ABACUS-3: Third Algerian BAsin Circulation Unmanned Survey

User: Giorgio Budillon, Università degli Studi di Napoli “Parthenope”, Italy

Hosting infrastructure: SOCIB glider facility, Spain

Main Objectives

Just after the Alboran Sea, the Algerian Basin (AB) is the first wide basin crossed by Atlantic Water entering the Mediterranean Sea. It is dominated by the presence of energetic mesoscale structures that usually develop from meanders of the Algerian Current to isolated cyclonic and anti-cyclonic eddies.

The project aims at assessing the importance of a new monitoring line across the AB between Palma de Mallorca and the Algerian Coast and will contribute to data collection in the Southern European Seas, one of the main EU maritime policy objectives, as outlined in the Marine Strategy Framework Directive (MSFD).

The realization of a new glider mission, along the Sentinel-3 groundtracks #57 and #713, will enrich the dataset previously collected in this area (Autumn 2014 and 2015), taking into account the lesson learned (i.e., improving the optimized synopticity of glider measurements and satellite overflights, the downcast/upcast data sampling strategy, etc.) also focusing on possible inter-annual and multiplatform comparisons.

Furthermore, the high resolution of glider data will allow one to investigate smaller spatial scales. In fact, despite the large bibliography about the circulation of the entire Mediterranean Sea and its sub-basins, knowledge about mesoscale structures like eddies is still incomplete because of their intrinsic time scales and of the difficulties in their sampling. Recently, the merging of glider measurements and new generation remotely sensed data, offered the opportunity to study some of the eddies’ characteristics, such as radius, track and rotational speed. Nevertheless, the lack of high resolution in situ data, through eddies and along their edges, still remains a main concern. ABACUS-3 also aims at filling this gap intercepting any mesoscale structures in the AB eventually identified during the mission.

Finally, the collected high resolution glider observations is expected to be used for the validation of the new Sentinel-3 along-track (L3) and gridded interpolated (L4) altimetry products in the western Mediterranean Sea.

DATA: http://thredds.socib.es/thredds/catalog/auv/glider/sdeep01-scb_sldeep001/L2/2016/catalog.html?dataset=auv/glider/sdeep01-scb_sldeep001/L2/2016/dep0021_sdeep01_scb-sldeep001_L2_2016-11-04_data_dt.nc

Project Report: ABACUS3_report_final.pdf