the worst offenders, having dramatically altered the county’s landscape.
Newer forests, planted to replace what has been cut down, take up much more groundwater than areas of old growth. On the coast where the drought is worse, the problem is compounded: small coniferous trees consume water much more vigorously than their counterparts adapting to the scarcity in the interior of the province. With less water available, transpiration is reduced, which means trees release less moisture back into the air.
Even the creation of logging roads has a profound effect on groundwater recharge, diverting precipitation away from the soil and into ditches that help drain the roads. These trenches are connected to a network of sewers under the roads which in turn are lined with existing canals and grooves.
The water is eventually pushed into the ocean, rather than being sucked up by the land. This feeding is especially useful in the late summer and early fall months, when precipitation is at its lowest.
“We have reached a point of no return in this county, due to the massive amount of obvious logging they have done over the past 20 years. The damage has already been done,” he said. exacerbating the effects of climate change.
Experts also warn that the culture of excessive consumption, supported by the belief of many residents that the country’s water resources are limitless, is a danger to the future.
Zafar Adil, a professor in Simon Fraser University’s School of Sustainable Energy Engineering, says Canadians often have a “misguided” sense that fresh water is a limitless resource in the country.
“People tend to not understand the consequences of excessive water use,” he said, pointing to a number of lawns in his neighborhood. “Especially in [coastal] British Columbia, there is a sense of invincibility that is invincible that we have had enough – we will never lose water.”
Adil also warns that when it eventually rains, the clay-like consistency of dry soil increases the risk of flash floods.
“There’s really not much we can do in the short term when it comes to adaptation… and I don’t really know what the forecast is for the next couple of months in terms of rainfall,” he said. “But if we get another event that looks like atmospheric rivers, God forbid we have this kind of situation. I think it will be much more harmful than last year.”