1. Introduction

1. 1. Introduction • Paradox: stunning new technologies for observing the subpolar ocean and its impact on global climate yet a bewildering set of questions and an accelerating pace of high-latitude climate change. • Given the limits to new resources, can one now design a pattern of observations ensuring that the most important dynamical trends will in fact be observed in the coming several decades? ‘Generalizing the ocean weather ship’ ‘restarting ASOF’

2. Yashayaev & Loder GRL 2008see also, Våge et al. 2008

4. NADW LSW contributes 56% of the CFC-11 inventory and 72% of the volume flux in NADW (….heat flux, freshwater flux) Lebel et al. DSR 2008 inventory 106 moles formation rate 1970-1997 total NAtl20N-42N EDW 5.4 3.3 Sverdrups ULSW 10.54.23.5 CLSW 23.4 5.88.2 ISOW 10.4 3.1 5.7 DSOW 8.3 4.0 2.2 ____ ____ 56.0 19.6 Sv 33.9 11.7 Yet direct physical measurments seem to give far lower LSW transformation rates (2 Sv, Pickart & Spall JPO 2007) Similar disagreements occur in climate models and high-resolution ocean models.

6. 2 Monday, 10 November: Main Auditorium, BIO Session 1: Workshop Goals and Background 0830: Welcome and Introductions (10 min) – John Loder (BIO) 0840: Workshop Goals and Structure (10 min) – Peter Rhines (UW) 0855: NOAA Perspective (12 min) – John Calder (NOAA) 0910: Overview of DFO Ocean Monitoring and Climate Programs (10 min) – John Loder Session 2: Recent Advances, Key Issues and Planned Programs 0925: IFM Germany Programs (12 min) – Jurgen Fischer 0940: Univ. Bremen Programs (12 min) – Monika Rhein 0955: Inst Sea Fisheries, Hamburg (10 min) – Manfred Stein (given by Eugene Colbourne) 1005: Denmark Meteorological Institute (15 min) – Steffen Olsen 1025-1045: Refreshment Break Session 2 (continued): Advances, Issues and Programs 1045: Influence of the eastern overflows on the Labrador Sea and the AMOC (12 min) – Bogi Hansen (Faroese Fisheries Lab) 1100: Circulation variability and pathways in the subpolar North Atlantic (10 min) – Peter Rhines 1130: Univ Washington in Baffin Bay and Davis Strait (10 min) – Craig Lee 1145: Outflows from Baffin Bay (and Archipelago) (10 min) - Brian Petrie (BIO) 1200: BIO Lab Sea and Downstream Physical Oceanography (12 min) – Igor Yashayaev (BIO) 1215-1315: Lunch Break

7. 3 Monday, 10 November: Main Auditorium, BIO Session 2 (continued): Advances, Issues and Programs 1315: Hydrographic Variability in the NW Atlantic (12 min) – Bob Pickart (WHOI) 1330: Buoyant eddies entering the Labrador Sea, observed with gliders, floats and altimetry (12 min) – Hjalmar Hatun (Faroese FL) 1345: Role of Eddies in the Lab Sea Region (10 min) – Jonathan Lilly (ESP) 1400: Drifters and Exit Pathways in the Lab Sea Region (12 min) – Amy Bower (WHOI) 1415: Tracer Pathways from the Arctic through the NW Atlantic (10 min) – John Smith (BIO) 1430: CO2 and Related Issues in the NW Atlantic (10 min) – Kumiko Azetsu-Scott (BIO) 1445: Newfoundland and Labrador Shelf/Slope Variability from DFO Atlantic Zone Monitoring Program (10 min) – Eugene Colbourne (NAFC) 1500-1515: Refreshment Break Session 2 (continued): Advances, Issues and Programs 1520: Subpolar Gyre influences on NW Atlantic Shelves (10 min) – Brian Petrie 1535: BIO on Lab Sea Biology, Shelf Linkages and ESSAS (15 min) – Erica Head (BIO) 1555: NOAA on Linkages to the AMOC (12 min) – Molly Baringer (NOAA) 1610: POL on RAPID-WATCH (10 min) – Miguel Angel Morales Maqueda (POL) 1625: Observations on Line W (10 min) – Ruth Curry (WHOI) 1640: Discussion

