Warming in the Arctic Captured by productivity variability at an Arctic Fjord over the past two centuries.

• Main Authors: Vikash Kumar, Manish Tiwari, R Rengarajan
• Format: Article
• Language: English
• Published: Public Library of Science (PLoS) 2018-01-01
• Series: PLoS ONE
• Online Access: http://europepmc.org/articles/PMC6093672?pdf=render

Arctic fjords feature among some of the most climate-sensitive regions on the planet. The site of this study-Kongsfjorden-is one such fjord in which sedimentation and sediment geochemistry reflect climate-mediated changes in glacial melt and marine primary productivity. Here, we have shown that the fjord is particularly sensitive to the changing melt dynamics of the surrounding glaciers which are a direct consequence of warming/cooling in the region and is reflected in the productivity at the fjord. Warming increases meltwater influx into the fjord leading to enhanced turbidity which results in lower productivity. A multi-proxy study (sedimentary organic matter content, carbon and nitrogen isotope ratios, and microfossil abundance) using a 21 cm long sediment core from the Kongsfjorden helped us reconstruct warming driven melt-dynamics history for the past two centuries. Proxy data show a general decreasing trend in productivity along with a few excursions over the last two centuries. Warming driven glacial-melt dynamics appears to be the dominant control on productivity throughout the span of the core.