An “out and back” survey over the Beaufort Sea

 

 

Day 4 First Arctic Ocean survey day. Today we flew out over the Arctic ocean from Inuvik. As we know, the Arctic is where some of the most significant planetary heating has been measured. The impacts range from thawing permafrost on land, shortening of the winter snow season, to changing sea ice dynamics. In terms of this last point, particularly, the extent of sea ice that survives from one year to the next, or multi-year ice, has shrunk profoundly in the last 30 years. As a result, the winter sea ice is dominated by first year ice which can melt out earlier each year as the planet warms.

AWI has been running these yearly campaigns to monitor key places in the Arctic Ocean and Canadian Arctic Archipelago (CAA) to keep track of changes. The primary measuring instrument is the Icebird, an EM induction system that measures sea ice thickness beneath the aircraft. A good introduction can be found here. With a laser scanner and a snow radar, the combined system can estimate ice and snow thickness as the aircraft tracks along. The Icebird measurement technique requires the pilot to fly at very steadily at approximately 200 feet above the sea ice with the Icebird lowered to within 50 feet of the ice – that is wild! The goal today was to fly a survey line from 71N – 74N with the Icebird deployed and the lidar and snowradar operating, and return at 1000 m asl and collect CryoSAR observations of the ice.

 

Map of the sea ice survey over the Beaufort Sea on April 12

After checks were complete we set out from Inuvik over TVC and on to the coast. As we approached the coastline, we are required to wear our survival suits. These keep us secured and hopefully warm should we end up ditching in the water. This not something to dwell on, but is why we have all completed underwater egress training (Jeff and I were trained in BC by ProAviation – see here for what is entailed).

 

Checking systems are nominal

 

Time for a quick snap 

Then out over the sea ice. The “Bird” is deployed by lowering it on a long cable from its stowed position beneath the aircraft. This is done at around 400 feet above sea level (asl). Once ready, the Polar 5 descends to its nominal 200 ft asl altitude and the bird whizzes along behind at about 50 feet asl. This means that as you sit in the cabin, you are suddenly aware of all the detail in the snow and ice and the leads in the ice (gaps between ice floes) and places where there are pressure ridges in the ice (sea ice drifts around everywhere- compression ridges are where one ice floe pushes against another and leads form where extension in the ice breaks it apart.  The sea ice in this region is dynamic and is part of the Beaufort gyre which typically rotates clockwise. The ice is constantly on the move even though it seems static when you look at it. So there is lots to see.

 

Polynya near the coastline

 

Ice ridge

 

 

Open water in the ice

 

Pseudo-melt ponds (Christian says they are not melt ponds) in the sea ice

During the deployment of The Bird, the cabin crew must keep as still as possible since interior motion can affect the flight stability: Arttu who was supervising the snow radar had to stand for 2½ hours. Although he is  6’ 7” his head still does not touch the cabin ceiling which is good! 

 

 

Tall person standing still in the cabin during the Icebird deployment

Thanks to some fine planning by Arttu and Christian, we were able to survey a stretch of MYI. This can almost be seen in the video below towards the end that has some older first year ice to start with that transitions into MYI.

 

Flying the Polar 5 for these kinds of surveys is very challenging. However, Alan the pilot and Shannon the first officer were able to provide some excellent stability in the flight. After ~550 km we turned around. The return journey was quicker but included some CryoSAR acquisitions at higher altitude.

Back on the ground after the 5 hour flight we were happy that a successful data acquisition was completed. Christian was especially happy that we captured data over multi-year ice, 

Five hours on an aircraft is a long time, as we all know.  So we were happy to be back on the ground. In case you are wondering, all crew bring a bottle on board for these flights since there are no toilet facilities. So it was great to be back on terra firma. One thing though, after a couple of hours, I found my brain thinking my body was still gently undulating as if it was still on the aircraft. Note to self – don’t look up symptom on the 'interweb' - apparently WebMD calls this effect Mal de Debarquement Syndrome – everyday’s a school day!

Dinner was at the McKenzie Hotel where their restaurant, Mamuqtug, served a mean muskox Bolognese with pappardelle pasta :) And then bed by which time the symptoms had subsided.

Tomorrow: a rest day as there is a flight crew changeover and the weather is not a good fly day forecast.