8. 4 Monday, 10 November: Main Auditorium, BIO Session 3: Key Issues and Potential Elements for a Sustained Observation Program 1645: Strawdog Outline from a Dynamical/Process Perspective (5-10 min) – Peter Rhines Climate Change Perspective (5-10 min) – Allyn Clarke Ecosystem Perspective (5-10 min) – Glen Harrison 1715: General Discussion and Plan for Day 2 1730: End of Day 1 Sessions 1815: Cash bar in Harbourside Terrace at Holiday Inn 1915: Complimentary Buffet Dinner in Harbourside Terrace at Holiday Inn

9. 5 Tuesday, 11 November: Hawthorne Room, Holiday Inn Harbourview Session 4: Discussion and Planning 0830-1010: Review of Workshop Objectives and Scientific Topics Discussion of Scientific Topics and Questions Discussion of Relative Importance of Processes 1010-1030: Refreshment Break Session 4 (continued) 1030-1100: Discussion of Scientific Topics, Questions and Processes 1100-1105: Remembrance Day 1105-1200: Discussion of Scientific Issues, Approaches and Opportunities 1200-1215: Discussion of Workshop Outputs and Planning Approach for PM - Report on Findings - Outline of Desirable Program(s) 1215-1315: Lunch Break Session 5: 1315-1500: Development of Workshop Outputs 1500-1515: Refreshment Break 1515-1600: Development of Workshop Outputs 1600: Conclude Workshop 1615-1715: Steering Committee Meeting

10. John Calder questions: 1.  Is there scientific merit in quantifying deep water formation in the Labrador Sea over climate-relevant time scales?  Why?2.  How should such an observation program be implemented?  What are the key variables and effective observation strategies?3.  Are there unknowns or uncertainties that must be clarified before a long-term observation effort should be started?Secondary questions would be:4.  How could fresh water influx to the Labrador Sea be quantified, and how could its effect on deep water formation be determined?5.  How could the ecological impact of physical changes in the Labrador Sea and adjacent areas be determined?We could also use the presentations on day 1 to identify other key questions for discussion on day 2.

18. Heat balance Chanut et al. JPO 2008

28. Våge et al. 2008

31. Subpolar pathways and variabilityP.B.Rhines, U. Washington S. Häkkinen NASA Goddard SFC

32. implications of subpolar gyre decadal (or secular) variability: • post-1994 weakening, and shrinking of SP gyre westward as it weakens (Häkkinen & Rhines Science 2004, Hatun et al. Science 2005) • changing subtropical => subpolar warm-water transport (Häkkinen & Rhines JGR subm. 2008) • control over basal melting of Greenland glaciers (Holland et al. Nature Geo 2008) leading to the Jakobshavn Isbrae acceleration post 1996 • strong decrease in CO2 uptake by northern Atlantic since mid 1990s ( Shuster &Watson GRL 2007). • changing advection of freshwater from Arctic and Greenland sources • strong control over deep convection ‘geography’ (Hatun et al. JPO 2007) • strong control over primary productivity, zooplankton, larger animals, birds (Williams et al. EOS 2008, DSR 2008 • complex interaction with NADW outflow

33. implications of subpolar gyre decadal (or secular) variability: • post-1994 weakening, and shrinking of SP gyre westward as it weakens (Häkkinen & Rhines Science 2004, Hatun et al. Science 2005) • changing subtropical => subpolar warm-water transport (Häkkinen & Rhines JGR subm. 2008) • control over basal melting of Greenland glaciers (Holland et al. Nature Geo 2008) leading to the Jakobshavn Isbrae acceleration post 1996 • strong decrease in CO2 uptake by northern Atlantic since mid 1990s ( Shuster &Watson GRL 2007). • changing advection of freshwater from Arctic and Greenland sources • strong control over deep convection ‘geography’ (Hatun et al. JPO 2007) • strong control over primary productivity, zooplankton, larger animals, birds (Williams et al. EOS 2008, DSR 2008 • complex interaction with NADW outflow

34. ALTIMETRIC SSH CHANGES(update using only TOPEX/Poseidon and Jason-1 data, time period covered: October 1992 to April 2008) (Häkkinen and Rhines; 2004)

