Characterizing sea ice surface morphology using high-resolution IceBridge data

Tuesday, 16 December 2014
Alek Petty1,2, Sinead L Farrell1,2, Thomas Newman1,2, Nathan T Kurtz3, Jacqueline Richter-Menge4, Michel Tsamados5 and Daniel Lee Feltham5, (1)NOAA Center for Weather and Climate Prediction, College Park, MD, United States, (2)University of Maryland, Earth System Science Interdisciplinary Center, College Park, MD, United States, (3)NASA Goddard, Greenbelt, MD, United States, (4)USA CRREL, Hanover, NH, United States, (5)University of Reading, Centre for Polar Observation and Modelling, Department of Meteorology, Reading, United Kingdom
Sea ice pressure ridges form when ice floes collide while drifting under the combined forces of atmospheric drag, oceanic drag and ice-ice interaction. Sea ice ridges, in-turn, affect the resultant form drag on the sea ice cover and thus impact the fluxes of momentum and heat between the atmosphere and ocean. Here we present initial results of a new sea ice ridge detection approach that utilizes high resolution, three-dimensional ice/snow surface elevation data from the NASA Operation IceBridge Airborne Topographic Mapper (ATM) laser altimeter merged with coincident high-resolution imagery from the Digital Mapping System (DMS).

We derive novel information regarding sea ice deformation across a variety of ice types and regimes. Statistical information regarding sea ice ridges (height/frequency/orientation) and floe edges (freeboard height) are presented for several IceBridge flight lines. These novel characterizations of sea ice surface morphology will be used to validate and inform drag parameterizations in state-of-the-art sea ice models. Furthermore, they will advance our ability to quantify uncertainties introduced by pressure ridges in the estimation of sea ice freeboard/thickness from airborne and satellite altimeters.