Shift in the Wind May Push Gargantuan Fort McMurray Fire Toward Tar Sands Facilities on Saturday

6 May, 2016

The Fort McMurray Fire is now so vast that it has both burned through and completely surrounded the city, its airport, and the neighboring community of Anzac 31 miles to the south. Spinning out blazes in a long tail across the green forested land of Canada, the fire now appears to cover about 40 miles of distance and 10 miles of width at its longest and widest points. A secondary fire to the northeast of the main blaze also appears to have lit off.

(Fort McMurray Fire as seen from above in the May 6 NASA/LANCE MODIS satellite shot. This huge fire now covers an approximate 10×40 mile swath of land, is throwing off numerous pyrocumulous clouds, and has spawned a secondary large fire to the northeast. In the upper left hand corner of the image above we see the bald landscapes of tar sands facilities. Smoke plume analysis indicates that the northern extent of this monstrous fire is just 3 miles to the south of the nearest tar sands facility. For purposes of scale, bottom edge of frame is 60 miles. Image source: LANCE-MODIS.)

Viewing the massive scope and extent of the blaze, one can see why an evacuation convoy of 1,500 vehicles — composed of members of the fire response team and a number of stranded evacuees — was unable to flee the city today. BBC News reports indicated that the convoy encountered walls of flames 200 feet high and was forced to turn back to a city that finds itself surrounded with walls of flame on every side. This is the second time in two days that an evacuation convoy attempted to leave the fire zone and the second time that all ways out were found to be blocked by the fires. Hundreds of people remain stranded in the fire zone and officials say it will take four days to move them once a clear pathway out is found.

Hot Winds to Drive Fire Toward Tar Sands Saturday

GFS model forecasts indicate that temperatures will rise into the mid 80s tomorrow. Yet another day of record hot readings for a climate change baked Canada. Winds are predicted to shift toward the south. And very dry conditions will continue to worsen the already extreme levels of fire danger. With the fire now burning just 3 miles south of the Athabasca oil production facility — a section of the tar sands that was evacuated yesterday due to fire encroachment — it appears that these winds will likely drive the fire toward and, possibly, into that industrial section.

Over the past few days, this fire has shown an ability to move very rapidly — covering many of miles of ground in just a short period. Trees surrounding the barren strip mines of the tar sands facilities provide abundant fuel for these fires and volatile chemicals produced in the facilities add an additional hazard. The tar sands soil is laced with bitumen — which is not typically concentrated enough to burn. However, the extreme heat of these fires may cause some of the more concentrated zones to smolder — adding to potential fuels and fire hotspots.

(Southwest winds and temperatures in the 80s will worsen fire conditions on Saturday — creating a risk that the Fort McMurray fire will sweep into the tar sands production facilities. By Sunday, another front brings with it the potential for rain — which may help firefighters contain the blaze. Image source: Earth Nullschool.)

Given the predicted weather conditions, the available fuels, and the extraordinary scope and force of the ongoing conflagration around Fort McMurray there is risk that fires will invade the tar sands production zone on Saturday. To this point, it’s worth noting that Arctic and Northern Latitude wildfires like the Fort McMurray Fire have had a tendency to burn for a long time during recent years — lasting for many days and sometimes weeks. Adding to the tree fuels, the ground provides its own set of ignitable materials in fires so large and so hot as this one. The top layer of soil contains old leaf litter, organic material and deadfall — a layer about three feet thick that will burn in the most extreme blazes. This region of Alberta also contains deposits of discontinuous permafrost. And during recent years, these permafrost zones have thawed more and more with the advance of global warming. Permafrost is carbon rich and produces its own peat-like fuel which can burn and smolder over very long periods.

Record heat and climate change, therefore, provide an explosive combination of new fuels and added ignition sources for fires like the one that is now engulfing so much of this tar sands production zone. And as bad as these fires have been over the past week, tomorrow may see the situation again worsen.

After the heat and dangerous wind shift on Saturday, Sunday brings with it a 40 percent chance of rain. And given such a large and hot burning fire — rain is really the best hope that firefighters have of getting this enormous blaze under control anytime soon.

Links:

LANCE-MODIS

Canadian Wildfire Halts Evacuation Convoy

Fort McMurray Fire Updates

Earth Nullschool