LIVE INTERACTIVE LEARNING @ YOUR DESKTOP

Thursday, May 20, 2010

RAGEing WISSARDS Study Ice Sheets in a Warming World

Presented by Dr. Ross Powell & Dr. Reed Scherer

Ross Powell & Reed SchererSridhar Anandakrishnan, Andrew Fisher, Helen

Fricker, David Holland, Huw Horgan, Robert Jacobel,

Slawek Tulaczyk

Ross Powell & Reed SchererSridhar Anandakrishnan, Andrew Fisher, Helen

Fricker, David Holland, Huw Horgan, Robert Jacobel,

Slawek TulaczykPhoto: Huw Horgan

RAGESRAGESRAGESRAGES

RAGEing RAGEing WISSARDS Study WISSARDS Study Ice Sheets in a Ice Sheets in a Warming WorldWarming World

RAGEing RAGEing WISSARDS Study WISSARDS Study Ice Sheets in a Ice Sheets in a Warming WorldWarming World

WHAT IS A WHAT IS A

““RAGING RAGING WISSARD”?WISSARD”?

WHAT IS A WHAT IS A

““RAGING RAGING WISSARD”?WISSARD”?

WISSARDWhillans Ice Stream Subglacial Access Research

Drilling

An Integrated Study of Marine Ice Sheet Stability and Subglacial Life Habitats in West Antarctica

2009-2015

WISSARDWhillans Ice Stream Subglacial Access Research

Drilling

An Integrated Study of Marine Ice Sheet Stability and Subglacial Life Habitats in West Antarctica

2009-2015RAGES: Robotic Access to Grounding-zones for Exploration and Science

Focus: stability of ice stream grounding zones

LISSARD: Lake and Ice Stream Subglacial Access Research Drilling

Focus: role of subglacial lakes in controlling ice stream dynamics and mass balance

GBASE: GeomicroBiology of Antarctic Subglacial Environments

Focus: metabolic and phylogenetic diversity of micro-organisms and the associated biogeochemical transformations

RAGES: Robotic Access to Grounding-zones for Exploration and Science

Focus: stability of ice stream grounding zones

LISSARD: Lake and Ice Stream Subglacial Access Research Drilling

Focus: role of subglacial lakes in controlling ice stream dynamics and mass balance

GBASE: GeomicroBiology of Antarctic Subglacial Environments

Focus: metabolic and phylogenetic diversity of micro-organisms and the associated biogeochemical transformations

WISSARD Team (14 PIs, 9 Institutions)WISSARD Team (14 PIs, 9 Institutions)

Slawek TulaczykSlawek TulaczykLISSARD Lead PILISSARD Lead PIRAGES PIRAGES PI

Ross PowellRoss PowellRAGES Lead PIRAGES Lead PILISSARD PILISSARD PI

John PriscuJohn PriscuGBASE Lead PIGBASE Lead PI

Jill MicuckiJill MicuckiGBASE PIGBASE PI

Brent ChristnerBrent ChristnerGBASE PIGBASE PI

Andrew MitchellAndrew MitchellGBASE PIGBASE PI

Andrew FisherAndrew FisherLISSARD/RAGES PILISSARD/RAGES PI

Jeff SeveringhausJeff SeveringhausLISSARD PILISSARD PI

Helen FrickerHelen FrickerLISSARD/RAGES PILISSARD/RAGES PI

Reed SchererReed SchererLISSARD/RAGES PILISSARD/RAGES PI

David HollandDavid HollandRAGES PIRAGES PI

Robert JacobelRobert JacobelRAGES/LISSARD PIRAGES/LISSARD PI

Sridhar AnandakrishnanSridhar AnandakrishnanLISSARD/RAGES PILISSARD/RAGES PI

Mark ScidmoreMark ScidmoreGBASE PIGBASE PI

Funding SupportFunding Support

Design, Development, Construction and OperationsDesign, Development, Construction and Operations

Integrated glaciological, geological, physical, chemical, biological/genomic measurements

3 subglacial environments connected by water: - oceanic environment in the cavity under an ice shelf

- wet subglacial and grounding-zone wedge sediments

- subglacial lake

Integrated glaciological, geological, physical, chemical, biological/genomic measurements

3 subglacial environments connected by water: - oceanic environment in the cavity under an ice shelf

- wet subglacial and grounding-zone wedge sediments

- subglacial lake

WHERE?WHERE?WHERE?WHERE?

