Canadian Archepelago Throughflow Study
Daily Logs

Henry Larsen 2007 Science Cruise Report : PDF format, approximately 2.2 MB

Click here to see a CBC video with footage from the Henry Larsen from their series The Big Melt.

Science Plan: CCGS Henry Larsen
Canadian High Arctic, August 2007
International Polar Year - Canada

Chief Scientist: Dr Humfrey Melling

Dates of Operation:
9 August to 1 September 2007 (nominal)

Areas of Operation:
1. Nares Strait, from Smith Sound to Hall Basin with focus on a section across Kennedy Channel at 80.5 degrees N.
2. Cardigan Strait, Hell Gate, Fram Sound

Elements of the Scientific Programme

CAT Mooring Project - Nares Strait
  • Recover internally recording instruments on 12 oceanographic moorings
  • Service recovered instruments and mooring components.
  • Re-deploy internally recording instruments on oceanographic moorings at 18 sites (perhaps more).
  • Measure seawater properties via profiling CTD on cross-sections at 5 locations along the strait.

CAT Mooring Project - Cardigan Strait
  • Recover internally recording instruments on 2 oceanographic moorings in deep water.
  • Service recovered instruments and mooring components.
  • Re-deploy internally recording instruments on oceanographic moorings at 2 sites (perhaps 3).
  • Measure seawater properties via profiling CTD on cross-sections in Cardigan Strait, Hell Gate, Fram Sound.

Multi-year Ice Properties - Arctic straits
  • Measure profiles of thickness across selected multi-year ice floes using surface-based electromagnetic induction radar and drill holes, coincident with imaging by Radarsat.
  • Measure ice compressional strength in holes drilled into some of these multi-year ice floes.
  • Deploy satellite tracking beacons one or two floes to facilitate re-measurement at a later time.
  • Observations are to be carried out in Nares Strait, Norwegian Bay and western Jones Sound.

Arctic Transportation Project - Arctic straits
  • Measure the acceleration components of (viz. total force on) CCGS Henry Larsen when breaking ice, using an autonomous measurement and logging system (MOTAN).
  • Record scenes from a forward-looking video camera mounted at the bow. The images will be used to identify the ice features whose impacts are associated with high forces.
  • Photograph ice blocks from floes broken by the ship using a down-looking camera. The images will be used to determine the thickness of ice broken during the ship-ice interaction.

Shoreline Pick-ups
  • Equipment needed for measurement of the thickness and strength of multi-year floes from CCGS Henry Larsen is presently cached at Alexandra Fjord (78 53 N, 075 48W). The total weight is approximately 1228 lb in 19 boxes. This equipment is needed on board as early as practical during the expedition.
  • We have received a number of requests from colleagues to retrieve ocean instruments now stranded within our working area in the Canadian Archipelago. All objects are small and readily carried by helicopter. There are three beached objects: one in St Patrick Bay off Robeson Channel, one in Muskox Fjord off Jones Sound and one on the south-western Ellesmere coast in Norwegian Bay. We have made no firm commitments to address these salvage requests. They will be addressed opportunistically.
  • There are also two satellite tracked beacons still adrift which mark floes to which return visits would be advantageous to the ice-properties activity on this cruise. Both are presently (July 25) on fast ice, one in northeastern Baffin Bay and one in western Jones Sound. Possible visits will again be addressed opportunistically.

Meteorological Project
  • Two automatic weather stations were deployed in September 2006 near the eastern shore of Ellesmere Island, one on Pim Island and the other at Cape Isabella. Professor Kent Moore of the University of Toronto has asked that we visit these sites to retrieve data recorded during the last year, to assess the continued viability of the installations, and depending on that assessment, to refurbish or retrieve the installations.

CBC Coverage
  • CBC's Sasa Petricic will be joining the CAT expedition for the last few days of work in the vicinity of Cardigan Strait. He will be working on TV coverage of this element of Canada's programme for the International Polar Year.
  • Sasa will film the scientific work in Hell Gate and Cardigan Strait and stay with the ship as it skirts Devon Island and Bylot Island on the way to Pond Inlet (lots of great scenery and wildlife in addition to the scientific activity).

Complete Science Plan --- .PDF 2.4 MB

This material is based upon work supported by the National Science Foundation under Grant No. 0230236. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.