Late twentieth century increase in northern Spitsbergen (Svalbard) glacier-derived runoff tracked by coralline algal Ba/Ca ratios ...

• Main Authors: Hetzinger, Steffen, Halfar, Jochen, Zajacz, Zoltan, Möller, Marco, Wisshak, Max
• Format: Text
• Language: English
• Published: Humboldt-Universität zu Berlin 2021
• Subjects: Ba/Ca; Runoff proxy; Glacier; Freshwater; Coralline algae; Svalbard; 550 Geowissenschaften; Arctic; arctic cryosphere; glacier; Global warming; Spitsbergen
• Online Access: https://dx.doi.org/10.18452/26590; https://edoc.hu-berlin.de/handle/18452/27287

The Arctic cryosphere is changing rapidly due to global warming. Northern Svalbard is a warming hotspot with a temperature rise of ~ 6 °C over the last three decades. Concurrently, modelled data suggest a marked increase in glacier runoff during recent decades in northern Svalbard, and runoff is projected to increase. However, observational data from before anthropogenic influence are sparse and the potential effects on the surface ocean are unclear. Here, we present a 200-year record of Ba/Ca ratios measured in annual increment-forming coralline algae from northern Spitsbergen as a proxy for past glacier-derived meltwater input. Our record shows a significant increasing trend in algal Ba/Ca ratios from the late-1980s onwards matching modelled regional runoff data, suggesting a drastic increase in land-based runoff. The rate of increase is unprecedented during the last two centuries and captures the impact of amplified warming on the coastal surface ocean in the high Arctic. The algal Ba/Ca runoff proxy ...