Insights into climate change in the Arctic Ocean: disentangling carbon-climate complexities in Arctic sediments using hyperspectral core imaging

Arctic warming is disrupting the Arctic carbon cycle with the potential to accelerate Climate Change and amplify its impacts.

Coastal erosion and thawing permafrost are releasing Green House Gases into the atmosphere while enhanced organic matter (OM) delivery to the ocean is driving ocean acidification.

Analysis of marine sediment cores allows us to quantify burial rates and degradation processes critical for understanding the fate and impact of remobilized carbon along the land-ocean continuum.

Furthermore, marine sediments record how OM fluxes and sources have changed on multi-decadal to millennial timescales in response to natural and anthropogenic climate change.

However, quantifying the amount, type and source of OM requires time-consuming analyses and can be difficult to perform at high temporal and/or spatial scales.

Hyperspectral imaging (HSI) of marine and lacustrine sediment cores is an exciting new research frontier for rapid, non-destructive biogeochemical characterization. HSI combines the power of classical reflectance spectroscopy with high-resolution line scanning cameras.

Each pixel of the imaged core surface contains a spectral profile of reflected light across the visible to near-infrared range (400-2500 nm).

As different minerals and organic compounds absorb light in specific wavelengths, spectral shapes and diagnostic absorption band responses are used to quantify the biogeochemical composition of scanned sediments.

This project will develop HSI routines to quantify the amount and type OM in continental shelf sediments from the Arctic Ocean.

We will focus on the Canadian Beaufort Sea, where the Mackenzie River delivers the largest sedimentary load of all Arctic rivers, and rates of coastal erosion are among the highest across the Arctic.

The project combines expertise on automated core imaging at Stockholm University, and the analysis of organic biomarkers at the National Research Council of Italy‘s Institute of Polar Sciences.