USCGC Healy Cruise HLY-1502
US Arctic Geotraces Weekly CTD/Hydrographic Team Report 03 from Jim Swift, UCSD/SIO, CTD/hydro team scientific leader at sea

Sunday, 30 August 2015, 2:45 pm, local date and time (2245 30 August UTC)

86.3°N, 170.6°E (in the Makarov Basin of the Arctic Ocean)

air -5.0 degC / 23 degF

water -1.4 degC / 29 degF

wind 16 knots from E

En route to station 29 in near 100% ice cover (at the time of this report)

Note: This is a hydrography-oriented report from Jim Swift, who is working with the SIO Oceanographic Data Facility (ODF) CTD/hydrographic team on the US Geotraces Arctic Ocean expedition led by Dr. David Kadko, FIU, chief scientist. This is not a report from Dr. Kadko or the other science teams.

Dear Colleagues,

We are making excellent progress north, keeping to the planned replication of the stations occupied on the 1994 trans-Arctic section, thus providing a look at 21 years of change in the temperature, salinity, oxygen, nutrients, CFCs, and dissolved carbon in Arctic Ocean waters from surface to bottom. (The Geotraces trace element and isotope [“TEI”] program is going well, too.) A preview of coming attractions in hydrographic data results: Compared to 1994 there is marked impact of freshening on the waters above the Atlantic layer, but underneath that mid-depth temperature maximum the waters are more saline.

The ice conditions in the area we are traversing border on astonishing to a person like me who recalls the thick, tough, old ice of the Arctic Ocean in

  1. If my memory serves, in 1994 CCGS Louis S. St-Laurent and USCGC Polar Sea were continually looking for a workable course around thick ice floes - the size of football fields to small towns - occasionally necessitating a slow crunch through a tough area we couldn’t go around. Helicopters were used to scout out feasible routes. As we know from recent published scientific studies, the older, thicker ice has in more recent years occupied a smaller area of the Arctic Ocean, nearer Greenland and the Canadian Archipelago. Thus much of the ice we are traversing is first year ice, but there is multi-year ice out here, along with thick ridges. The ship is able to follow leads around the ridges and multi-year ice, and motors well through the extensive first- year ice. (I enjoy the “Richter 3-4” jostling as the ship gets buffeted by the ice.)

It has been chilly all week - in the lower 20s in Fahrenheit degrees - with occasional light snow and periods of 15+ knot winds. Sometimes we see bear tracks in the snow, though I am not aware of sightings in the past few days. There is new ice on the small leads, with some frazil and grease ice on large ones. We are prepared for the weather and all CTD/hydrographic operations are going well, with continued excellent data quality.

Last week I enjoyed providing lectures to the ship’s oceanography class, as other faculty on board have been doing. I ended up with a session on water masses and the Meridional Overturning Circulation, favorite subject areas of mine.

We are now well north of the maximum polar latitude from which a ground station can “see” a communications satellite in geosynchronous orbit - which in practical terms means the end of internet for several weeks. The Coast Guard does provide email via Iridium satellites at a very much slower communication rate. For now we are restricted to text-only, generally with no photos or larger attachments coming or going. (If you receive this with a photo, thank the Coast Guard for allowing it.)

We have a Geotraces “super station” coming up tomorrow. This series of casts and ice work will involve a planned 52 hours on station (compared to no more than 4 hours for one full-depth hydrographic cast). The ship was designed to store wastes for long periods - even engine cooling water is held I think - so as to minimize disturbance of the water we are sampling with our science gear. But 52 hours is exceptional. We are preparing for two minute showers, use of paper plates and cups, no laundry, etc.

The Coast Guard has really pulled out the stops on support - we have enthusiastic, capable crews leading every science operation, 24 hours a day. The meals continue to be very good - my favorite last week was excellent New England clam chowder, honey-Sirracha glazed salmon, wild rice mix, sautéed summer squash, fresh-made dinner rolls, and strawberry shortcake!

The topper: We are only 220 nautical miles from the North Pole.

All is well.

This is PolarTREC teacher Bill Schmoker’s photo of Greg Cutter’s (Old Dominion University) trace metal rosette being recovered after a long cast in the ice.

Jim Swift

Research Oceanographer

UCSD Scripps Institution of Oceanography

PS - Feel free to send questions to me at james.swift@healy.polarscience.net.