As the territory looks to adapt to climate change, it must map out one of its most critical resources SA国际影视传媒� ice, industry experts say.

Ice is a main ingredient in permafrost, which underlies about 50 per cent of Canada, but in the NWT it affects SA国际影视传媒渏ust about every community,SA国际影视传媒� said Kumari Karunaratne, acting director of the NWT Geological Survey.

Ice is also a critical component of winter roads and warmer winters are shortening their existence in the NWT, presenting challenges for maintenance and transportation reliability, said Kevin McLeod, assistant deputy minister of asset management for the territory's Department of Infrastructure.

SA国际影视传媒�For ice roads and ice bridges, clearly we need mother nature to give us cold consistent temperatures to make (them) as safe as possible,SA国际影视传媒� said McLeod. SA国际影视传媒�ItSA国际影视传媒檚 getting colder later and warming up sooner. As a government and provider of that infrastructure, we need to decide what we should be doing about that.SA国际影视传媒� Options include shifting from reliance on ice roads to all-weather roads, he said.

In the 1970s and 1980s, ice roads lasted between 76 and 80 days. By the early 1990s and 2000s, the ice road season shortened to about 60 days, said McLeod.

In the Climate Change Strategic Framework, the territory has an adaptation strategy to tackle climate changeSA国际影视传媒檚 effects on infrastructure, said McLeod, an element of which was the construction of the all-weather Inuvik-Tukotoyaktuk Highway.

SA国际影视传媒�At the end of the day you need to give the travelling public a reliable transportation network,SA国际影视传媒� he said.

Connecting Whati by an all-weather road will connect a community whose winter road season is shrinking, said McLeod.

SA国际影视传媒�In order to provide consistent and resilient networks, we're moving that ice road to an all-season road. Those are the kind of long range strategies that the government is seeing as viable,SA国际影视传媒� he said.

In March, the Mackenzie Valley Review Board issued its approval of the all-weather road to Whati, along with 23 recommendations to manage impacts to the wellbeing of Whati residents and to protect caribou.

In the approval of the all-weather road, the board stated that the project would be built over a permafrost area and require the developer to create a permafrost management plan.

SA国际影视传媒�The project is partly proposed to respond to the effects of climate change on the Whati winter road,SA国际影视传媒� the report states.

Unfortunately, climate change could also affect the all-weather road through thawing permafrost and increased maintenance costs and safety risks to users, the report states.

A socio-economic report on What矛 published by the 罢艂谋台肠丑辞台 Government states its concerns about an all-weather road, which include reduced safety, increased pressures from hunting and fishing and increased industrial development.

The report lists access to cheaper goods, cheaper and more reliable transportation solutions, jobs and economic development and increased mobility to other communities as benefits.

As new roads are built, the GNWT is working with experts to understand how permafrost will impact road infrastructure in the North, where climate change effects are more visible, said McLeod.

SA国际影视传媒�We are leading the charge in a lot of cases in terms of our research and sponsoring of test sections and think tanks to say, 'This is our real life problem. What are some real life solutions?'SA国际影视传媒� said McLeod.

The territory requires more data to understand the full extent of permafrost structures and which land is at greatest risk of permafrost slumping and thaw, said Karunaratne.

Frozen ground provides stable building conditions, but changing thermal conditions melt the ground and threaten structural integrity, she said.

SA国际影视传媒�Permafrost is not just a few feet,SA国际影视传媒� she said. Above the treeline, it can be hundreds of metres thick.

Its integrity is affected by air temperature, the presence of vegetation, duration of winter season and overall precipitation in winter and summer.SA国际影视传媒�

Permafrost engineers design infrastructure with foundations that suit the thermal makeup of permafrost to keep it stable, she said.

SA国际影视传媒�If we donSA国际影视传媒檛 know how the climate is going to change and how it will affect the permafrost, itSA国际影视传媒檚 very hard to design a road to withstand a climate that we have not seen before,SA国际影视传媒� said Karunaratne.

The road between Yellowknife and Bechoko is one example of SA国际影视传媒渋ce rich permafrostSA国际影视传媒� structures, called lithalsas, which are caused by the expansion of ice beneath the surface of the soil

The frost heaving they cause mean the highway will constantly require maintenance, said Karunaratne.

Planning infrastructure on a precarious landscape requires mapping and characterizing permafrost features in depth, she said.

In the new GNWT climate change strategy, permafrost is mentioned 105 times. However, there is limited mapping, said Karunaratne.

This year, the Canadian Permafrost Association formed to foster communication between permafrost scientists and governments, communities and engineers.

Remote sensing can be used to identify permafrost formations like lithalsas and find out where ground is particularly vulnerable, said Karunaratne.

Studies are now identifying examples of SA国际影视传媒渕ega slumps which are the size of downtown Yellowknife, which are much much bigger than weSA国际影视传媒檙e used to seeing,SA国际影视传媒� she said.

Students studying the northwestern arctic by satellite are mapping active slumps, which line up closely with the last ice sheet that covered North America.

SA国际影视传媒�It shows where there is ground ice and we should be really careful about choosing where we disturb the landscape,SA国际影视传媒� said Karunaratne.