NorArgo2 is an observation system for the northern seas that consists of oceanographic battery powered floats, Argo floats. The Argo floats are mainly located in the deep water drifting with the currents there. The float has a buoyancy equal to the surrounding water masses and it adjusts its depth by changing its buoyance using a hydraulic pump system. With 5-10 day intervals, they rise from the depth to the surface while taken measurements during the ascent. The floats are equipped with sensors for measuring pressure, temperature, salinity, oxygen concentration and other biogeochemical parameters that are important for the description of the ecosystem. When a float surfaces the data are transmitted to land via satellite. Afterwards it descends to the deep ocean again until it ascends again after 5-10 days. This can continue for several years (approximately 150-200 cycles). Data from the floats will be in near-real time available to all users via the Internet, within 24 hours after the observations have been taken. All collected data are manually controlled to ensure that the data are of high scientific quality. The goal is to have over 30 floats drifting in the Nordic Seas, the Barents Sea and the Arctic Ocean, that will be part of the European Argo infrastructure, Euro-Argo, which represents the European contribution to the global Argo.
Within the project period NorArgo2 has so far (2018-2022) deployed 56 Argo floats. Today there are 45 Norwegian Argo floats that are operative that makes Norway as the leading nation within the Nordic Seas. Norway is also the only nation that has Argo floats with biogeochemical sensors and deep floats that can reach 4000 m depth in the Nordic Seas. These data are important to understand the processes in the ocean and for the research on the ecosystem in the ocean. A better understanding of the state of the sea and of the global climate change is also important for Norway to succeed in management of marine areas and resources.
NorArgo2 will establish a sustainable and cost-effective observing system for the Arctic, by operating and maintaining an array of 32 autonomous vertical profiling floats, Argo floats, in the Arctic. They will provide high-quality and near-real time vertical profiles of pressure, temperature, salinity and additional biogeochemical parameters, as well as drift velocity of the floats with ~weekly temporal resolution. NorArgo2 will extend the existing infrastructure NorArgo, which is on the Norwegian infrastructure roadmap, with improved grid coverage, additional biogeochemical sensors, and into new areas such as the Barents Sea and Arctic Ocean. It will provide validated data sets that are freely and easily accessible. NorArgo2 will apply for full membership in the Euro-Argo ERIC, contribute to the Euro-Argo ERIC Roadmap and the international core and biogeochemical (BGC) Argo programmes, and the extension into the deep ocean. The Argo floats will be operating and deployed in the Nordic Seas, the Barents Sea and the European part of the Arctic Ocean. A deployment of approximately 13 floats per year is required to keep the target of 32 operating floats all the time. Argo floats with different equipment and properties will be used. These include Argo floats with standards sensors (pressure, temperature and salinity), Argo floats with additional biogeochemical sensors (for oxygen, chlorophyll, nitrate, pH, suspended particles, and irradiance), and Argo floats for the deep ocean. NorArgo2 will make Argo attractive for new users, both scientists and non-scientists. Hence, NorArgo2 will provide Norway with state-of-the-art instrumentation and cost effective tools that will provide the observations required to monitor and understand climate change and its biogeochemical and ecosystem consequences in Norwegian and adjacent water.