1. Summit science summary
Key facility in Arctic observatory network – increasing use, but also demand for pollution-free sampling environment
Unique location on ice sheet provides year-round access to remote, high-elevation Arctic atmosphere & ice sheet
Only northern hemisphere location for polar ice sheet intercomparisons with Antarctic
Growing science use by multiple geophysical disciplines & aging infrastructure drive need for new investments
Vision:
Model international research facility – site of leading-edge polar & global multidisciplinary science
Long-term geophysical measurements
Intensive campaigns: atmospheric & multiple other disciplines
Test bed for new sensors & technology
Clean scientific observatory, with sustainable infrastructure, renewable energy, minimum pollution, year-round operation for diverse, high-impact science

2. Nearly 20 years of science at GEOSummit
: main focus was GISP2 ice core
Studies of air-snow exchange for ice-core interpretation & studies of the remote arctic troposphere every year since 1989, involving scientists from dozens of institutions
Year-round operations since 2000 & key component of arctic & global atmospheric observation system since 2003 (e.g. GAW, AON, IASOA, NOAA ESRL)
Growing demands for scientific use by diverse geophysical disciplines, with some facilities dating back to GISP2, make investments in new infrastructure a high priority.

3. Ice coring at Summit Peak of the Greenland ice sheet.
72ºN, 38ºW 3,200 masl
Sampling for trace metals in snow
Peak of the Greenland ice sheet.
No significant melting (yet!)
GISP2 provided unprecedented high-resolution record of the past 110k yr of Earth’s climate & atmospheric chemistry.
Studies of air-snow chemical exchange show both linear & non-linear “transfer functions”
Dome protecting GISP2 ice core drill,

4. Atmospheric chemistry at Summit
Site for many productive atmospheric measurement campaigns & experiments
Production of NOx in sunlit snow, discovered at Summit in 1998, helped launch field of snow photochemistry.
Degassing of hydrogen peroxide & formaldehyde from snow create highly oxidizing environment near snow surface.
NOAA scientists measure detailed profiles of stratospheric ozone
Site for baseline measurements of globally important gases, aerosols in troposphere & stratosphere

5. Summit in IASOA & AON
Illustrative of key role in multiple Arctic & global observing networks
Remote ice-sheet location
Only high elevation station
Regularly samples polar dome air
Represents northern hemisphe, free of regional influence