ALBERT

Description: Arctic sea ice is declining rapidly in extent and thickness, simplifying access to oil and gas fields, enabling trans-Arctic shipping and allowing storms to erode permafrost coasts. This in turn modifies the biogeochemical cycling of carbon and nutrients, intensifies land-ocean interactions, as well as it shifts the distribution of harvestable resources. Alarmingly, sea ice reductions are taking place more rapidly than predicted in any global climate model. This persistent mismatch between observed and predicted patterns makes planning activities in the Arctic challenging. Scientific knowledge of the evolving status of the Arctic Ocean, its surrounding land areas and the process-based understanding of the mechanics of change are urgently needed to make useful projections of future conditions throughout the Arctic region. Arctic in Rapid Transition (ART; http://www.iarc.uaf.edu/en/ART/) is an integrative, international, interdisciplinary, pan-Arctic network to study the spatial and temporal changes in biogeochemical cycling and ecosystem functions in the Arctic marine and coastal realm. ART has been developed and is still steered by early-career scientists. Since 2012 it is an official network of the International Arctic Science Committee (IASC). The first phase of ART (2010-2014) focuses on developing a formal network to bring together scientists working in different geographic and disciplinary areas who share a common interest in improving our understanding of Arctic change. An ART Science Workshop will be held 21-24 October 2014 in Plouzané, France, in collaboration with the Association of Polar Early Career Scientists (APECS), the Permafrost Young Researchers Network (PYRN) and the European Institute for Marine Studies. This international workshop entitled “Integrating spatial and temporal scales in the changing Arctic System: towards future research priorities” (ISTAS) will aim at drafting research priorities from an early to mid-career perspective that will feed into the third International Conference on Arctic Research Planning (ICARP III) in Toyama, Japan in 2015. This workshop will bring together about 60 early career, mid-career and senior scientists from different Arctic research areas including cryosphere, terrestrial, marine, atmosphere, and socio-economic topics to ensure knowledge transfer across generations and disciplines. The second phase of ART (2014-2018) will be centered on active data collection, such as through the TRANSSIZ expedition planned on the RV ‘Polarstern’ in 2015. The final phase of ART will be a synthesis stage, so that the legacy of ART will be a coherent set of knowledge, which would feed into physical-biological models at various scales in order to develop more robust scenarios regarding the future state of Arctic coastal and marine ecosystems, their productive capacity, how they impact the dynamics of greenhouse gases, as well as their role in global processes.

Description: Although more than 700 sediment cores exist from the Arctic Ocean, the Plio-Pleistocene evolution of the basin and its marginal seas remains virtually unknown. This is largely due the shallow penetration of most of these records, and difficulties associated with deriving chronologies for the recovered material. The Integrated Ocean Drilling Program’s (IODP) Expedition 302 (Arctic Coring Expedition, ACEX) recovered 197 m of Neogene/Quaternary sediment from the circumpolar regions of the Lomonosov Ridge. As detailed analyses of this material emerge, research is beginning to formulate a long-term picture of paleoceanographic changes in the central Arctic Ocean. This paper reviews the ACEX Plio-Pleistocene age model, identifies uncertainties, and addresses ways in which these may be eliminated. Within the established stratigraphic framework, a notable reduction in the abundance of ice rafted debris (IRD) occurs in the early part of the Pleistocene and persists until Marine Isotope Stage 6 (MIS 6). Therefore, while global oceanographic proxies indicate the gradual growth of terrestrial ice-sheets during this time, IRD delivery to the central Arctic Ocean remained comparatively low and stable. Within the resolution of existing data, the Pleistocene reduction in IRD is synchronous with predicted changes in both the inflow of North Atlantic and Pacific waters, which in modern times are known to exert a strong influence on sea ice stability.