Operation IceBridge

Operation IceBridge
Name	Operation IceBridge
Start	2009
End	2019
Sponsor	National Aeronautics and Space Administration
Region	Arctic, Antarctic
Type	airborne geophysical survey

Operation IceBridge was a decade-long airborne geophysical campaign led by National Aeronautics and Space Administration to monitor polar ice and bridge data gaps between satellite missions. The project combined aircraft platforms, remote sensing instruments, and field teams to measure sea ice, ice shelves, glaciers, and ice sheets across the Arctic and Antarctic. IceBridge produced time series that complemented observations from missions such as ICESat and ICESat-2, informing studies by institutions including NASA Goddard Space Flight Center, University of Colorado Boulder, and British Antarctic Survey.

Background and Objectives

IceBridge was initiated after the loss of the first ICESat satellite laser altimeter and before the launch of ICESat-2, aiming to maintain continuity in altimetric, radar, and photographic records. Goals included quantifying mass balance for the Greenland Ice Sheet, Antarctic Ice Sheet, and peripheral glaciers like those in the Alaska Range and Patagonia Icefields, characterizing changes at grounding lines tied to Totten Glacier and Thwaites Glacier, and improving process understanding related to calving at ice fronts such as Jakobshavn Glacier and Pine Island Glacier. Scientific partners extended to National Science Foundation, Centre National de la Recherche Scientifique, Geological Survey of Denmark and Greenland, and university consortia.

Mission History and Timeline

Operations began in 2009 with seasonal field campaigns timed to polar climates and satellite schedules. Early flights in 2009–2010 focused on supporting ICESat data calibration while expanding regional coverage. As ICESat-2 development progressed, IceBridge adapted flight lines to provide cross-comparisons and validation in 2016–2019. Major milestones included first systematic airborne lidar mapping over the Greenland Ice Sheet in 2009, extended Antarctic campaigns from McMurdo Station and Palmer Station basing, and the final coordinated surveys that overlapped with CryoSat-2 tracks and Operation IceBridge follow-on programs.

Aircraft, Instruments, and Methods

IceBridge deployed multiple aircraft including the Douglas DC-8, P-3 Orion, Basler BT-67, and the De Havilland Twin Otter for regional work. Instruments integrated on these platforms included airborne laser altimeters derived from GLAS heritage, multifrequency radar sounders for ice-penetrating profiling, airborne gravimeters, and digital photogrammetric cameras linked to inertial navigation systems like GPS and Star Tracker assemblies. Scientific methods combined repeat-track altimetry, ice-penetrating radar stratigraphy, snow-depth retrievals, and stereo-imagery processing to derive surface elevation, bed topography, and mass change estimates comparable to data products from ICESat, CryoSat-2, and GRACE.

Major Campaigns and Areas Surveyed

Campaigns targeted the Greenland Ice Sheet outlet glaciers including Helheim Glacier, Kangerlussuaq Glacier, and Jakobshavn Isbræ; Antarctic focus included the Antarctic Peninsula, West Antarctic Ice Sheet regions such as Thwaites Glacier and Pine Island Glacier, and the East Antarctic Ice Sheet margins near Totten Glacier. Regional surveys covered the Canadian Arctic Archipelago, Svalbard, Iceland, Alaska, and coastal zones like Ross Ice Shelf and Amundsen Sea embayments. Seasonal missions also supported field projects near McMurdo Station logistics hubs and collaborated with campaigns from Polarstern and RV Nathaniel B. Palmer.

Key Findings and Scientific Impact

IceBridge yielded high-resolution observations that documented thinning and dynamic acceleration at major outlets, refined mass-balance estimates for Greenland, and revealed basal topography beneath formerly uncharted ice streams influencing grounding line retreat at Pine Island Glacier and Thwaites Glacier. Comparisons with ICESat and ICESat-2 demonstrated measurement continuity and improved uncertainty quantification for polar elevation change, while synergies with GRACE and CryoSat-2 enhanced mass-loss attribution between surface processes and basal melting. Results influenced assessments by Intergovernmental Panel on Climate Change authors, informed numerical models used by groups at NASA Jet Propulsion Laboratory and University of Oslo, and supported coastal impact studies relevant to United Nations sea-level projections.

Data Management and Accessibility

Data from IceBridge were archived and distributed through repositories managed by NASA, including the National Snow and Ice Data Center and NASA Distributed Active Archive Center. Products included laser altimetry profiles, radar echograms, digital elevation models, and calibrated imagery with metadata linking to flight logs and instrument calibration records. The open-access policy facilitated reuse by researchers at Massachusetts Institute of Technology, University of Washington, Scripps Institution of Oceanography, and international partners, enabling cross-disciplinary studies in cryospheric science, oceanography, and climate assessment.

Category:Cryospheric research programs