Arctic amplification: How feedback loops chained in tandem amplify Arctic responses to warming and the role of human impacts

Johnna Holding, Aarhus University, Aarhus C, Denmark, Victor Eguíluz, IFISC Institute for Cross-Disciplinary Physics and Complex Systems, Palma de Mallorca, Spain, Kristina Brown, Fisheries and Oceans Canada, Institute of Ocean Sciences, Sidney, BC, Canada, Uma Suren Bhatt, University of Alaska Fairbanks, Fairbanks, AK, United States, Henry Huntington, Self Employed, Washington, United States and Carlos M Duarte, King Abdullah University of Science and Technology, Red Sea Research Center, Thuwal, Saudi Arabia
The Arctic marine ecosystem is heavily impacted by anthropogenic climate change. Warming is occurring at 2-3 times the global rate and causing such extensive ice-sheet and sea-ice loss that models struggle to predict the severe changes in the cryosphere. The term “Arctic amplification” has been used to describe these precipitous changes which are caused by several positive feedback mechanisms in the physical system (e.g. reduction in ice albedo effect). However, these changes have, themselves, lead to changes in the Arctic marine ecosystem, as well as in human operations in the Arctic, resulting in increased fishing, shipping and mineral and energy development. These chained feedback mechanisms operating in tandem may be further amplifying or contain buffering loops, which are capable of dampening amplification. In this study we perform a formal analysis of the architecture of a network of direct interactions which drives the Arctic Ocean social ecosystem, and highlight the presence of amplification and damping feedback loops either acting alone or in tandem to stabilize or generate instabilities in the system. We use a parsimonious representation of a network of interactions, based on a review of evidence in the published literature, and then conduct an structural analysis of three scenarios: (1) a preindustrial Arctic Ocean, devoid of human impacts other than activities of indigenous people, and two scenarios of an Arctic Ocean in the Anthropocene, (2) human operation in the Arctic aiming at maximizing resource extraction, and (3) sustainability-driven human operations in the Arctic. Our analysis of scenarios for the Anthropocene Arctic Ocean show that society can play alternative roles, either amplifying change when driven by resource extraction or adding to the biological elements of the ecosystem in buffering change when driven by sustainability.