UCL Earth Sciences


Connor Nelson

“Towards mitigating snow-induced sea ice thickness biases through investigating the properties of snow on sea ice and understanding the associated interactions with microwave radiation.”

PhD project title:

Investigating the Arctic sea ice snowpack and modelling its interaction with microwave radiation.

Connor Nelson
Project description:

Sea ice is an important component of the earth system which acts to cool the planet whilst regulating the exchange of momentum, heat, and moisture between the atmosphere and ocean. The snowpack that accumulates upon sea ice both impacts the evolution of the ice below and hinders our ability to accurately measure its thickness on a pan-Arctic scale. But despite the two forming an inherently coupled system, snow-on-sea-ice remains poorly understood.

The layered snowpack biases sea ice thickness retrievals from radar (microwave) altimeters by three main processes: (1) slowing down radar-wave propagation, (2) changing the radar-wave dominant scattering horizon, and (3) changing the hydrostatic equilibrium of the system, thus altering the sea ice freeboard.

The goal of this project is to mitigate the above biases to give a more accurate depiction of the state of Arctic sea ice and help us to better predict its future. To achieve this, I will use sophisticated snow accumulation models to improve our understanding of the stratigraphy and properties of the snowpack, including how it has changed across the satellite era. Furthermore, by modelling how the different layers interact with microwave radiation, I aim to develop a forward simulator that deduces the most likely origin of altimetric radar-wave backscatter.