• Highest continentHighest continent• Coldest continentColdest continent• Driest continentDriest continent• Biggest ice sheet Biggest ice sheet &&

ice shelvesice shelves• Continent Continent surrounded surrounded

by sea ice by sea ice

AA

BB

ANTARCTICAANTARCTICAANTARCTICAANTARCTICA

What is the difference between an ice sheet and an ice shelf ?

A) An ice shelf exists over land, an ice sheet exists over the oceanB) An ice shelf exists over the ocean, an ice sheet exists over the landC) An ice sheet is a thin glacier, an ice shelf is a thick glacier

What is the difference between an ice sheet and an ice shelf ?

A) An ice shelf exists over land, an ice sheet exists over the oceanB) An ice shelf exists over the ocean, an ice sheet exists over the landC) An ice sheet is a thin glacier, an ice shelf is a thick glacier

The Antarctic Ice Sheet is divided into The Antarctic Ice Sheet is divided into two: the East and West Antarctic Ice two: the East and West Antarctic Ice

SheetsSheets

Question 1Question 1: Which is : Which is more sensitive to more sensitive to climate change, EAIS or climate change, EAIS or WAIS?WAIS?

Question 2Question 2: Why? : Why?

Subglacial lake & grounding zone linked

by ice, sediment, water, biology

Subglacial lake & grounding zone linked

by ice, sediment, water, biology

Most likely flow path of lake discharge water

Fricker, pers. comm.

Most likely flow path of lake discharge water

Fricker, pers. comm.

WHY STUDY THE WHY STUDY THE ICE SHEET ICE SHEET

GROUNDING GROUNDING ZONE?ZONE?

WHY STUDY THE WHY STUDY THE ICE SHEET ICE SHEET

GROUNDING GROUNDING ZONE?ZONE?

Rising Sea Rising Sea LevelLevel

NASA

Sea level history over the past 450,000 Sea level history over the past 450,000 yearsyears

Lambeck et al., 2002, based on tropical & subtropical Lambeck et al., 2002, based on tropical & subtropical recordsrecords

TODAY

Last interglacial

Fu

ll G

lacia

l

Global Sea Level

NASA imagesNASA images

TodayToday

Last ice ageLast ice age

Last 24,000 yearsLast 24,000 years 9,000 years9,000 years 15 years 15 years

• Overall 10-20cm rise inOverall 10-20cm rise in 20th century20th century

• Accepted value of 1.7Accepted value of 1.7 ±0.3mm/yr 20±0.3mm/yr 20thth centurycentury

• 1950-2000 1950-2000 1.8±0.3mm/yr1.8±0.3mm/yr

Sea-Level Forecast: IPCC 2001 & Sea-Level Forecast: IPCC 2001 & 20072007

40cm (1.25ft) rise by 2100, 40cm (1.25ft) rise by 2100, 1m (3.3ft) by 2200 1m (3.3ft) by 2200 IPCC 2001 error estimate: 20-IPCC 2001 error estimate: 20-80cm 80cm

http://www.realclimate.org/images/sealevel_1.jpghttp://www.realclimate.org/images/sealevel_1.jpg

2007200720012001

IPCC 2007 error: 20-60cm IPCC 2007 error: 20-60cm (does not include ice sheet (does not include ice sheet

melting)melting)

Let’s Pause Two Minutes for Questions?

WHAT IS CAUSING WHAT IS CAUSING SEA-LEVEL RISE?SEA-LEVEL RISE?

