QuickTime™ and aPNG decompressor

are needed to see this picture.

The goal of the SBI global change project is to investigate the production, transformation and fate of carbon at the shelf-slope interface in the Arctic as a prelude to understanding the impacts of a potential warming of the Arctic

Western Arctic Shelf-Basin Interactions(SBI):a NSF/ONR Global Change Project

Overall hypothesis: climate change will significantly and preferentially impact the physical and biological linkages between arctic shelves and the adjacent ocean basins

Focus area: • Chukchi and Beaufort seas and slopes

• outer shelf, shelf break and upper slope, where key processes control water mass exchange and biogeochemical cycles

• greatest responses to climate change are expected

SBI Overall Hypothesis and Focus

SBI Phase Timeline

The SBI project is progressing in three phases over a 10-year period.

Phase I (1998-2001) completed and involved analysis and synthesis of

historical data, opportunistic field investigations, and modeling of

specific regions and processes (31 PIs, 18 projects)

Phase II (2002-2006) constituted the field program, which took place in

the Bering Strait region and over the outer shelf, shelf break and upper

slope of the Chukchi and Beaufort seas (40 PIs, 14 projects)

Phase III (2007-2009) will focus on development of Pan Arctic models

suitable for simulating scenarios of the impacts of climate change on

shelf-basin interactions (10 PIs, 5 projects).

The SBI Phase II field project was centered around three research foci in the core study area in the Chukchi and Beaufort seas:

Northward fluxes of water and bioactive elements through the Bering Strait input region

Seasonal and spatial variability in the production and recycling of biogenic matter on the shelf-slope area

Temporal and spatial variability of exchanges across the shelf/slope region into the Canada Basin

USCGC HEALY

USCGC POLAR STARSEA

RVALPHA HELIX

SBI Field Program2002 and 2004

USCGC HEALY

May-June (Nome-Nome, AK)-process

July-August (Nome-Nome, AK)-process

USCGC POLAR STAR

July-August (Dutch Harbor-return, AK)

RV ALPHA HELIX

June (Dutch Harbor-Nome, AK)

2003

RV Nathaniel B. Palmer

July-August (Nome/Dutch Harbor)-survey

USCGC POLAR STAR

September-October (Dutch Harbor)

RV ALPHA HELIX

June

USCGC POLAR STAR

RV ALPHA HELIX

SBI Phase II-Field Program

SBI Phase II-Field Program

ARCARCSSS relevant issues related to warming in the western Arctic OceanS relevant issues related to warming in the western Arctic Ocean- ecosystem change, including whale migration / feeding habit changeecosystem change, including whale migration / feeding habit change- human aspects: native community subsistence and culturehuman aspects: native community subsistence and culture- increased human presence: new transportation routes, natural resource explorationincreased human presence: new transportation routes, natural resource exploration- potential global consequences of freshwater export from the Arctic Ocean- potential global consequences of freshwater export from the Arctic Ocean

Observed September sea ice extent 1979-2005Observed September sea ice extent 1979-2005

Rate of decline• 1979-2001: 6.5 % per decade• 1979-2005: 8 % per decade

96-05 trend ~21% per decade?96-05 trend ~21% per decade?96-05 trend ~21% per decade?96-05 trend ~21% per decade?

Significant and Significant and acceleratedaccelerated decrease in sea ice extent in decrease in sea ice extent in the late 1990s and 2000s. the late 1990s and 2000s.

Note that largest changes Note that largest changes are at inflows of Pacific / are at inflows of Pacific / Atlantic water into the Atlantic water into the Arctic Ocean and during Arctic Ocean and during SBI field programs.SBI field programs.

