Alexander Hayward

Masters project title: A study on how changing environmental parameters in the Arctic Ocean influence in-ice biota over a temporal scale

Supervisors: Prof Julienne Stroeve (UCL), Dr Giulia Castellani (AWI), Dr Jeremy Wilkinson (BAS)

The Arctic is in a state of rapid change. This is depicted by the severe reduction in sea ice thickness, age and extent of cover. Most of my background is with trophic interactions between the base of the ecosystem and how this bottom up control cascades through the foodweb. My Masters project focuses on the interactions between physics and biology, and is part of the Eco-Light project.

Due to seasonal variations of incoming solar radiation, we are investigating how in-ice algae respond to differing light regimes and its influence on the Arctic’s carbon budget. The focus of our study will provide insight on how changing environmental parameters during the transitional period of summer to winter will influence sea-ice algal biomass.

Spectral data acquired from the field during summer 2018 will be coupled with the HPLC analysis of ice cores (facilitated by KOPRI) to create a proxy of biomass using chlorophyll’s absorption spectra of 450nm alongside the absorption wavelengths of accessory pigments. To complement the bio-physical measurements we have taken taxonomy and primary production samples. We aim to create a model that will determine in ice biomass from parameters such as incoming solar radiation, salinity, ice thickness and temperature.

To gain an understanding of how conditions will change over the transition of summer to winter, a bio-optical buoy (IMB-072) has been deployed on an ice-floe in the Central Arctic Ocean. IMB-072 is equipped with; TriOS hyperspectal radiometers for irradiance values under ice and above ice; an oxygen-optode for primary production; micro-cat for salinity; and an eco-triplet to gain biomass values.

Eco-Light is co-funded by the German Federal Ministry of Education and Research and by NERC.