HR: 0800h
AN: U41C-0621    [Abstracts]
TI: Composition of Upper Arctic Ocean Water Masses North of Ellesmere Island
AU: * Smethie, W M
EM: bsmeth@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964, United States
AU: Schlosser, P
AF: Department of Earth and Environmental Sciences and Department of Environmental Engineering, Columbia University, 2960 Broadway, New York, NY 10027, United States
AU: Newton, B
AF: Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964, United States
AU: Steele, M
AF: Applied Physics Lab, University of Washington, Boat Street, Seattle, WA 98105,
AU: Morison, J
AF: Applied Physics Lab, University of Washington, Boat Street, Seattle, WA 98105,
AB: As part of the Switchyard project CTD measurements and water samples have been collected beneath the sea ice North of Ellesmere Island in the spring between 2005 and 2007. The water samples have been analyzed for oxygen, nutrients, anthropogenic tracers, and oxygen-18. The core water masses have distinct signals in these various constituents and the data have been used to estimate the water mass composition and fresh water sources in the upper few hundred meters of the water column. The seawater component of the upper 100 m is primarily derived from the Pacific Ocean, but also contains about 10% meteoric water. The halocline extends from about 80 m to about 200 m and across this layer the fraction of Pacific water decreases from roughly 90% to ca. 10%; the opposite trend is observed in Atlantic water distribution. The fraction of meteoric water decreases from about 10% at the base of the mixed layer to zero at 200 m. The sea ice melt water fraction is negative in the upper 150 m indicating this is a region of sea ice formation and export.
DE: 4207 Arctic and Antarctic oceanography (9310, 9315)
DE: 4283 Water masses
DE: 4536 Hydrography and tracers
SC: Union [U]
MN: 2007 Fall Meeting