Antonio Novellino, Sylvie Pouliquen, Erik Buch and Patrick Gorringe

Climate change presents a major and growing challenge to the Arctic region, producing risks as well as opportunities. Access to accurate data and information has therefore never been more important to better understand critical physical, biogeochemical and biological processes. The spatial coverage of observing systems in the Arctic is scattered in time and space. Existing observations are of varying quality and made available on different timescales. Furthermore, a major part of marine observations are funded via fixed-term research projects, of which only one third openly share their data. In this context, EMODnet (Physics, Data Ingestion), Copernicus Marine Service In Situ Thematic Center (CMEMS INSTAC), Copernicus In Situ Coordination Group and EuroGOOS have joined efforts to establish a dedicated marine Arctic data portal with the purpose to: - Ease access to open and free marine Arctic in-situ data - Foster integration in European data aggregator infrastructures (CMEMS, EMODnet and SDN) - Unlock existing data from a variety of projects and initiatives not yet freely and openly exchanged - Provide support to share data through existing European data aggregators - Provide visibility to existing observing system platforms sharing data in the Arctic region In November 2020, the Arctic Data Portal (https://arctic.emodnet-physics.eu/), implemented under EMODnet Physics, was launched. It provides straightforward access to circumpolar datasets and metadata records from European data aggregators (CMEMS, SDN, EMODnet, Pangea) and other sources. The portal is composed of a map interface displaying the spatial distribution of observing platforms, a tool selecting by parameter and type of observing platform and plotting tools for displaying the datasets. The Arctic portalis similar to the SOOS-map portal that EMODnet Physics set up in collaboration with the Southern Ocean Observing System (SOOS). This has greatly improved access to key Southern Ocean datasets.