WHAT IS CAUSING WHAT IS CAUSING SEA-LEVEL RISE?SEA-LEVEL RISE?

Observations: Domingues et al., Nature 453, 1090-1093, Observations: Domingues et al., Nature 453, 1090-1093, 20082008

Model: Hansen et al., Science 308, 1431-1435, 2005Model: Hansen et al., Science 308, 1431-1435, 2005

Thermal ExpansionThermal Expansion

Ocean has gained heat in 20th century ~0.6°COcean has gained heat in 20th century ~0.6°C

Warmer water less denseWarmer water less dense

1.6 mm/yr sea-level rise1.6 mm/yr sea-level rise

Muir Glacier, Muir Glacier, Glacier Bay, Glacier Bay, AlaskaAlaska

Glaciers are shrinking world-wideGlaciers are shrinking world-wide

Antarctica holds what percentage of Antarctica holds what percentage of the worlds fresh water ?the worlds fresh water ?

A) 30%A) 30%B) 50%B) 50%C) 70%C) 70%D) 90%D) 90%

… … but how much but how much waterwater

is in ice sheets?is in ice sheets?

2-6% of all water2-6% of all wateron Earthon Earth

70-80% of all fresh water 70-80% of all fresh water on Earthon Earth

Today

Bindschadler, 1998

3-5m sea3-5m sealevel riselevel rise

~60m ~60m seasealevel riselevel rise

nonenone

EastEastEastEast WestWestWestWest

How much waterHow much wateris in ice sheets?is in ice sheets?

aps

Se a Le v e l Equiv ale nt

1m Sea Level Rise in the New York City 1m Sea Level Rise in the New York City AreaArea

Sea Level Rise and Population at Sea Level Rise and Population at Risk in Southeastern U.S.Risk in Southeastern U.S.

Sea Level Rise Sea Level Rise in Metersin Meters

Population Population Affected in Affected in

MillionsMillions

11 33

22 5.55.5

33 99

44 1313

55 1717

66 1919

A big concern isA big concern issea-level rise from sea-level rise from

ice sheets -ice sheets -Greenland, Greenland, AntarcticaAntarctica

Rowley et al., 2007Rowley et al., 2007

If all of the ice meltsIf all of the ice melts

How long will it take?How long will it take?

Will sea-level rise Will sea-level rise be like this?be like this?

No !No !

Gradual sea-level rise Gradual sea-level rise and storm events and storm events

causing this?causing this?

Highly likely!Highly likely!

(from The Day After Tomorrow)(from The Day After Tomorrow)

Storm SurgesStorm Surges

Add to the rising Add to the rising sea level effectsea level effect

Locally raises coastal sea Locally raises coastal sea level during stormslevel during storms

Right front quadrantRight front quadrant

New Orleans in problems New Orleans in problems

- already below sea level then - already below sea level then add sea level rise + storm add sea level rise + storm

surgessurges

Let’s Pause Two Minutes for Questions?

WHY ARE ICE WHY ARE ICE SHELVESSHELVES

IMPORTANT HERE?IMPORTANT HERE?

WHY ARE ICE WHY ARE ICE SHELVESSHELVES

IMPORTANT HERE?IMPORTANT HERE?

Ice shelves are Ice shelves are importantimportant

help protect ice sheetshelp protect ice sheets

Last decades...Last decades...

decreased salinity and increased decreased salinity and increased sea water temperatures beyond sea water temperatures beyond Antarctic ice shelves indicate Antarctic ice shelves indicate their melting is increasingtheir melting is increasing

Jacobs et al. (2002)Jacobs et al. (2002)

Salin

ity

Tem

pera

ture

oC

summerwinter

Vulnerable elements of Antarctic cryosphere under Vulnerable elements of Antarctic cryosphere under warmingwarming

