As another warm week slips by, there are signs all around that we could be on the cusp of a new normal in weather trends.
To the east and north of us, mountain glaciers are rapidly shrinking and substantial ice loss by as much as 70 per cent to 90 per cent will occur by 2100. Those glaciers are the savings banks on which BC Hydro depends to feed reservoirs and on which fish depend for spawning streams.
To the south of us, Californians are furiously trying to come to grips with a worsening four-year drought and they are slashing their water use by 25 per cent.
To the west in the Gulf of Alaska a mass of warmer-than-normal water 1,600 kilometres across and 92 metres deep has been parked for two years and is starting to disrupt ecosystems. Washington State climatologist Nick Bond calls it “the blob” since the warm water sits like a blob on top of colder, denser water.
Recently, a report published in the online journal Nature Geoscience documented the rapid retreat of most of British Columbia’s 17,000 glaciers. Lead author Garry Clark with UBC’s Department of Earth, Ocean, and Atmospheric Sciences wrote that the maximum rate of ice volume loss could occur around 2020 to 2040. That means maximum melting would start peaking just five years from now.
According to Clark, the rate of glacial melt across B.C. is some of the fastest glacial loss on Earth and could be a future contributor to sea level rise.
BC Hydro’s report Impacts of Climate Change on BC Hydro’s Water Resources also records glacial melt. It notes that there has been a substantial reduction in peak winter snow accumulation over the past 50 years right across the province. Winter snow accumulates naturally in huge basins but on average across the province these snow reservoirs have dropped by about 18 per cent.
Snow pack decline is widespread. In California their snow packs are 94 per cent gone. According to Roger Pannett, volunteer weather observer for Environment Canada, snowpack in the local mountains this winter was at a stunning record low of just 15 per cent of normal. And we’re getting drier. Precipitation for 2014 was 11.35 per cent below normal.
“With the Californian high pressure ridge periodically deflecting the jet stream north to the Yukon, precipitation totals (for January 2015) including snowfall were 27 per cent below normal and the third consecutive January with such a drying trend,” he said.
February precipitation was a stunning 36.5 per cent below normal and the 13th consecutive February with lower than normal precipitation. As at March end, total precipitation this year was 21.8 per cent below the 30 year average.
Then there’s the mysterious blob. According to the National Oceanic and Atmospheric Administration (NOAA), not since records began has the North Pacific Ocean been so warm for so long. This region of exceptionally warm water showed up in 2013 and its temperature has persisted by as much as three degrees C higher than average.
Warm water leads to lower volumes of nutrients, less oxygen, and changes in acidity, salinity, and biomass. The net result is that local marine species are getting new neighbours. Ocean sunfish, tropical skipjack tuna and thresher sharks are showing up off Alaska’s coastline. Species intolerant of warm water like salmon will take score and start a northward trek which doesn’t bode well for our west coast fisheries and our food stocks.
It’s time for a serious conversation about our water sources and water-borne food stocks. If glaciers and snow packs are in decline and if oceanic conditions spur anomalies that threaten food sources we need some mitigation plans. Pretty quickly.