The future Barents Sea—A synthesis of physical, biogeochemical, and ecological changes toward 2050 and 2100

Abstract

The Barents Sea is a hotspot for ongoing Arctic climate change, manifested in a rapid warming of the ocean and the atmosphere and a strong decline of the winter sea-ice cover. These changes in the physical environment have large consequences for marine ecosystems, including commercial fish populations. In a warmer future climate, both physical and ecological changes are expected to intensify. Here, we provide a first comprehensive overview of future climate change projections for the Barents Sea, and the associated physical, biogeochemical, and ecological consequences based on climate models and end-to-end ecosystem models. We also discuss potential future changes in human activities and their impacts, including changes in shipping activity and contaminants. We analyze results for two time horizons—the near-future (2040–2050) and the far-future (2090–2100)—and for two different emission scenarios: one with moderate future greenhouse gas emissions (SSP2-4.5) and one high-emission scenario (SSP5-8.5). The projections show that the future Barents Sea will be warmer, less ice-covered, more acidic, and more productive, with fish populations and spawning sites moving northward. There are small differences in multi-model mean physical and biogeochemical projections between the two emission scenarios by 2050, while large scenario differences emerge toward the end of the century. The implications of these results are far-reaching, including identifying the sensitivity of ecosystem change to future emissions, informing regional management strategies, and potentially identifying needs for adaptation to changes already likely to occur.