“Investigation of the snowpack derived organic carbon in maritime Antarctica; characteristics, dynamics and processes influencing Fe, N and P delivery to terrestrial and marine ecosystems“


Funding source: Collaborative Antarctic Science Scheme CASS-120

P.I.: Dr Aga Nowak
Department of Geography,
The University of Sheffield,
Winter Street,
S10 1JB,
Sheffield
Contact: a.nowak@sheffield.ac.uk

Predictions of climate change draw increasing scientific attention to the fertilisation potential of the Antarctic Peninsula for the Southern Ocean and consequently global ecosystems. Although the scientific community is becoming aware of a marked heterogeneity in the chemical signature of meltwaters and the snowpack across Antarctica, we are still estimating nutrient fluxes from the Antarctic continent based on point measurements and assumptions that nutrient production is uniform across the whole region.

Our understanding of the sources and processes influencing concentrations of nutrients is also far from complete. For example, it is widely accepted that ice-melt nutrients take part in microbially mediated reactions yet, nutrient dynamics in snow are usually thought to be associated with inorganic processes and the microbial contribution remains virtually unexplored. Such a knowledge gap is surprising, considering the efforts put into constraining Antarctica’s contribution to the global carbon cycle, reconstructing past climates from ice core records, or predicting changes in terrestrial and marine ecosystems as Antarctica responds to climate warming.

This project will therefore define for the first time the linkages between physical conditions, microbial activity, and the fertilisation potential of meltwaters from the Antarctic Peninsula snowpack. To fully appreciate heterogeneity of this vast environment, and to understand how physical conditions constrain nutrient turnover by resident microbial communities, the fieldwork will be performed at five locations on the Antarctic Peninsula (Rothera, Anchorage Island, Leonie Island, Fossil Bluff and Mars Oasis) throughout the whole 2016/2017 Antarctic summer season. Over 200 snowpack, meltwater as well as snow-air samples will be collected throughout the campaign and then pre-processed at Bonner Laboratories at British Antarctic Survey research station. The samples will be then transported to the UK on James Clark Ross for further analyses at the Department of Geography, the University of Sheffield.

The study aims to advance our knowledge of the Antarctic contribution to the global carbon cycle and provide crucial data for more accurate predictions of the effects of changing climate on the globally important Southern Ocean.

Antarctic