Laurentian Fan Moored Currents DataMay 2006 – May 2007

Part of project “Current Statistics from Deep-Water Drifters and other Measurements in Atlantic Slope Frontier Gas Areas”

Funded by Unconventional Gas Supply Program of the Canadian Climate Technology and Innovation Initiative (CCTII)

Carried out by Fisheries and Ocean Canada (DFO), Bedford Institute of Oceanography

Contact: John Loder (902-426-3146) or Yuri Geshelin (902-426-3584)

John Loder and Yuri Geshelin - 13 June 2008

CCTII Moored Currents Data for Laurentian Fan

2000m

1975m Current Meter

Previous (●) and CCTII (▲) Deployment Sites

Example DFO/CCTII Mooring

CCTII moorings on 1100 and 2000m isobaths from May 2006 to May 2007

RCM11 Current Meter at 25 m above bottom

Site LF-A: 44 45’N, 56 5.5’W - 25 m above bottom in Water Depth of 1104 m

Site LF-B: 44 32.6’N, 56 3.5’W - 25 m above bottom in Water Depth of 2009 m

Comparison of Near-Bottom Currents Speeds at LF-A and LF-B

Site InstrumentDepth (m)

Mean Speed (m/s)

Max Speed (m/s)

LF-A 1079 0.062 0.214

LF-B 1984 0.044 0.238

Statistics of Current Speed at the 2 Sites

Progressive Vector (Drift) Plots from 2006-07

Moored Currents Data

LF-A (1100 m) : Drift of about 2 cm/s towards WSW (expected drift direction)

LF-B (2000 m) : Drift of about 1 cm/s towards SSE

- Weak current drift

- Not understood why drift to SSE instead of SW (possibly a local topography effect)

LF-A (1100 m)

LF-B (2000 m)

Comparison with Currents Speeds in Other Areas

Mean and Maximum Near-Bottom Current Speeds in 1 year records at Sites along the 1100-m and 2000-m isobaths

SS= Scotian Slope

LF= Laurentian Fan

SWGB= SW Grand Bank

FP= Flemish Pass

OB= Orphan Basin

LS= Labrador Slope

1100-m Isobath:

Stronger Means on LS then FP (no data from SWGB)

2000-m Isobath:

Strongest Max on SWGB (no data from FP and LS)

Weakest Currents on Laurentian Fan