Nares Strait 2012: Approaching Ocean Mooring Line in Kennedy Channel

by Andreas Muenchow, Aug.-5, 2012, 14:22 UTC

 From the southern entrance of Kennedy Channel at 80.03N and 67.25W we can see our mooring site about 45 nautical miles ahead, about 80 km. It will take us 8-9 hours to get there as the ship weaves its way through ice that covers about 50-80% of the surface. The farther north we get, the thicker and harder the ice. Air and ocean temperatures are lower, less ice melt has taken place, and we are closer to the source of this multi-year ice. The very clear skies, clean air, flat ocean, and rugged ice provide ideal conditions to fool the eyes and brain of even experienced sailors: mirages are everywhere as the light is reflected and refracted so many times that not all we see is what it is. Even renowned polar explorer Robert Peary saw land in the 1890ies where there was none, called it “Crocker Land” to honor one of his sponsors, and subsequent explorer toiled in vain to find it.

We are ready and eager to start work in earnest after 2 days of sailing. The recovery of the instruments anchored to the bottom of the ocean for the last 3 years has the highest priority. We need the instruments aboard to get to the data that describe ocean currents, temperature, salinity, and ice thickness at least every half hour continuously since August of 2009. Should the ice prevent us to reach every site, we are prepared to service the automated weather stations, like the one at Hans Island. Dr. Jeremy Wilkinson is hosting the data here in real time. Hans Island is a short distance north of our mooring line. Tonight we will start to measure ocean temperatures, salinity, and densities with depth at 5-7 stations running along a section from Ellesmere Island in the west towards Greenland in the east. The term “night” has no meaning, however, as the sun is always brighter than it is in my garden in Delaware because there is no shade and ice and water reflect all light along multiple pathways.

 At 6 am this morning I saw a ship-sized piece of ice from Petermann Glacier in the distance. It had the undulating surface that is typical of Petermann as well as dirt from rock. Nevertheless, do not know where the Manhattan-sized Petermann Ice Island PII-2012 is right now or if it has left the fjord. Internet access is severely limited for scientists and crew alike. So you, my dear readers, probably know more than anyone aboard this ship where PII-2012 is from browsing NASA’s MODIS archives, if the area is cloud-free.

 The helicopter left the ship half an hour ago with the ice observer and two scientists aboard (Allison Einolf and Dr. Renske Gelderloos) to reconnoiter local ice conditions up to Hans Island 60 miles ahead. While a prudent mariner in these icy waters will always inspect ice conditions ahead via helicopter to extend the 3-12 mile radar range, the helicopter is also an expensive resource at $1,800 per hour. For example, with the currently clear skies overhead NASA’s MODIS provides 250-m resolution bands that are good for ice navigation in Nares Strait, if they were available. RadarSat is even better, but even RadarSat is received aboard the ship only at downgraded resolution to reduce data transmission rates and costs.

 Addendum: The helicopter returned safely with images and videos of ice conditions in Kennedy Channel. Also, as of 2 minutes ago: “In theory we do know where PII-2012 is as this morning’s RadarSat image include Petermann Fjord,” said Ice Service’s Specialist Erin Clark before heading off for lunch after getting off the helicopter.

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