Morris and Vaughan, Morris and Vaughan, 20042004

-5oC

Ice shelves lost 14,000 Ice shelves lost 14,000 kmkm22

Larsen Ice Shelf breaks up catastrophically in Larsen Ice Shelf breaks up catastrophically in 20032003

Hulbe

De Angelis & Skvarca, 2003De Angelis & Skvarca, 2003

Glaciers surge into ocean after ice shelves Glaciers surge into ocean after ice shelves collapsecollapse

at the Larsen Ice Shelfat the Larsen Ice Shelf

Steig et al., 2009Steig et al., 2009

...and ...and West Antarctica West Antarctica

is warming faster is warming faster than previously than previously

thoughtthought

Antarctic annual meanAntarctic annual meantemperature anomalies 1957-2006temperature anomalies 1957-2006

Questions:Questions:

Has the WAIS already begun collapsing?Has the WAIS already begun collapsing?

How long will it take?How long will it take?

Has it ever happened before?Has it ever happened before?

...they warrant investigation due to their poorly

constrained contributions to ice sheet stability

under future global warming scenarios

...they warrant investigation due to their poorly

constrained contributions to ice sheet stability

under future global warming scenarios

Fricker, 2008Fricker, 2008

RAGES focuses on grounding zones... RAGES focuses on grounding zones...

Aim is to collect data to Aim is to collect data to help constrain modeling of help constrain modeling of the future behavior of thethe future behavior of theWest Antarctic Ice SheetWest Antarctic Ice Sheet

by Stefan Vogel

So what is important to measure?So what is important to measure?

Amount of melting or freezing on the top surfaceAmount of melting or freezing on the top surfaceAmount of melting or freezing on the bottom surfaceAmount of melting or freezing on the bottom surfaceAmount and distribution of water at the sole of the ice Amount and distribution of water at the sole of the ice sheetsheetAmount and distribution of wet sediment at the sole and Amount and distribution of wet sediment at the sole and the the grounding zone of the ice sheetgrounding zone of the ice sheetFlow velocities of the ice sheet and ice shelfFlow velocities of the ice sheet and ice shelf

Prior ResearchPrior Research

Anandakrishnan et al., 2007Anandakrishnan et al., 2007

Grounding-zone wedge of sediment

accumulating

Grounding-zone wedge of sediment

accumulating

Map & cross-section cartoons show radar line across grounding zone

Map & cross-section cartoons show radar line across grounding zone

Wedge causes ice to thicken, Grounding-line advance past wedge crestStabilizes ice against sea-level rise initially

What are rates of sediment accumulation?What of ocean melt?

Wedge causes ice to thicken, Grounding-line advance past wedge crestStabilizes ice against sea-level rise initially

What are rates of sediment accumulation?What of ocean melt?

Grounding-zone wedgeGrounding-zone wedge

Alley e

t al.

, 2007

Alley e

t al.

, 2007

Anderson, 2007

Dh = -h . δu + a + bDt δxDh = -h . δu + a + bDt δx

Conservation of ice volumeConservation of ice volume

Change of thicknessChange of thickness

Dynamic thinning of ice shelf due to strain rate

Dynamic thinning of ice shelf due to strain rate

Thermodynamic thickening of ice shelf due to surface accumulation

Thermodynamic thickening of ice shelf due to surface accumulation

Thermodynamic thickening or thinning of the ice shelf due to basal freezing or melting in ocean water

Thermodynamic thickening or thinning of the ice shelf due to basal freezing or melting in ocean water

Oceanic melting rates of iceOceanic melting rates of ice

WIS grounding line near an area of low topography where troughs cut across the Ross Sea continental shelf to intercept any warm waters moving up onto

the shelf at depth

WIS grounding line near an area of low topography where troughs cut across the Ross Sea continental shelf to intercept any warm waters moving up onto

the shelf at depth

by S. Vogelby S. Vogel

Diatoms: Microscopic algae that create Diatoms: Microscopic algae that create fossils of opal (glass)fossils of opal (glass)

