How do climate-driven shifts in phytoplankton composition influence carbon and nitrogen uptake and recycling along the west Antarctic Peninsula?

Project summary: Biological carbon and nutrient uptake and recycling will be examined at the west Antarctic Peninsula in relation to phytoplankton biomass and species composition.

Background and rationale:
The west Antarctic Peninsula (WAP) region has experienced significant warming of the atmosphere and ocean since the 1950s with a concurrent reduction in the extent and duration of sea ice cover over the satellite period. These trends have slowed down since the 2000s, reflecting substantial natural internal variability in the regional climate system superimposed on longer-term trends related to climate change.

Climate-driven changes in sea ice dynamics and the physical and chemical properties of the upper ocean have significant implications for primary production, influencing both the magnitude and species composition of phytoplankton blooms, with important consequences for the entire food web. Primary production and phytoplankton species composition have a strong impact on the biological uptake of the major nutrients nitrate, phosphate and silica, as well as the greenhouse gas carbon dioxide. The central objective of this PhD project is to quantify the biological uptake of carbon and dissolved nitrogen forms during the summer growing season at the WAP, and its variability with the magnitude and species composition of phytoplankton blooms. Variability in these uptake terms is important for regional biogeochemical cycling due to their influence on WAP shelf nutrient budgets, fluxes and the air-sea exchange of CO2. Understanding how primary production and phytoplankton species composition influence carbon and nitrogen uptake dynamics over a range of summertime conditions will inform projections of future biogeochemical changes along the WAP as climate change and variability proceed.

This PhD project will involve austral summer fieldwork at the WAP and participation in the large international research effort underway in this region, offering significant opportunities for national and international collaboration.

Key research questions:
1) How do carbon and nitrogen uptake rates vary during the summer growing season along the WAP?
2) What is the relative importance of new and regenerated production in the WAP region during summer?
3) How tightly coupled are carbon and nitrogen uptake and cycling in the WAP region during summer?
4) How does carbon and nitrogen recycling vary between different phytoplankton communities?

Requirements: The successful applicant will have at least a 2.1 degree in a relevant scientific discipline. All training will be provided, but experience of scientific fieldwork and/or laboratory techniques would be an advantage. Whilst this project does not require strong pre-existing quantitative skills, a working knowledge of MS Excel as well as programming languages such as R would be beneficial.

Full details: https://www.ed.ac.uk/e4-dtp/how-to-apply/our-projects/project/94

How to apply: http://www.ed.ac.uk/e4-dtp/how-to-apply