Freshwater fluxes through the western Fram Strait

Abstract

Two hydrographic and δ18O transects across Fram Strait (Aug-Sept 1997, 1998) are used to examine freshwater contributions to the East Greenland Current (EGC). The EGC featured up to Ο˜ 16% meteoric water in both years, but was made comparatively more saline through the formation of up to Ο˜11 m of sea ice. We derive meteoric water fluxes of Ο˜3680 km3yr-1 in Aug-Sept 1997, and Ο˜2000 km3yr-1 in Aug-Sept 1998. The 1997 and 1998 data show a long-term me˜m sea ice flux through Fram Strait around half the long-term mean meteoric water flux. A 1991 δ18O section [Bauch et al., 1995] yielded a very similar ratio. Our 1998 section reveals fresh, 1ow-6180 water on the East Greenland shelf whose comparatively large volume constitutes a potentially significant contribution to the total freshwater flux through Fram Strait. Such fluxes are important to the regional and global thermohaline circulation; we suggest that efforts towards monitoring both the EGC and East Greenland shelf waters are thus required.