seafloor mapping in the high arctic: the challenges and ...1).pdf · seafloor mapping in the high...

Arctic Change Quebec CityArctic Change Quebec City 11 Dec 200811 Dec 2008

Seafloor Mapping in the Seafloor Mapping in the High Arctic: High Arctic:

Center for Coastal and Ocean Mapping / NOAACenter for Coastal and Ocean Mapping / NOAA--UNH Joint Hydrographic Center University of UNH Joint Hydrographic Center University of

New Hampshire, USANew Hampshire, USA

The Challenges and the JoysThe Challenges and the JoysLarry MayerLarry Mayer

Martin Martin JakobssonJakobssonDept of Geology and Dept of Geology and GeochemsitryGeochemsitry

Stockholm UniversityStockholm University

A geospatial context for our studies of Arctic change

Nansen 19071893-1896

8 soundings….

Fletcher’s Ice Island (TFletcher’s Ice Island (T--3)3)

Positioning

1962 1962 -- 19741974LOREX LOREX -- 19791979

Hydro-Hole

Echo sounder

Airborne Measurements and Point Soundings

Gravity Measurement

MagnetometerDepth Sounding

CHS & GEBCO (1967,1968,1979)

Data from Nuclear SubmarinesData from Nuclear Submarines

Sounding tracks of US Navy submarines from 1983 to 1988 Sounding tracks of US Navy submarines from 1983 to 1988 (from Bob Anderson via NGDC).(from Bob Anderson via NGDC).

http://www.ldeo.columbia.edu/res/pi/SCICEX/

SCICEX (1993-1997)

http://www.oceandata.com/images/11hrsbp.jpg

IBCAO 1999

IBCAO 1999

UNCLOS

The Drivers

Climate Change

United Nations Convention United Nations Convention on the Law of the Sea on the Law of the Sea

Article 76Article 76Six hundred and seventeen words that redefine the “continental shelf” of a coastal state and provide a mechanism for the state to extend its sovereign rights over the resources of the “seabed and subsoil” of the continental shelf

UNCLOS Article 76UNCLOS Article 76

•• A coastal state is entitled to sovereign rights over the resources of the seabed and subsoil of "submerged extensions of the continental margin" beyond their 200 nm Exclusive Economic Zone (EEZ) if….

•• Demonstrate a “natural prolongation” of the coastal state’s territorial landmass

typically broad continental shelf and/or

thick sedimentary wedge

The ProcessThe Process

• All coastal states are entitled to a 200 nm EEZ

Data RequiredData Required

•• Once the natural prolongation is established the extended continental shelf beyond the 200 nm EEZ is determined by a set of formulae and limit lines defined from the:

• depth and shape of the seafloor

• the thickness of the underlying sediments

• distances from the territorial sea baselines

(FOS and 2500m contour)(FOS and 2500m contour)

(1% line)(1% line)

(350 nm line)(350 nm line)

Need to map the seafloor

UNH CCOMUNH CCOM--JHC U.S. LawJHC U.S. Law--ofof--thethe--Sea Bathymetric Sea Bathymetric Mapping to DateMapping to Date

Mayer et al. 2002 U.S. Law-of-the-Sea Desktop Study

Marianas2006

20082008

Kingman Reef-Palmyra Atoll

soon

soon

…..Arctic2003

Bering Sea2003

…Atlantic20042004

Gulf of Mexico2007

2007

2007Gulf of Alaska

2005

2005

Arctic is unique as an ocean basin in that >52% is made up of shelf (geologic)

SemiSemi--enclosed basin with five enclosed basin with five nations having potential extended nations having potential extended

shelvesshelves

From Ron McNab

From Durham University

Session T12

Law and Politics of Canadian

Jurisdiction on the Arctic Ocean

Seabed

Single Beam Echo SounderSingle Beam Echo Sounder

MultibeamMultibeamEcho SounderEcho Sounder

A new perspective A new perspective new insightsnew insights

Arctic - Chukchi Plateau mappingUSCGC Healy

Larry

Seabeam 2112 - 12 kHz, 121-2˚ receive beamsbathymetry & acoustic backscatterKnudsen 320BR 3.5-kHz chirp profiler

UNH: bathymetry, backscatter & 3.5-kHz processing at sea

Andy

Chukchi plateau

Barrow margin

2003 & 20042007 & 2008

operations…………….……... 65 daystransits……………………..… 24 daysaverage speed (in ice)……...4 ktsaverage sea-ice state………..…9/10tracklines………………… ~24,300 km Area mapped…….…. ~135,000 km2

Arctic Mapping 2003,2004,2007,2008

cruise statistics

Healy 03Healy 03--0202

~3000 km of ~3000 km of multibeammultibeam

sonar sonar bathymetrybathymetry

11--11 Sept 0311 Sept 03

8/10 ice8/10 ice

typical ice conditions2003

8/10 “cheesy” ice

Redefinition of the 2500 m contour

3100 m high, summit at 900 m water depth

Healy SeamountHealy Seamountlooking S, looking S, veve=6x=6x

45 km long x 15 km wide

water depth (m)

Healy Seamount SurveyHealy Seamount Survey

Radarsat ice coverage for 10 October 2004. Image processed at either ASF, Qinetic or CDPF. © CSA2004

2004

Chukchi plateau

Grönland

How do we map in this?

