As Mother Nature releases her icy grip on the mountain passes and secret high altitude roadways of southern Afghanistan, NATO and Afghan troops are gearing up for a long-expected Taliban spring offensive.

Each year since 2002, when the U.S.-led coalition first invaded, Taliban militants have stepped up their attacks as the spring thaw began. And this winter the militants fighters have been promising such a campaign would again arrive with the warmer weather.

But what exactly does that mean in the context of a shadowy army that wears no uniform, and has few known bases of operations? Whose soldiers can be peasant farmers one day, and armed Islamist militants the next?

Most likely, says Geoff Hayes, it will mean more of what Canadian troops have experienced in the past few days: Small, hit-and-run style attacks that are difficult to defend against and -- as proven this week -- often prove deadly.

Since Sunday two such attacks have claimed the lives of eight Canadian troops.

"It becomes like the campaign season when the weather finally is warm enough and the ground is hard enough that the Taliban are massing forces," Hayes told CTV.ca.

A history professor at the University of Waterloo and associate director of the Laurier Centre for Military, Strategic and Disarmament Studies at Wilfrid Laurier University, Hayes has edited a new book titled "Afghanistan: Transition Under Threat."

He said last year proved deadly for the Taliban whenever they clashed force-to-force with British, American and Canadian troops -- arguably with the militants losing every time.

As a result, he suggested the militants will step up their use of terror tactics such as suicide bombings and IEDs. But he wouldn't rule out the possibility that the Taliban would attempt a major spring push to try and reclaim Kandahar, once a Taliban bastion.

"They're trying to ensure they not only continue to disrupt southern Afghanistan, but if they can regain the stronghold they once held in Kandahar it would mark a serious blow to the redevelopment of the Afghan government," Hayes said.

Anthony H. Cordeman, a military analyst with the U.S. Center for Strategic and International Studies in Washington, recently predicted a decrease in the number of large-scale Taliban attacks like those that were waged last spring.

He told The New York Times that's because the militants have suffered major losses in battles over the past year, and quite simply their numbers are down.

But, he warned, "This is an experienced and adaptable adversary," and there is likely to be an increase in suicide attacks and roadside explosives to make up for the decline in major pitched battles.

He said that the Taliban's full spring campaign hasn't yet begun in earnest.

Meanwhile, the expected offensive is the main topic of discussion at a Quebec City gathering of military brass from Canada, the U.K., Australia, the Netherlands, Denmark and Romania that was underway Thursday.

U.S. Defense Secretary Robert Gates, who is attending the meetings, has said NATO should turn the tables this year and bring the offensive to the militants.

That's already underway, in part, since last month when Operation Achilles, a major NATO and Afghan campaign designed to take the battle to hardcore insurgents in southern Afghanistan, the Taliban's spiritual heartland, kicked-off in Helmand province.

"We're going into Helmand, and Helmand is one of the most unstable provinces in Afghanistan. It has the biggest drug problem, and this is part of a wider multi-national force to try and deal with this kind of thing. So it is pre-emptive," Hayes said.

More than 5,000 troops are involved in the operation.