TY - JOUR
KW - 0752 Cryosphere: Polynas
KW - 1041 Geochemistry: Stable isotope geochemistry
KW - 1621 Global Change: Cryospheric change
KW - 4872 Oceanography: Biological and Chemical: Symbiosis
KW - Arctic
KW - East Greenland Current
KW - oxygen isotopes
KW - sea ice
AU - K. Cox
AU - J. Stanford
AU - A. McVicar
AU - E.J. Rohling
AU - K. Heywood
AU - S. Bacon
AU - M. Bolshaw
AU - P. Dodd
AU - S. De la Rosa
AU - D. Wilkinson
AB - Observations since the 1950s suggest that the Arctic climate system is changing in response to rising global air temperatures. These changes include an intensified hydrological cycle, Arctic sea ice decline, and increasing Greenland glacial melt. Here we use new δ<sup>18</sup>O data from the East Greenland Current system at Cape Farewell and Denmark Strait to determine the relative proportions of the freshwater components within the East Greenland Current and East Greenland Coastal Current. Through the comparison of these new data with historical studies, we gain insight into the changing Arctic freshwater balance. We detect three key shifts in the net freshwater component δ<sup>18</sup>O values, these are (1) a shift to lighter values in the late 1990s that possibly indicates an increased Greenland glacial melt or a reduced sea ice melt admixture and (2) a short-term shift to a \~10\textperthousand heavier value in 2005 followed by (3) a shift back to the historic average value in 2008. The latter fluctuation reflects a short-term dramatic rise and fall of sea ice meltwater addition into the East Greenland Current system. We infer that this anomalously large inclusion of sea ice meltwater resulted from a short-term peak in Arctic sea ice export via Fram Strait. Our findings, therefore, suggest that the freshwater carried in the East Greenland Current system is susceptible to short-term, high-amplitude changes in the upstream freshwater balance, which may have important ramifications for the global thermohaline circulation through the suppression of deep water formation in the North Atlantic.
BT - Journal of Geophysical Research
M1 - C12
N2 - Observations since the 1950s suggest that the Arctic climate system is changing in response to rising global air temperatures. These changes include an intensified hydrological cycle, Arctic sea ice decline, and increasing Greenland glacial melt. Here we use new δ<sup>18</sup>O data from the East Greenland Current system at Cape Farewell and Denmark Strait to determine the relative proportions of the freshwater components within the East Greenland Current and East Greenland Coastal Current. Through the comparison of these new data with historical studies, we gain insight into the changing Arctic freshwater balance. We detect three key shifts in the net freshwater component δ<sup>18</sup>O values, these are (1) a shift to lighter values in the late 1990s that possibly indicates an increased Greenland glacial melt or a reduced sea ice melt admixture and (2) a short-term shift to a \~10\textperthousand heavier value in 2005 followed by (3) a shift back to the historic average value in 2008. The latter fluctuation reflects a short-term dramatic rise and fall of sea ice meltwater addition into the East Greenland Current system. We infer that this anomalously large inclusion of sea ice meltwater resulted from a short-term peak in Arctic sea ice export via Fram Strait. Our findings, therefore, suggest that the freshwater carried in the East Greenland Current system is susceptible to short-term, high-amplitude changes in the upstream freshwater balance, which may have important ramifications for the global thermohaline circulation through the suppression of deep water formation in the North Atlantic.
PB - AGU
PY - 2010
SN - 0148-0227
EP - C12063
T2 - Journal of Geophysical Research
TI - Interannual variability of Arctic sea ice export into the East Greenland Current
UR - http://dx.doi.org/10.1029/2010JC006227
VL - 115
ER -