35. synthetic drifters based on altimetric surface velocity field Drifter trajectories showing increased communication of subtropical waters to the northern overflow sites since 2000, which reinforce the observations of warming, increased salinity at Iceland-Scotland Ridge and Norwegian Sea drifter data

36. implications of subpolar gyre decadal (or secular) variability: • post-1994 weakening, and shrinking of SP gyre westward as it weakens (Häkkinen & Rhines Science 2004, Hatun et al. Science 2005) • changing subtropical => subpolar warm-water transport (Häkkinen & Rhines JGR subm. 2008) • control over basal melting of Greenland glaciers (Holland et al. Nature Geo 2008) leading to the Jakobshavn Isbrae acceleration post 1996 • strong decrease in CO2 uptake by northern Atlantic since mid 1990s ( Shuster &Watson GRL 2007). • changing advection of freshwater from Arctic and Greenland sources • strong control over deep convection ‘geography’ (Hatun et al. JPO 2007) • strong control over primary productivity, zooplankton, larger animals, birds (Williams et al. EOS 2008, DSR 2008 • complex interaction with NADW outflow

37. Acceleration of Jakobshavn Isbrae triggered by warm subsurface ocean waters, (Holland, Thomas, de Young, Ribergaard & Lyberth Nature Geosciences 2008) “sudden change in 1997”

38. greater than 50% reduction in uptake of CO2 by the ocean 1994-1995 2002-2005 Schuster & Watson GRL 2007

39. implications of subpolar gyre decadal (or secular) variability: • post-1994 weakening, and shrinking of SP gyre westward as it weakens (Häkkinen & Rhines Science 2004, Hatun et al. Science 2005) • changing subtropical => subpolar warm-water transport (Häkkinen & Rhines JGR subm. 2008) • control over basal melting of Greenland glaciers (Holland et al. Nature Geo 2008) leading to the Jakobshavn Isbrae acceleration post 1996 • strong decrease in CO2 uptake by northern Atlantic since mid 1990s ( Shuster &Watson GRL 2007). • changing advection of freshwater from Arctic and Greenland sources • strong control over deep convection ‘geography’ (Hatun et al. JPO 2007) • strong control over primary productivity, zooplankton, larger animals, birds (Williams et al. EOS 2008, DSR 2008 • complex interaction with NADW outflow

40. advection of low salinity surface layer off the west Greenland coast shapes both deep convection region, Labrador Sea Water production and primary spring plankton bloom (Hatun, Eriksen & Rhines 2007 JPO, Wu et al. Mar Eco Prog 2008, Williams et al. DSR 2008 subm, EOS 2008) black contours: Lavender ARGO streamfunction grey shades: altimetric EKE colors: depth of winter convection in 1968. from Pickart et al. 2002)

41. Vage et al. 2008 max MLD 2008

42. Cold shelf water (purple) streams off the Greenland shelf. Seagliders 014 and 015 are embedded in this jet Aqua & Terra satellite SST day 089 05

43. two Seagliders patrolling the outflowing low-salinity water from Greenland,and its explosive spring plankton bloom (Hatun et al.2007, Williams et al 2008) SeaWiFS satellite: oceanic surface phytoplankton 2005 days 91-120

44. ARGO float trajectories (Eleanor Williams)

45. SeaWiFS ocean color Apr 29-May18 2005 and Seaglider 0-5m salinity, 2003-5 (Williams et al., DSR subm 2008)

46. Williams, Rhines & Eriksen 2008 DSR subm

49. implications of subpolar gyre decadal (or secular) variability: • post-1994 weakening, and shrinking of SP gyre westward as it weakens (Häkkinen & Rhines Science 2004, Hatun et al. Science 2005) • changing subtropical => subpolar warm-water transport (Häkkinen & Rhines JGR subm. 2008) • control over basal melting of Greenland glaciers (Holland et al. Nature Geo 2008) leading to the Jakobshavn Isbrae acceleration post 1996 • strong decrease in CO2 uptake by northern Atlantic since mid 1990s ( Shuster &Watson GRL 2007). • changing advection of freshwater from Arctic and Greenland sources • strong control over deep convection ‘geography’ (Hatun et al. JPO 2007) • strong control over primary productivity, zooplankton, larger animals, birds (Williams et al. EOS 2008, DSR 2008 • complex interaction with NADW outflow