09/87 09/02 09/05

Bering/Chukchi/Beaufort Sea

Marginal Ice Zone System

Fluxes of heat, salt, Fluxes of heat, salt, freshwater, nutrients freshwater, nutrients through Bering Strait through Bering Strait and their seasonal and their seasonal and inter-annual and inter-annual variability strongly variability strongly influence the influence the Western Arctic Western Arctic ecosystemecosystem

[Woodgate et al. 2005; [Woodgate et al. 2005; Clement et al. 2005]Clement et al. 2005]

[courtesy W. Maslowski]

HVWHS

EHS

BC

EB

Modeled Sea Surface (0-5 m) Salinity (ppt), Velocity (cm/s)and Sea Ice Concentration (% - red contours) -

Mean August 1979-1981

- Heat content of surface waters: above - Heat content of surface waters: above 50 m depth sufficient to melt 10-100 cm 50 m depth sufficient to melt 10-100 cm thickness of sea icethickness of sea ice- Studies (both field and modeling) are - Studies (both field and modeling) are needed to understand effects of Pacific needed to understand effects of Pacific Water advection from Bering Strait into Water advection from Bering Strait into the Arctic Ocean and its effect on the the Arctic Ocean and its effect on the environmentenvironment

Increased Pacific water heat fluxes into the Arctic Ocean1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 20040

5

10

15

20

Monthly mean

Heat Flux (TW)

Bering Strait (upper 120 m) heat flux (net direction is North)

2.331

Net Net (13-mo.) Mean

1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 20040

1

2

3

4

Monthly mean

Heat Flux (TW)

Chukchi Shelf Line (upper 120 m) heat flux (net direction is North)

0.142

Net Net (13-mo.) Mean

1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004

-0.05

0

0.05

0.1

0.15

Monthly mean

Heat Flux (TW)

Wrangel To Basin (upper 120 m) heat flux (net direction is East)

0.003

Net Net (13-mo.) Mean

1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004-1.5

-1

-0.5

0

Monthly mean

Heat Flux (TW)

Canadian Archipelago (upper 120 m) heat flux (net direction is South)

-0.321

Net Net (13-mo.) Mean

1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004

-0.02

-0.01

0

0.01

Monthly mean

Heat Flux (TW)

East Siberian Shelf Line (upper 120 m) heat flux (net direction is South)

0

Net Net (13-mo.) Mean

She

baS

heba

She

baS

heba

EBC – Aug 2002

- IncreasedIncreased modeled modeled northward heat flux northward heat flux off the Chukchi Shelf off the Chukchi Shelf correlatescorrelates with the with the recent ice retreat in recent ice retreat in the Western Arcticthe Western Arctic (cor. coef. = 0.7-08)(cor. coef. = 0.7-08)

[Courtesy of W. Maslowski][Courtesy of W. Maslowski]

[SBI Hydrography Data Team (Codispoti, Swift et al.)][SBI Hydrography Data Team (Codispoti, Swift et al.)]

[Courtesy of W. Maslowski][Courtesy of W. Maslowski]

Summer 2004 - Abandoned Walrus Calves

• Nine walrus calves observed in deep ice-free waters, apparently abandoned by mothers• Calves of this age are still nursing and dependent on their mothers• Walrus need ice to rest and to be over shallow water so they feed on the benthos• Rapid retreat of ice because of a) very warm Pacific Water, b) wind, or c) a combination• Calves may not have been able to keep up with their mothers as the ice edge retreated

Cooper, Ashjian, Smith, Codispoti, Grebmeier, Campbell, Sherr 2006 - Aquatic Mammals

NCEP reanalysis forwestern Arctic

22 upwelling events between22 upwelling events betweenSeptember 2002 and May 2003! September 2002 and May 2003!

Diagnosing an upwelling event in the western Arctic: Cross-stream fluxes of mass and properties [R. Pickart et al.]

Atmospheric LinkagesWhich storms trigger upwelling?

Upwellingfavorable

Noupwelling

Primary production and optical findings in the SBI regionPrimary production and optical findings in the SBI region

• Barrow Canyon high productivity, reaching 8.8 g C Barrow Canyon high productivity, reaching 8.8 g C mm-2-2 d d-1 -1

• High particle export to slope, basin?High particle export to slope, basin?

