'Huge chunks' of ice afloat in northern B.C. lake, as glacier retreats

Helicopter pilot Jamie Tait has seen some impressive sights in his years of flying, but this one was up there with some of the best.

Tait says a large piece of ice recently broke off the toe of the Llewellyn Glacier, at the south end of Atlin Lake, in B.C. He figures the piece was about a kilometre, or a kilometre and a half, long.

"To have these huge chunks of ice floating in the lake — it's pretty impressive," he said, from his home base in Atlin.

That large piece of ice has since broken up into smaller chunks, some of them the size of a city block or a school, he said.

'I was pretty excited'

Tait noticed the changes when he flew over the glacier with some German tourists a few days ago.

"It was probably two days before that when I'd been by, and the toe was still connected. So it's only happened in the last three or four days," he said.

"I was explaining to [the tourists] what had gone on there, and I was pretty excited about it — to see these changes first-hand is pretty fun." 

Tait's been flying in the area for years and has been watching the Llewellyn Glacier as it retreats southward. 

"The story of the glacier is constantly changing, and I like to show clients the old glacier scar on the valley — to show them where the ice was in the early 1900s, and to where it is today," said Tait. "It's a pretty significant difference."

He's not sure, though, why such a huge piece would now break away.

"I just fly the helicopter," he said. "I'm not a glaciologist."

Not unexpected, says glaciologist

Mauri Pelto is a glaciologist.

He's based in Massachusetts, but he's been watching and studying the Llewellyn Glacier for decades.

Pelto hasn't seen any up-to-date satellite imagery of the area, so he can't be certain what Tait's observed.

But he suggests it was a relatively narrow tongue of the glacier that finally broke away — not unexpected, he said.

"The first time I was on the glacier, back in 1980, the lake at the front of the glacier was several different parts, and it was much smaller," Pelto said. "So there's been a really large retreat along that glacier front."

Pelto said it was only a matter of time before that narrow tongue of ice broke off in the water.

"That ice tongue is going to start to float more, and then finally that's what's going to lead to the disintegration — is a combination of thinning, becoming more afloat, and then crevasses that already existed in the ice," he said.

If anything is unusual, it's the time of year, he said.

"Typically, it would happen later in the summer, after you've had a summer of melting."