Major NASA activities in the Arctic

Arctic sea ice extent and thickness is declining

The average thickness of the Arctic’s sea ice declined by 30% from 2003 to 2008.

The last four years have seen the lowest four minimum extents ever recorded for Arctic sea ice.

Feb-Mar 2003

Feb-Mar 2008

FARRELL ET AL., JOURNAL OF GEOPHYSICAL RESEARCH, 2009

NASA’s researchers and satellite and aircraft observation tools are global leaders of this work. This work is critical to understanding polar feedbacks into global climate, as well as meeting US planning needs in the Arctic; from understanding environmental change to security and economic decisions

Shifts in sea ice persistence and Chl-a concentration from 2003-2009 Courtesy Frey&Grebmeier

Based on SSM/I Sea Ice Concentrations and the GlobColour satellite time series,

Take home points:

• Satellites map changes in base of food chain

• Major contribution to Distributed Biological Observatory

• Critical to understanding future resources and livelihoods for the Alaskan economy, as well

as feedbacks for global carbon budget

NASA’s ICESCAPE cruise to improve understanding of Arctic

ocean ecosystems made the discovery of phytoplankton concentration amongst the highest ever observed anywhere on earth. Even more astounding it was under thick sea ice with limited light penetration.

Unique approaches to understanding the elusive Arctic Mapping ocean currents from satellite:

Changing Arctic Ocean Freshwater Pathways

Morison, J., R. Kwok, C. Peralta-Ferriz, M. Alkire, I. Rigor, R. Andersen, and M. Steele. Nature 481, 66-70 (2012) doi:10.1038/nature10705

• Sea surface height from ICESat and ocean bottom pressure trends from GRACE show Canada Basin freshwater content increase balanced by decrease in the Eurasian Basin (2005-2008).

• Chemistry observations show the Canada Basin freshwater increase due to increased presence of Eurasian runoff.

• Satellite observations show changes due to counterclockwise shift in the ocean pathway of Eurasian runoff forced by strengthening of the west-to-east Arctic Oscillation (AO).

• This high-AO process likely characterizes the dramatic Arctic Ocean changes since the early 1990s. Climate models must capture the Arctic expression of the AO accurately if they are to project the fate of Arctic freshwater and its effect on climate.

Right-Top: ICESat measured sea surface height trends

(contours) which determine near surface ocean pressure gradients

that drive surface currents (arrows).

Bottom: ocean bottom pressure trend minus ICESat sea surface

height trend yields countours of steric pressure trends and

freshwater content trend.

1

2

3

4

5

6

7

8

+3 Gt/yr +15

Gt/yr

-41 Gt/yr

-69 Gt/yr

-9

Gt/y

r

-3

Gt/yr

-14

Gt/yr

-33

Gt/yr

-151 Gt/yr

total

2003 to 2007

ELA 2000 m

Ice sheet and glacier mass change NASA scientists use a range of satellites, aircraft missions, and other approaches with an overall goal of improving estimates of current and future sea level rise

Images courtesy

Larsen, Vaughan,

Zwally, Joughin

and Luthcke

Operation IceBridge

IceBridge is also making other key measurements to improve predictive models for ice-sheet evolution.

Bridging the gap between the ICESat and ICESat-2 missions, NASA is deploying aircraft to monitor the Greenland and Antarctic ice sheets, as well as sea ice in both regions.

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IceBridge Trajectory Maps

Comprehensive Imaging of Ice Sheets and Ice

Shelves from Top to Bottom

with IceBridge Instrument Suite

Pine Island Glacier, Antarctica, 2009

Images illustrate the deep trough upstream of the floating Pine Island Glacier tongue. Also evident are several tributary glaciers that traverse mountainous terrain on the eastern flank of the glacier. Results show the generally excellent correspondence between the ASAID grounding line and subsurface topography, though in some places OIB data can be used to refine grounding line placement. Qualitatively, surface velocity directions are consistent with subglacial topography suggesting that flow divergence with depth may be small.

Image from Jezek and Dhanasekaran (Dhanasekaran M.S Thesis, 2011, The Ohio State University)

bathymetry from gravity inversion (Studinger)

bottom of ice sheet from radar (CReSIS)

ice surface from ATM and Radarsat (ATM and Jezek)

New Polar activities in planning

Ice Cloud and land Elevation Satellite-2 (ICESat-2)

Ice sheet mass balance from elevation change

Sea ice thickness from freeboard

Large-scale biomass from vegetation height

3 sets of 2 beams • density of coverage • simultaneous

measurement slope and elevation

Micropulse lidar • Low energy • High rep-rate • 70 cm along-track sampling

Waleed Abdalati, ESOC/CIRES, Univ. of Colorado, IPCC Sea Level Meeting, Kuala Lumpur, Malaysia, June 21-24, 2010

