Simple rules govern the patterns of Arctic sea ice melt ponds

TL;DR

This paper introduces a simple geometric model that accurately reproduces the patterns of Arctic sea ice melt ponds, revealing their consistent scale and connectivity across years and ice types, and aiding future climate predictions.

Contribution

The study presents a minimalistic void model based on overlapping circles that captures key features of melt pond geometry and abundance, improving understanding of sea ice melt feedbacks.

Findings

The model reproduces pond size and connectedness over six orders of magnitude.

Pond scale and connectedness are consistent across different years and ice types.

Ponds resemble percolation clusters near the percolation threshold.

Abstract

Climate change, amplified in the far north, has led to rapid sea ice decline in recent years. In the summer, melt ponds form on the surface of Arctic sea ice, significantly lowering the ice reflectivity (albedo) and thereby accelerating ice melt. Pond geometry controls the details of this crucial feedback; however, a reliable model of pond geometry does not currently exist. Here we show that a simple model of voids surrounding randomly sized and placed overlapping circles reproduces the essential features of pond patterns. The only two model parameters, characteristic circle radius and coverage fraction, are chosen by comparing, between the model and the aerial photographs of the ponds, two correlation functions which determine the typical pond size and their connectedness. Using these parameters, the void model robustly reproduces the ponds' area-perimeter and area-abundance relationships over more than 6 orders of magnitude. By analyzing the correlation functions of ponds on several dates, we also find that the pond scale and the connectedness are surprisingly constant across different years and ice types. Moreover, we find that ponds resemble percolation clusters near the percolation threshold. These results demonstrate that the geometry and abundance of Arctic melt ponds can be simply described, which can be exploited in future models of Arctic melt ponds that would improve predictions of the response of sea ice to Arctic warming.