Fossils beneath the ice sheet tell us of Fossils beneath the ice sheet tell us of times when the WAIS collapsed in the times when the WAIS collapsed in the past, leaving an open seawaypast, leaving an open seaway

Diatoms: Microscopic algae that create Diatoms: Microscopic algae that create fossils of opal (glass)fossils of opal (glass)

Fossils beneath the ice sheet tell us of Fossils beneath the ice sheet tell us of times when the WAIS collapsed in the times when the WAIS collapsed in the past, leaving an open seawaypast, leaving an open seaway

V3590 From Subglacial Lake Vostok

John Priscu

Microbial life beneath Kamb Ice Stream ~107 cells/g sediment Lanoil et al., 2009

Microbial life beneath Kamb Ice Stream ~107 cells/g sediment Lanoil et al., 2009

Priscu et al., 2008

GBASE is integrated with RAGES

Basic research questions: what is the subglacial microbial community structure? what is the metabolic function of the community in situ?

GBASE is integrated with RAGES

Basic research questions: what is the subglacial microbial community structure? what is the metabolic function of the community in situ?

This also helps address an different RAGES goal:Examine significance of subglacial microbial activity and

weathering in supplying nutrients to Ross Ice Shelf cavity and Southern Ocean

This also helps address an different RAGES goal:Examine significance of subglacial microbial activity and

weathering in supplying nutrients to Ross Ice Shelf cavity and Southern Ocean

SourceAntarctica Freshwater Ocean Soil Humans

Gram

s of Carbon

1012

1013

1014

1015

1016

Bacterial carbon in Antarctica compared to other global sources and to cellular carbon in the entire human population

Let’s Pause Two Minutes for Questions?

HOW DO YOU GET HOW DO YOU GET TO THE BOTTOM OF TO THE BOTTOM OF AN ICE SHEET AND AN ICE SHEET AND

ICE SHELF?ICE SHELF?

HOW DO YOU GET HOW DO YOU GET TO THE BOTTOM OF TO THE BOTTOM OF AN ICE SHEET AND AN ICE SHEET AND

ICE SHELF?ICE SHELF?

… “… “drill baby drill”drill baby drill”

- with a lot of hot water and a loooooooong hose- with a lot of hot water and a loooooooong hose

IDPO and S. VogelIDPO and S. Vogel

Mackay GlacierSW Ross Sea

Mackay GlacierSW Ross Sea

Only one other grounding zone

observed

Only one other grounding zone

observed

Grounding line: bedrock, rubble, soft till, hard tillGrounding line: bedrock, rubble, soft till, hard till

Mackay Glacier BenthicCommunity Structure

Mackay Glacier BenthicCommunity Structure

Transect from seaward to landward:

Sites 1 & 2 offshore (G-lb)

Site 3 near grounding line (G)

Sites 4 & 5 “onshore” (G-F)

8 weeks of science in 2013-2014

Transect from seaward to landward:

Sites 1 & 2 offshore (G-lb)

Site 3 near grounding line (G)

Sites 4 & 5 “onshore” (G-F)

8 weeks of science in 2013-2014

G Grounding line (GL)

