Fracture networks in sea ice

Jonas Nesland Vevatne,Alex Hansen,Reinert Korsnes,Eivind Rimstad,Sigmund Mongstad Hope

doi:10.3389/fphy.2014.00021

Abstract

Fracturing and refreezing of sea ice in the Kara sea are investigated using complex networkanalysis. By going to the dual network, where the fractures are nodes and their intersectionslinks, we gain access to topological features which are easy to measure and hence comparewith modeled networks. Resulting network reveal statistical properties of the fracturing process.The dual networks have a broad degree distribution, with a scale-free tail, high clusteringand efficiency. The degree-degree correlation profile shows disassortative behavior, indicatingpreferential growth. This implies that long, dominating fractures appear earlier than shorterfractures, and that the short fractures which are created later tend to connect to the longfractures.The knowledge of the fracturing process is used to construct growing fracture network (GFN)model which provides insight into the generation of fracture networks. The GFN model isprimarily based on the observation that fractures in sea ice are likely to end when hitting existingfractures. Based on an investigation of which fractures survive over time, a simple model forrefreezing is also added to the GFN model, and the model is analyzed and compared to the realnetworks.

Highlights

Fracturing and refreezing of sea ice in the Kara Sea is a complex process, depending on temperature, wind, currents, freshwater influx from two large rivers, salinity and even the Coriolis force
Sea ice fracture networks are accessible, and the processes occur on a time scale which is good for studying the dynamics
Whereas other work has focused on the geometrical properties of fracture networks of sea ice, in particular in connection with fractal scaling properties [18] our study is concerned with topological properties

Summary

INTRODUCTION

Fracturing and refreezing of sea ice in the Kara Sea is a complex process, depending on temperature, wind, currents, freshwater influx from two large rivers, salinity and even the Coriolis force. The present paper, focuses on the fracture–fracture interactions, and the object of our study is the network of fractures in sea ice on a geographical scale within the context of modern network theory. Whereas other work has focused on the geometrical properties of fracture networks of sea ice, in particular in connection with fractal scaling properties [18] our study is concerned with topological properties. Based on these data, we introduce a model for growth of fractures in ice which compares well with the data.

FROM FRACTURES TO NETWORK

ANALYSIS

SCALING AND GROWTH

CONCLUSIONS