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Remote sensing data can offer regional context, help address uncertainties, and inform and assess models

Change in Arctic & Boreal Region (ABR) unfolding faster than anywhere else on Earth

NASA’s Carbon Cycle & Ecosystems Program is planning

Arctic-Boreal Vulnerability Experiment (ABoVE), a major field, aircraft, and space-based remote sensing campaign

NASA’s Arctic datasets

NSIDC: An overview 14

National Snow and Ice Data Center: A NASA Distributed Active Archive Center (DAAC) for the cryosphere

• Hosts >100 Tb of data, and distributes more than double that each year

• Includes Earth System Data Records: integrated, multi-year to decadal datasets that improve usability for other disciplines, e.g. freeze-thaw, temp, sea ice motion

• AMSR-E (Aqua)

• AMSR (ADEOS II)

• SMMR (Nimbus 7)

• SSM/I, SSMIS (DMSP

series)

VIS/IR Moderate

Resolution

• MODIS (Terra/Aqua)

snow and ice products

• AVHRR polar data

(NOAA series)

Satellite & Airborne

Altimetry

• ICESat I/GLAS altimetry

and atmospheric lidar data

• Digital Elevation Models

(DEMs)

• IceBridge

Passive Microwave

AMSR-E 12.5 km Sea Ice Concentration MODIS Monthly Global Snow Cover IceBridge ATM Qfit Data on Landsat Image

Earth System Data Records: integrating and improving usability for other disciplines

NASA has made major awards to synthesize satellite records critical to polar work, including:

Courtesy U. Montana/JPL

• Greenland ice sheet velocities (InSAR) • Antarctic ice sheet velocities (InSAR) • Arctic sea ice kinematics

• Global snow cover (30-yr record) • Daily freeze-thaw maps (below)

Products at NSIDC

MEaSUREs

ESDR (Earth Science Data Record) of Small-Scale Kinematics of the Arctic and Southern Oceans: A new data set based on Envisat

Science uses of ice motion products • Assess linear kinematic features (fracture

patterns) in new models of anisotropic sea mechanics

• Subdaily ice motion for understanding impact of small-scale and short-timescale ice deformation on ice production

• Study of oceanic heat flux due at shear lines in the ice cover (i.e., doming of the pycnocline)

• Ice area export at the Nares Strait and Fram Strait

• Validation of lower resolution ice drift in lower resolution sensors

• Users: • (US) Naval Postgraduate School, U New

Mexico U Washingto, JPL • (Europe) Nansen Remote Sensing Center, U of

Reading, U of Grenoble, Alfred Wegener Institute, Norwegian Polar Insitute, ESA CCI ECV ice drift, U Hamburg

• (Australia) U of Tasmania

Ron Kwok, Jet Propulsion Laboratory Composite deformation fields of the Weddell Sea ice cover from 1-day motion Envisat

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MEaSUREs

ESDR (Earth Science Data Record) of Small-Scale Kinematics of the Arctic and Southern Oceans: A new data set based on Envisat

Description and Objectives • Process the Envisat data stream (2007-2012) to

construct ESDRs of small-scale ice motion of the Arctic and Southern Oceans;

• Develop products that take advantage of the temporal (subdaily to 1-day) and spatial sampling scheme of the Envisat mission;

• Produce mosaics of the Envisat images of the Arctic Ocean;

• Create a multi-year time series of Fram Strait and Nares Strait sea ice export;

• Address the use of Sentinel-1 data sets for producing ESDR of the Arctic and Antarctic ice cover.

• Note: Sentinel-1 data are needed to continue record of changes in small-scale deformation

Ron Kwok, Jet Propulsion Laboratory Composite deformation fields of the Arctic Ocean ice cover

from 1-day motion Envisat

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2000/1

2005/6

2006/7

2007/8

Greenland Ice Mapping Project

2008/9

Composite

2009/10

2010/11

2011/12

TSX provides more limited coverage but captures most fast-

moving outlets at high-resolution and more frequent

sampling

Both targeted high res (TSX-like) coverage and lower res

(RADARSAT-like) coverage are crucial for understanding

flow variability in Greenland.

Velocity mapping of the Great Ice Sheets: Antarctica NASA MEaSUREs-1 (2006-2012). PI: E. Rignot, Proj. Scientists J. Mouginot and B. Scheuchl

Objective Develop and distribute a new set of Earth System Data Records (ESDR) of ice velocity in Antarctica. Goal Assemble and distribute the first true continent-wide ice velocity map of Antarctica. This project would not have been possible without the support from STG

Approach • Build on existing extensive team

expertise and scale up for continent-wide processing.

• Work with space agencies (i.e. STG) to gain international support and access to IPY large scale SAR acquisition campaigns.

Achievements Multiple continent products completed:

• First ever continent-wide velocity map • Interferometric grounding line map • Time series of velocity in key areas

Key publications in high profile journals.

