TY - JOUR

T1 - Eddies in the North Greenland Sea and Fram Strait From Satellite Altimetry, SAR and High-Resolution Model Data

AU - Bashmachnikov, Igor L.

AU - Kozlov, Igor E.

AU - Petrenko, Larisa A.

AU - Glok, Natalia I.

AU - Wekerle, Claudia

PY - 2020/7/1

Y1 - 2020/7/1

N2 - In this study, we investigate eddy dynamics in the northern Greenland Sea and the Fram Strait using AVISO altimetry, spaceborne synthetic aperture radar (SAR), and Finite Element Sea ice-Ocean Model (FESOM) high-resolution numerical model data. In the region, eddies are thought to play an important role in the redistribution of the warmer and saltier Atlantic Water between the Arctic Ocean and the areas of deep convection in the central Greenland Sea. We found that eddies detected in AVISO and in SAR form two complementary data sets of large mesoscale eddies (with typical radii of 30–50 km) and of small mesoscale/submesoscale eddies (with typical radii of 1–5 km and not exceeding 30 km), respectively. For large mesoscale eddies, the number of cyclones and anticyclones is approximately the same, while for submesoscale eddies, cyclones are strongly dominating. The limitations and possible biases in each of the data sets are discussed and cross-validated against FESOM results. It is noted that the most energetic eddies are concentrated along the major currents and in the northern part of the region. Eddy translations follow the mean currents in their overall cyclonic circulation around the northern Greenland Sea. A convergence of the eddies toward the Nordbukta area is detected. On seasonal time scale, a higher number of more intense mesoscale eddies is observed during winter, associated with a quasi-simultaneous intensification of the mean currents. Model results also show an increase in the number of small eddies in spring-early summer attributed to the decay of large eddies, while in late autumn, the opposite tendency suggests eddy merger.

AB - In this study, we investigate eddy dynamics in the northern Greenland Sea and the Fram Strait using AVISO altimetry, spaceborne synthetic aperture radar (SAR), and Finite Element Sea ice-Ocean Model (FESOM) high-resolution numerical model data. In the region, eddies are thought to play an important role in the redistribution of the warmer and saltier Atlantic Water between the Arctic Ocean and the areas of deep convection in the central Greenland Sea. We found that eddies detected in AVISO and in SAR form two complementary data sets of large mesoscale eddies (with typical radii of 30–50 km) and of small mesoscale/submesoscale eddies (with typical radii of 1–5 km and not exceeding 30 km), respectively. For large mesoscale eddies, the number of cyclones and anticyclones is approximately the same, while for submesoscale eddies, cyclones are strongly dominating. The limitations and possible biases in each of the data sets are discussed and cross-validated against FESOM results. It is noted that the most energetic eddies are concentrated along the major currents and in the northern part of the region. Eddy translations follow the mean currents in their overall cyclonic circulation around the northern Greenland Sea. A convergence of the eddies toward the Nordbukta area is detected. On seasonal time scale, a higher number of more intense mesoscale eddies is observed during winter, associated with a quasi-simultaneous intensification of the mean currents. Model results also show an increase in the number of small eddies in spring-early summer attributed to the decay of large eddies, while in late autumn, the opposite tendency suggests eddy merger.

KW - eddies

KW - FESOM model

KW - Fram Strait

KW - SAR

KW - satellite altimetry

KW - the North Greenland Sea

KW - MARGINAL ICE-ZONE

KW - BAROCLINIC INSTABILITY

KW - NORDIC SEAS

KW - SURFACE CIRCULATION

KW - WEST SPITSBERGEN CURRENT

KW - ATLANTIC WATER

KW - OCEAN CIRCULATION

KW - LOFOTEN BASIN

KW - MEDITERRANEAN WATER EDDIES

KW - MESOSCALE EDDY FIELD

UR - http://www.scopus.com/inward/record.url?scp=85088589299&partnerID=8YFLogxK

U2 - 10.1029/2019JC015832

DO - 10.1029/2019JC015832

M3 - Article

AN - SCOPUS:85088589299

VL - 125

JO - Journal of Geophysical Research: Biogeosciences

JF - Journal of Geophysical Research: Biogeosciences

SN - 0148-0227

IS - 7

M1 - e2019JC015832

ER -