Abstract:
Landfast ice is nearly immobile sea ice attached to the coast.Landfast ice inhibits atmo- sphere-ocean fluxes of heat moisture, and momentumleads to offshore flaw polynyas. and stores fresh river water in wintertime.Despite these important roles in coastal envi- ronments. landfast ice is not well simulated in current sea ice models. because landfastice dynamics differ from the pack ice in the interior Arctic and require explicit parameteriza- tion.The dynamical mechanisms for landfast ice formation are linked to the local geogra phy. Grounded ice ridges act as anchor points in shallow water.Coastlines and offshore island chains may also be pinning points between which arches of landfast ice can form in deep water. The grounding mechanism for landfast ice in shallow marginal seas has been successfully parameterized using bathymetry information but this grounding scheme fails in deep regions.We describe a new landfast ice parameterization that uses lateral drag as a function of sea ice thicknessdrift velocityand local coastline length.The simulated landfast ice in a 36 km pan-Arctic sea ice-ocean simulation is compared to observations from satellite data and the effect ofthe new lateral drag parameterization is evaluated. The combination of the established grounding scheme for shallow water and the new lateral drag parameterization for deep water leads to an improved and realistic landfast ice distri bution in most marginal seas in the Arctic.These results suggest that multiple mechanisms are at work to create and maintain landfast ice in marginal seas
This work has been published:https://doirg/101029/2022JC018413 Short-bio:
Yuqing Liu is a PhD.candidate at Alfred Wegener Institute for Polar and Marine Re search in Germany(Supervisor: Dr.Martin Losch).Her research interest is landfast ice dynamics in the Arctic.The recent work implements a new parameterization in MITgcm to improve the simulation of landfast ice area in the sea ice model and the undergoing work explores the effects on the hydrography in the Arctio of the neparametrization