Significant international media attention.

Widespread use of the ESDRs in the science community.

Ice velocity and grounding line products available at NSIDC http://nsidc.org/data/measures/data_summaries.html

Ice Velocity Mapping of the Antarctic Ice Sheet NASA MEaSUREs-2 (2013-2018). PI: Eric Rignot, Proj. Scientists J. Mouginot and B. Scheuchl

Objective Produce and distribute Earth System Data Records (ESDR) of ice velocity in Antarctica.

Goals

Time series of ice velocity from 1996, 2000, 2006-2013, to present. PSTG support is critical for project success

Approach • Build time series of selected regions and

ice sheet wide mapping on select years. • Historic data sets (RAMP 2000, ERS-1

1996). • Work with space agencies to plan and

implement future data acquisitions. • Advise NISAR project team on ice sheet

requirements (separate contract).

Achievements: Amundsen Sea.

Rignot, E., J. Mouginot, M. Morlighem, H. Seroussi, and B. Scheuchl (2014), Widespread, rapid grounding line retreat of Pine Island, Thwaites, Smith, and Kohler glaciers, West Antarctica, from 1992 to 2011, Geophys. Res. Lett., 41, 3502–3509, doi:10.1002/2014GL060140. Mouginot, J., E. Rignot, and B. Scheuchl (2014), Sustained increase in ice discharge from the Amundsen Sea Embayment, West Antarctica, from 1973 to 2013, Geophys. Res. Lett., 41, 1576–1584, doi:10.1002/2013GL059069.

Widespread international media coverage of the findings. US: reached two out of three national TV news broadcasts and the top tier newspapers in the country. Time series of Amundsen sea since 1975 released at NSIDC.

1996

100 km

A1

A2

B1

B2

C1

C2

D1

D2E1

E2F1

F2G1

G2

(a)

2008 - 1996

100 km

(b)

Pine Island Gl.

Thwaites Gl.

Haynes Gl.

Pope Gl.

Smith Gl.

Kohler Gl.

Eastern IS

Thwaites Ice Tongue

Crosson

Dotson

Ice Velocity (km/yr)

<0.0015 0.01 0.1 1 >3 <-1.5 -0.1 -0.01 >1.50.10.01

Vel. difference (km/yr)

Evolution of ice velocity in the Amundsen Sea Embayment area

Ice Velocity Mapping of the Antarctic Ice Sheet NASA MEaSUREs-2 (2013-2018). PI: Eric Rignot, Proj. Scientists J. Mouginot and B. Scheuchl

What we have, thanks to PSTG: • Access to RAMP-1, ERS-1 archive from 1995-

1996, all ALOS PALSAR 2006-2010. • Access to Sentinel-1 starting January 1, 2015. • Antarctic campaigns of RADARSAT-2 in 2013. • Limited access to TanDEM-X and TerraSAR-X. • Access to Landsat 8 for coastal mapping (not

planned initially).

What we need, with the help from PSTG: • More systematic acquisitions from Sentinel1a/1b

over Antarctica using a fixed set of tracks in order to build time series at the continental scale.

• Access to COSMO Skymed for short time repeat and grounding line mapping in Amundsen Sea and other key sectors.

• Access to ALOS-2 PALSAR planned data acquisitions (acquisitions planned but data access is limited).

• Larger access to TerraSAR-X archive.

1996

100 km

A1

A2

B1

B2

C1

C2

D1

D2E1

E2F1

F2G1

G2

(a)

2008 - 1996

100 km

(b)

Pine Island Gl.

Thwaites Gl.

Haynes Gl.

Pope Gl.

Smith Gl.

Kohler Gl.

Eastern IS

Thwaites Ice Tongue

Crosson

Dotson

Ice Velocity (km/yr)

<0.0015 0.01 0.1 1 >3 <-1.5 -0.1 -0.01 >1.50.10.01

Vel. difference (km/yr)

Evolution of ice velocity in the Amundsen Sea Embayment area

COSMO Skymed grounding line of Petermann Gl. In 2013.

Agency Steps Towards responding to User Needs

This site allows DBO researchers quick access to key remote sensing datasets for marine observations:

Wind speed

Ocean color (Chlorophyll)

Sea surface temperature

Sea ice concentration

Cloud cover

Surface pressure

NASA’s Distributed Biological Observatory (DBO) site Bridging the gap to help IARPC agencies and scientists lacking remote sensing experience through websites, viewers, and integrated datasets to help them put Arctic change in context.

• Temperature

• Freeze thaw

• Vegetation change (NDVI)

• Water vapor

• Snow cover

• Sea ice cover

• Others in development

Satellite records of the critical Arctic variables—some spanning three decades. Allows users to see change across entire Arctic down to pixel level of the data.

Satellite Observations of Arctic Change