By Cam Fortems
Kamloops This Week
A preliminary analysis of regional glaciers done for a Shuswap conservation group found they receded by 15 to 35 per cent in the past three decades.
The project was conducted by Forsite Consultants Ltd. on behalf of Shuswap Environmental Action Society. Using satellite photography, it looked at three glaciers in the Adams Lake and North Shuswap region.
“We did a preliminary study and just wanted to get some idea how fast glaciers are melting,” said society founder Jim Cooperman.
The glaciers studied are located east and north of Tumtum Lake and north of Shuswap Lake’s Seymour Arm.
The project analyzed images from 1985 and compared them with images in 2015. Both sets studied were in late August or early September in order to eliminate variation from snow cover.
The two glaciers east and north of Tumtum Lake receded by about 16 per cent while the glacier north of Seymour Arm lost 36 per cent of its surface area.
The numbers are similar to larger estimates done for the provincial B.C. Ministry of Environment, which found ice coverage as a whole across the province decreased by more than 2,500 square kilometres over the period.
The ministry study determined changes in temperature are the root cause of the shrinkage. While snowfall can vary from year to year, a warm summer can melt gains from more than one previous year. It also noted the International Panel on Climate Change believes warmer temperatures are related to climate change.
Cooperman cautioned the regional study looked only at surface area. There are other, more intensive methods including looking at ice depth.
The society wants to build on the project by gathering more estimates and looking at long-term outcomes of the shrinkage. The biggest concern is disappearing glaciers will cause a corresponding loss of freshwater for streams and rivers in late summer and early fall.
That could translate into drinking water shortages and loss of water for the famed Adams River sockeye run.
Another proposed step for the project involves bringing in a hydrologist who can map out what the shrinkage may mean to stream and river volumes over the next decades.
“The goal is to gather as much information as possible and present a report to cities and local governments and get them interested,” he said.