HEALY 04-05 TRACK

6-26 Oct. 2004

6700 line km

“Ratchet Surveying”

“Pirouette Surveying”

Barrow marginlooking SE, ve=10x

2500 m

ridges<300 m high,~100 km long

erosionN

mapped 2500-m isobath

HEALY 07HEALY 07--0303Depart Barrow:Depart Barrow:

17 Aug. 0717 Aug. 07Return BarrowReturn Barrow15 Sept. 0715 Sept. 07

72°N

75°N

78°N

81°N

HEALY HEALY 07030703

mapping the2500-m isobath &foot of the slope

perspective view looking SW

2007 results

HealyHealy 0303--02, 0402, 04--05, 0705, 07--0303

HEALY 0805 HEALY 0805 –– SHIPTRACK AND DREDGE SITESSHIPTRACK AND DREDGE SITES

HEALY 0806 and LOUIS St. LAURENT WORKHEALY 0806 and LOUIS St. LAURENT WORK

Pt Barrow

2003, 2004 & 2007Arctic surveys

0 500 km

scours& bedforms

Barrow margin

λ = ~2 kmH = ~10 m

A

B

3 to 5 m deep

central ChukchiPlateau

A B

ice grooves

-380 m

-470 m

Pt Barrow

2003, 2004 & 2007Arctic surveys

0 500 km

pockmarks

Barrow margin

central Chukchi Plateau pockmarks

VE = 10xlooking SW

200-m diameter20-m deep

Lomon

osov

Ridg

e

YermakPlateau

Morris Jesup Rise

Alph

a-M

ende

leev

ChukchiBorderland

Multibeam mapping

R/V Polarstern

I/B Oden

USCGC Healy

Gakke

l Rid

ge

Mackenzie

E u

r a s

i a

n S

h e

l f

S e

a s

CCGS Amundsen

Canadian

Archipelago

• Click to edit Master text styles– Second level

• Third level– Fourth level

» Fifth level

Glacial Sole Marks

5 km

Amundsen Gulf

From S. Blasco

Gary Knolls Mud Volcanoes

Beaufort Sea

From S. Blasco

Shelf Slump

Western EdgeEastern Edge

Beaufort Shelf

From S. Blasco

More at session T34 –Seafloor Mapping of the

Arctic Ocean - Room 207

0º 45ºE 90ºE

135º45ºW

135ºW 180ºE90ºW

IODP Leg 302

SCICEX 99

AMORE, Healy/Polarstern

LOMROG 2007

HOTRAX 2005

Polarstern

Jakobsson 1999, Marine Geology

Polyak et al. 2002, Nature

Jakobsson et al. 2005, QSR

Kristoffersen & Mikkelsen 2006, Marine Geol.

Polyak et al., 2002, Nature

Morris-Jessup Rise

Nansen 1907IBCAO 2008

~~6 % OF THE ARCTIC 6 % OF THE ARCTIC OCEAN HAS BEEN MAPPED OCEAN HAS BEEN MAPPED

WITH MULTIBEAMWITH MULTIBEAM

THERE IS MUCH MUCH THERE IS MUCH MUCH MORE TO DISCOVER!!!MORE TO DISCOVER!!!

www.ccom.unh.eduwww.ccom.unh.edu

Bathymetric CompilationBathymetric Compilation

IBCAO (2002)IBCAO (2002)

??

??

??Resources of extended U.S. continental shelf Resources of extended U.S. continental shelf estimated to be worth 1.3 TRILLION $estimated to be worth 1.3 TRILLION $

MurtonMurton, B.J, Parsons, L.M., Hunter, P. and Miles, P., 2001, , B.J, Parsons, L.M., Hunter, P. and Miles, P., 2001, Global nonGlobal non--living resources on the living resources on the thethe extended continental extended continental shelf: Prospects at the year 2000, Intl. Seabed Authority shelf: Prospects at the year 2000, Intl. Seabed Authority Tech. Study No 1Tech. Study No 1