1. Operation IceBridge: using instrumented aircraft to bridge the observational gap between ICESat and ICESat-2

2. New Suborbital Mission: Operation IceBridge

4. successful collaboration of several NASA centers run out of Goddard University Partners: University of Kansas (CReSIS) Columbia University (LDEO)

5. IceBridge exploits airborne platforms when making altimetry measurements to make other critical measurements to understanding change in polar ice sheets: most comprehensive and sophisticated suite of instruments ever flown in polar regions Instrument Operator Measurement Type ATM NASA – WFF ice surface (1,500 ft AGL) laser altimeters LVIS NASA – GSFC ice surface (35,000 ft AGL) DMS NASA – ARC digital photography MCoRDS KU CReSIS bedrock elevation radars for snow and ice thickness snow radar KU CReSIS snow thickness Ku-band radar KU CReSIS ice surface elevation accumulation radar KU CReSIS near-surface layers gravimeter SGL/ LDEO water depth, geoid onboard data NSERC aux. data: temperature, etc.

8. 2012 – 2015: start deploying Global Hawk over Antarctica in addition to NASA campaigns: smaller, university-led campaigns in Alaska and East Antarctica with DHC-3 and DC-3s two campaigns per year to monitor temporal and spatial changes Arctic (Mar-Apr) Antarctica (Oct-Nov) P-3B: Greenland and Arctic Ocean DC-8: Antarctic Peninsula and West Antarctica

9. Total: 143 days of deployment 69 science missions 581 flight hours 350,000 km (8.6 times around the Earth) Greenland 2010 Antarctica 2009 Greenland 2009 Greenland 2010 Antarctica 2010 Jan 2009 Jan 2011 Jan 2010 Jul 2009 Jul 2010 P-3 DC-8 P-3 DC-8 planned DC-8

10. Antarctica 2009 Greenland/Arctic Ocean 2010 flight lines follow ICESat tracks and provide detailed mapping of critical areas

14. DC-8 over flight April 14, 2010 IceBridge DC-8 flying above GPS sled both measuring surface elevation Scientist measuring accumulation stacks along ICESat Track 412

16. IceBridge “pole hole” flight: 7 years of ICESat observations differenced with LVIS: ~500,000 data points South Pole 86°S Credit : LVIS Team

17. This data calibrates ICESat data over the ice sheet, improving and extending the ICESat time series Uncertainties in ICESat determined dh/dt on the order of one-third to several times the GIS and AIS mass balance signal LVIS pole hole flight ICESat (Arctic Ocean) ICESat range bias determined from Credit: Michelle Hofton and Scott Luthcke

19. ice surface velocity red = fast – blue = slow Pine Island Glacier is considered to have the greatest propensity to cause rapid sea level rise due to the massive volumes of ice that could be released rapid bottom melting near grounding line of up to 80 m/yr, potentially unstable situation sub-ice cavity geometry is needed to modeling of ice shelf decay, considered the greatest unknown in modeling of future sea level rise.

21. ICESat tracks ATM flight tracks 2009 ATM – 2003 ICESat 2009 ATM – 2003 ATM Ice surface velocity: red = fast – blue = slow IceBridge ATM laser altimeter data 100 km

22. Right: the deep channel (blue) mapped by IceBridge is a new discovery. The channel lies about 1 km below sea level, and provides a path for the above-freezing sea water to reach the glacier front. Data is critical for ocean/ice sheet models to predict dynamic response of Pine Island Glacier to warming ocean waters. water depth beneath floating glacier: blue = deep – red = shallow