System relevanceSystem relevance: High levels of colored dissolved : High levels of colored dissolved organic material (CDOM) were observed which organic material (CDOM) were observed which would increase energy absorption in the surface would increase energy absorption in the surface waters by 40% over clearest natural waters thus waters by 40% over clearest natural waters thus impacting on heating, albedo impact and positive impacting on heating, albedo impact and positive feedback to further ice meltfeedback to further ice melt

[Hill and Cota, 2005]

Sea Area (103 km2) Depth (m) PP (gC/m2 yr)

Barents 1512 200 20-200

White 85 56 25

Kara 926 131 30-50

Laptev 498 48 25-40

East Siberian 987 58 25-40

Chukchi 620 80 20-400

Beaufort 178 124 30-70

Lincoln 64 257 20-40

Shelf N. Can. Arc. Archipelago

146 338 20-40

Shelf NE Greenland

30 119 20-40

Shelf NW Svalbard

6 93 20-40

[E. Sakshaug 2004]

Sediment community oxygen consumption (mmol O2 m-2 d-1) from 1984-2004

• an indicator of carbon supply to the underlying benthos, persistent patterns of carbon flux to sediments

• yet time series stations in “hot spots” (black box) indicate decline in carbon supply and benthic standing stock [Grebmeier et al. 2006, Science]

[Data maps from Grebmeier et al. 2006, Prog. Oceanogr., accepted]

Macrofaunal biomass (g C m-2) from 1977-2004

• identify “foot prints” of high carbon deposition and benthic biomass on the shallow continental shelves for time series investigations embedded in periodic process studies

Pelagic-benthic coupling: SBI I and II results

Large Horizontal Export of POM at BC

Barrow Canyon (BC) sectionBarrow Canyon (BC) section

[Bates et al., 2005a; Moran et al. 2005][Bates et al., 2005a; Moran et al. 2005]

Much of the productivity Much of the productivity occurring in this region occurring in this region of the Chukchi Sea of the Chukchi Sea shelf was:shelf was:-exported laterally, with exported laterally, with plumes of suspended plumes of suspended POM in the upper POM in the upper halocline observed off-halocline observed off-shelf extending into the shelf extending into the Arctic Ocean basin Arctic Ocean basin (Bates et al., 2005),(Bates et al., 2005),

or or - vertically exported to vertically exported to the sea floor (Moran the sea floor (Moran et et alal., 2005).., 2005).

LargeLargePOCPOC

LargeLargePONPON

LHWLHW

UHWUHW

SBI Catalog Products Samples

NCAR/EOL: (http://www.eol.ucar.edu/projects/sbi/)

Remote observations

Multiple Data SetsBathymetry hydrography

Plan for SBI DSR 2nd volume-deadline fall 2006 (Eds. Grebmeier, Harvey and Stockwell)

SBI Special Issue One - 23 papers

ARCSS Synthesis

Currently ARCSS program is advancing toward an integrated understanding of the system by focusing explicitly on questions that link multiple system components and processes across a range of temporal and spatial scales through:

• Focus on interdisciplinary, cross-cutting questions that will lead to a better understanding of how the system components function and interact

• Demonstrate relevance to the entire arctic system, and if possible, relevance of the arctic system within the broader Earth system.

• Incorporate existing arctic data, information, and models

[http://www.arcus.org/ARCSS/index.html and current ARCSS AO]

AtmosphericForcing

Shelf Carbon CycleBering Strait

Inflow

CarbonStorage

Sea Ice Cover

Solar Insolation

GlobalCirculation

Upper Trophics

Humans

ClimateFeedbacks

Examples of linkages between Shelf – Basin InteractionsExamples of linkages between Shelf – Basin Interactionsand the and the Arctic SystemArctic System

Land-hydrology-seainterface

Shelf-BasinExchange

IR image of an Aleutian lowon January 3, 2001

Storm Climate of the Western Arctic and its Impact on Shelf-Basin Exchange

Motivation

•Warmer climate means more frequent and more powerful storms.•Wind forcing has major impact on shelf-basin exchange of heat, salt, nutrients, and carbon.•Requires a system-wide approach encompassing scales from 10 km to 1,000 km.

