On the statistical properties of sea ice lead fraction and heat fluxes in the Arctic

• Main Authors: Ólason, Einar Örn, Rampal, Pierre, Dansereau, Véronique
• Format: Text
• Language: English
• Published: 2020
• Subjects: Arctic; Arctic Ocean; Sea ice
• Online Access: https://doi.org/10.5194/tc-2020-13; https://tc.copernicus.org/preprints/tc-2020-13/

In this paper we explore several statistical properties of the observed and simulated Arctic sea-ice lead-fraction, as well as the statistics of simulated Arctic ocean-atmosphere heat fluxes. We first show that the probability density function (PDF) and the monofractal spatial scaling of the observed lead fraction in the Central Arctic are both well represented by our model, neXtSIM. Given that the heat flux through leads may be up to two orders of magnitude larger than that through unbroken ice we then explore the statistical properties (PDF and spatial scaling) of the heat fluxes simulated by neXtSIM. We demonstrate that the modelled heat fluxes present a multifractal scaling in the Central Arctic, where heat fluxes through leads dominate the high-flux tail of the PDF. In the Central Arctic, the high-flux tail of the PDF is dominated by an exponential decay, which we attribute to the presence of coastal polynyas. Finally, we show that the scaling of simulated lead fraction and heat fluxes depend weakly on the model resolution and discuss the role sub-grid scale parameterisations of the ice heterogeneity may have in improving this result.