A colleague who lives on unceded Syilx territory in the north Okanagan told me recently that her friends at a fish hatchery in the area are deeply concerned about the size of the salmon return this year.
“The heat last year created a ‘thermal block’ in the watershed that the fish are sensitive to, and they didn’t return to spawn in their regular channels,” she says. “The expectation is that the return will be 40 to 50 per cent less than normal.”
Many of us may have been regretting this spring’s persistently cool temperatures in B.C., but we may also have had reason to console ourselves. “It’s better than another heat dome,” we might acknowledge. “The rain and cool is keeping the fires down,” we may say to one another. “Fog and drizzle is much better than smoke,” we might even say.
The unseasonably cool and rainy spring and an early summer forecast tending to cooler-than-normal temperatures feels like a reprieve, but after last year, a sense of unease lurks beneath. We know we’re not out of the woods.
Environment Canada has provided a tentative forecast for the summer. A cooler pattern might continue over the Island into July, thanks to this year’s La Niña-derived cooler sea surface temperatures. After that, days of “normal” hot weather may follow through the rest of the summer, with temperatures in the low-30 degrees Celsius, well below the record-breaking 40-something degrees recorded last June.
However, long-term seasonal weather predictions tend to have a lot in common with the stories peddled in the fiction departments of local bookstores or on the social-media channels of proponents of conspiracy theories. Furthermore, last year’s crushing heat dome came in the last days of June, after a cool, rainy spring much like the one we’ve tolerated this year.
Earlier this month, Environment Canada meteorologist Derek Lee was reported in these pages as saying, “The heat dome was definitely one of those historic events. It was a one-in-a-100-years event, so I surely hope that won’t occur again this year.”
(For the unofficial record, the old-fashioned $5 mercury thermometer outside our kitchen window read 51° C last June 29. Nature Boy has since augmented our household temperature-reading capacity with a far more accurate Internet-connected weather station. If temperatures in our yard should ever attain similarly lofty heights, he wants certainty to the first decimal point.)
Last summer’s heat was punishing. Adding to the current sense of unease is an awareness that consequences of the extreme heat will haunt us for years.
Residents of Lytton and other wildfire-evacuated areas bore the immediate brunt of the heat. But communities far to the east also suffered, as they choked on smoke for month after month.
The communities along the Nicola, Thompson and Fraser rivers and tributaries that experienced catastrophic flooding either directly or indirectly last fall also felt the consequences of last summer’s heat events. The flooding that swept through towns, cities and farms and swept away highways, bridges and buildings was exacerbated by the damage the wildfires did to upstream-watershed forests and slopes — wildfires made possible by the heat.
Those slopes will remain unstable for years, until either the sediments slide down the hillsides or root networks of new generations of shrubs and trees grow strong and widespread enough across the slopes to strengthen and hold the soils.
And, as my colleague from the Interior reports, the floods also destroyed salmon redds and fish-spawning beds throughout many of southern B.C.’s creeks and rivers.
Last year’s warmer-than-usual stream temperatures hindered normal reproduction in many of southern B.C.’s salmon, sturgeon, steelhead and trout. Those that survived being par-boiled and those whose passage to spawning grounds wasn’t blocked by thermal plugs— as well as any eggs the spawning fish managed to lay — would have been washed out or buried under loads of sediment.
The effects of those lost fish generations will last for years.
Summer used to be the easy season of the year. For four to six months, we could relax and chill in the warmth before battening down the hatches for more wind, rain and cold.
Now, the season of ease carries its own underlying threats and inescapable, lasting dangers.