Mattia Almansi – Department of Earth and Planetary Sciences – The Johns Hopkins University – Baltimore – MD – USA
The subpolar North Atlantic is dynamically relevant to the global climate system because dense water masses affecting the thermohaline circulation are formed and transformed there. About half of the dense water that sinks in the North Atlantic is supplied by the Denmark Strait overflow (DSO), making the strait a critical gateway between the Arctic and the subpolar North Atlantic. One of the largest contributors to the DSO is the East Greenland Current (EGC), which flows southward along the eastern coast of Greenland.
I will present results from our high-resolution (∼2 km) numerical circulation model covering the east Greenland shelf, and the Iceland and Irminger Seas. Such high resolution allows us to investigate in detail the causal relationship between the two dominant mesoscale features in the strait (known as “boluses” and “pulses”) and the overflow cyclones observed downstream. We also interpret the sparse observations available upstream of Denmark Strait using our model. In particular, we found that eddy activity and separation of the EGC play key roles in setting the hydrographic properties of the water masses that enter the North Atlantic.