This HF radar system is composed by two CODAR Seasonde antennas (transmit frecuency 4.525 MHz) and offers many benefits for the Basque Operational Oceanography Network such as: the improvement of the knowledge about surface currents and their forcing physical processes, marine safety, search and rescue, pollution response, validation and calibration of both hydrodynamic and pollutant drift forecasting models, data assimilation on progress, etc. The access from raw radial data to processes 2D surface current is provided for scientific and applied purposes (Coastal processes, marine safety, search and rescue, pollution response, etc).

This product of the Basque Operational Oceanography System (EuskOOS) consists on fields of the Lagrangian residual currents (LRCs) obtained from the gap-filling of HF radars data using the OMA methodology. To obtain the LRCs, the Lagrangian trajectories for particles evenly located in the HF radar grid are computed over 3 days. The initial and final positions of each particle are used to compute a Lagrangian residual vector (we call this “residual” because the contribution of the tidal component is filtered out by the time integration used) at the center of mass of its trajectory and then this Lagrangian vectors are re-interpolated to a regular grid. The LRC provide an estimation of the integrated transport due to the last 3-days total currents observed by the radar. This L4 data product can be delivered as a vector field or as a graphic map (of current vectors and streamlines).

The development of the ecosystem approach and models for the management of ocean marine resources requires easy access to standard validated datasets of historical catch data for the main exploited species. They are used to measure the impact of biomass removal by fisheries and to evaluate the models skills, while the use of standard dataset facilitates models inter-comparison. North Atlantic albacore tuna is exploited all year round by longline and in summer and autumn by surface fisheries and fishery statistics compiled by the International Commission for the Conservation of Atlantic Tunas (ICCAT). Catch and effort with geographical coordinates at monthly spatial resolution of 1° or 5° squares were extracted for this species with a careful definition of fisheries and data screening. In total, thirteen fisheries were defined for the period 1956-2010, with fishing gears longline, troll, mid-water trawl and bait fishing. However, the spatialized catch effort data available in ICCAT database represent a fraction of the entire total catch. Length frequencies of catch were also extracted according to the definition of fisheries above for the period 1956-2010 with a quarterly temporal resolution and spatial resolutions varying from 1°x 1° to 10°x 20°. The resolution used to measure the fish also varies with size-bins of 1, 2 or 5 cm (Fork Length). The screening of data allowed detecting inconsistencies with a relatively large number of samples larger than 150 cm while all studies on the growth of albacore suggest that fish rarely grow up over 130 cm. Therefore, a threshold value of 130 cm has been arbitrarily fixed and all length frequency data above this value removed from the original data set.