F limit of Flexure

H Hydrostatic point

Ib Break-in-slope

Im Elevation minimum

after Fricker & Padman, 2006after Fricker & Padman, 2006

RAGES Field PlanRAGES Field Plan

5 proposed sites in grounding zone

Near Subglacial Lake Whillans outlet

Drill through ice shelf into sub-ice-shelf cavity

Drill through ice stream into bed

5 proposed sites in grounding zone

Near Subglacial Lake Whillans outlet

Drill through ice shelf into sub-ice-shelf cavity

Drill through ice stream into bed

BOREHOLE SAMPLING and MEASUREMENTS

5 sites boreholes<800m deep

<0.8-1m diameter

BOREHOLE SAMPLING and MEASUREMENTS

5 sites boreholes<800m deep

<0.8-1m diameter

MEASUREMENTS and SAMPLES:Ice- 5 instruments

Ocean- 15 instruments

Sediment and bed- 17 instruments

MEASUREMENTS and SAMPLES:Ice- 5 instruments

Ocean- 15 instruments

Sediment and bed- 17 instruments

SIR, the Sub-Ice ROVerRemotely Operated Vehicle

a robotically operated submarine

SIR, the Sub-Ice ROVerRemotely Operated Vehicle

a robotically operated submarine

ControsContros COCO22, CH, CH44

Seabird SBE19 Seabird SBE19 Plus-V2Plus-V2

CTD + DOCTD + DO

WET Labs ECO-WET Labs ECO-FLNTU(RT)D,FLNTU(RT)D,

Chlorophyll & Chlorophyll & TurbidityTurbidity

WET Labs C-Star WET Labs C-Star DeepDeep

TransmissometerTransmissometer

Sequoia LISST-Sequoia LISST-DEEPDEEP

Particle-size Particle-size analyzeranalyzer

Envirotech Envirotech nutrient analyzernutrient analyzer

NHNH44, NO, NO33, Si, PO, Si, PO44

EnvirotechEnvirotech Automated water Automated water samplersampler

Deep-sea multi-Deep-sea multi-cam 2065cam 2065

Color cameraColor camera

Teledyne DVS-Teledyne DVS-60006000

Doppler current Doppler current metermeter

Unisense Unisense porewater profilerporewater profiler

pH, redox,T, H, pH, redox,T, H, HH22S, OS, O22, N, N22OO

GIPSIEGeochemical Instrumentation

Package for Sub-Ice Exploration

GIPSIEGeochemical Instrumentation

Package for Sub-Ice Exploration

(with inductive modem,real-time data at

surface)

(with inductive modem,real-time data at

surface)

WHOI ITPWHOI ITP

ITPIce-Tethered Profiler

- RAGES version constructed by McLane Research

- integrated with a Teledyne DVS current meter

ITPIce-Tethered Profiler

- RAGES version constructed by McLane Research

- integrated with a Teledyne DVS current meter

Percussion Sediment Corer - recovers <5m-long cores of stiff sediment - fits through a 20cm borehole - active hammer system driven by a water pump - pumped water between liner-barrel reduces

suction without need of extra-heavy duty winch for pull-out - vibration mode for aiding penetration or pull-out

Percussion Sediment Corer - recovers <5m-long cores of stiff sediment - fits through a 20cm borehole - active hammer system driven by a water pump - pumped water between liner-barrel reduces

suction without need of extra-heavy duty winch for pull-out - vibration mode for aiding penetration or pull-out

Additional Education Resources Additional Education Resources about Antarctica and the RAGES about Antarctica and the RAGES

ProjectProject

WISSARD: WISSARD: http://wissard.orghttp://wissard.org

ANDRILL-Antarctic Geological Drilling: ANDRILL-Antarctic Geological Drilling:

http://andrill.orghttp://andrill.org

Climate Change Resources: Climate Change Resources:

http://andrill.org/flexhibithttp://andrill.org/flexhibit

NSF “Antarctica” Book: NSF “Antarctica” Book:

http://andrill.org/publicationshttp://andrill.org/publications

RAGES Video:RAGES Video:

http://www.ag.montana.edu/rages/http://www.ag.montana.edu/rages/

ROVintrovideo.mov ROVintrovideo.mov

RAGESRAGES

http://wissardwissard.orghttp://wissardwissard.org

Thank you to the sponsor of tonight's Web Seminar:

http://learningcenter.nsta.org

http://www.elluminate.com

National Science Teachers AssociationDr. Francis Q. Eberle, Executive Director

Zipporah Miller, Associate Executive Director Conferences and Programs

Al Byers, Assistant Executive Director e-Learning

LIVE INTERACTIVE LEARNING @ YOUR DESKTOP

NSTA Web SeminarsPaul Tingler, Director

Jeff Layman, Technical Coordinator