Approach

Use a mix of meteorological fields (NCEP), a high resolution atmospheric model (WRF), a regional ocean –ice model (MIT), and SBI mooring/shipboard data to investigate:

•Role of storm development, ice field, orography, coastline, and bathymetry in driving cross-stream exchange in past and present storm climates.

•Possible impacts of shrinking ice cover and warmer inflow through Bering Strait in altering future such wind-driven exchange.

R.S. Pickart Woods Hole Oceanographic InstitutionM.A. Spall Woods Hole Oceanographic InstitutionG.W.K. Moore University of TorontoJ.T. Mathis University of Alaska, Fairbanks

Determining the Present and Future Ocean Carbon Dynamics in the Chukchi Sea and Pan-Arctic Ocean: SBI Phase III Activities

Nicholas Bates, Bermuda Institute of Ocean Sciences (BIOS), BermudaJeremy Mathis, University of Alaska at FairbanksDennis Hansell, RSMAS, University of MiamiBradley Moran, University of Rhode Island

Objective 1: Determine stocks of inorganic and organic carbon in the Chukchi Sea and pan-Arctic (e.g., anthropogenic CO2);Objective 2: Determine rates, including air-sea CO2 gas flux, net community production, and export production on the Chukchi and other shelves, and adjacent Arctic Ocean basin;Objective 3: Synthesize rates and stocks using carbon mass balance approaches. This effort includes comparative analyses of the Chukchi shelf with other shelves (carbon cycling on inflow versus interior shelves) and anticipated changes in the Arctic carbon cycle.

SBI Phase III Collaborative Project (NYU/Stanford):A Modeling Comparison of the Alaskan and Mackenzie Shelves

Project Tasks:

A thorough analysis and intercomparison of two physical, chemical,and biological oceanographic data sets for adjacent, but unique Arctic shelves will be performed,allowing for an improved understanding of the universal and non-universal properties of polar shelfecosystems.

A coupled physical, chemical, and biological model of the two specific Arctic shelvesand their nesting inside a pan-Arctic computer model will allow us to better understand the presentfunction of these shelves, as well as their future behavior in the larger changing Arctic environment.

Investigators:D. Holland (PI, NYU)

T. Reddy (Postdoc, NYU)K. Arrigo (PI, Stanford)

CASES Data Set RegionSBI Data Set Region

October 2, 2008ARCSS Synthesis Workshop

Effect of a warming climate on Arctic shelf and basin Calanus populations: implications for Pan-Arctic ecosystem dynamics

Carin J. Ashjian, Cabell S. Davis, Rubao Ji, Robert C. Beardsley(WHOI); Robert G. Campbell (URI); Changsheng Chen, Geoffrey W. Cowles (UMass Dartmouth)

• Use biological-physical coupled models and numerical experimentation:

– To explore the physical and biological factors that control Calanus population dynamics and biogeographic boundaries

– To investigate the impacts of climate warming on Calanus mediated regime shifts in these systems.

• Three particular regions of focus: Chukchi Sea, Barents Sea, Arctic Basin

Copepods of the genus Calanus are the keystone pelagic species in Arctic pelagic ecosystems.

NCAR/EOL: (http://www.eol.ucar.edu/projects/sbi/)

Remote observations

Bathymetry hydrography

Shelf-Basin Interactions Phase III Data Management (SBI III)James Moore and Steve Williams

University Corporation for Atmospheric Research, Boulder, CO

The National Center for Atmospheric Research (NCAR) Earth Observing Laboratory (EOL) will develop and implement a comprehensive data management strategy for Phase III of the Western Arctic Shelf Basin Interactions (SBI) Project in cooperation with the SBI Project Office (SBI-PO), the investigators who will provide datasets and information, as well as other collaborating projects. An integrated data management activity will ensure that a complete database is provided with easy access by all project investigators and the science

community in general.