Will global warming lead to agriculture in the Arctic?
The agricultural regions of Canada:

are located on suitable soil types:

Much of the unfarmed area is the Canadian Shield (shades of red below):

The current surface expression of the Shield is one of very thin soil
lying on top of the bedrock, with many bare outcrops. This arrangement
was caused by severe glaciation during the ice age, which covered the
Shield and scraped the rock clean. The lowlands of the Canadian Shield
have a very dense soil that is not suitable for forestation; it also
contains many marshes and bogs (muskegs). The rest of the region has
coarse soil that does not retain moisture well and is frozen with
permafrost throughout the year.

I think the &quot;coarse soil&quot; is Glacial Till.

This is melting permafrost. I don't think it will be suitable for agriculture.

CLIMATE CHANGE ADAPTATION AND CANADA’S CROPS AND FOOD SUPPLY (2013) (122 pages) discusses warming, precipitation, soils and other factors.

There is definitely potential for a northern expansion of agriculture
as a result of changes in heat and moisture in [the western prairies],
although most of these lands will remain only marginally suitable for
farming because of poor soil conditions.

Edit:
An eroding coastline exposes permafrost along the Mackenzie Delta. Photo: Roger McLeod / Natural Resources Canada
High resolution version from Arctic tundra is 80 per cent permafrost. What happens when it thaws? - The Narwhal:
https://thenarwhal.ca/wp-content/uploads/2019/03/Coastal-Erosion-Permafrost-Roger-McLeod-NRCan--e1551913545654-1920x1080.jpeg
Edit, Oct., 2020:
Canada could be a huge climate change winner when it comes to farmland


In this map from the study, areas that transition from no current suitability for major commodity crops to suitability for one or more crops are depicted in blue, while currently uncultivated areas that transition to suitability for multiple major commodity crops are shown in red. (Hannah et al, 2020)


KC acknowledged the study looked only at climate as a factor when determining where crops could be grown in the future, and didn't take into account things like soil quality.


Soil scientist David Burton of Dalhousie University, who wasn't involved in the study, says that could have a big impact on how much of the potential new farmland is actually arable.
&quot;The soils of Southern Canada have taken 10,000 years to develop,&quot; he said. &quot;Rapid change wouldn't necessarily make soils in Northern Canada suitable for production.&quot;


Johanna Wandel, an associate professor of geography at the University of Waterloo who edited a book called Farming in a Changing Climate, agrees the soil in much of Canada would likely be unsuitable for growing crops, as it's too rocky or acidic.