New technologies for marine research: 4 years of glider activities at IMEDEA-TMOOS

Abstract

Underwater gliders are a special case of underwater autonomous vehicles designed to observe vast areas of the interior ocean. Buoyancy control allows vertical motions in the water column. In addition, using their hydrodynamic shape and small fins, they can project the vertical buoyancy force to move horizontally. This combination of vertical and horizontal movements makes the glider follow a sawtooth pattern. The nominal horizontal speed is about 1 km/h. The long autonomy period at sea is the main advantage of this platform. Gliders allow autonomous and sustained collection of CTD data and biogeochemical measurements (fluorescence, oxygen, turbidity, etc) at high spatial resolution (~0.5 km) and at low cost compared to conventional methods. We will present recent results from glider missions in the Western Mediterranean that confirm the feasibility of using coastal and deeps gliders to monitor mesocale processes in the upper ocean. Gliders have also proved to be highly robust platforms to monitor the ocean even under adverse meteorological conditions and/or in really challenging oceanic areas such as the Alborán Sea. The Glider Unit at IMEDEA Department of Marine Technologies, Operational Oceanography and Sustainability (TMOOS) is operating gliders since 2007. The actual fleet consists of 4 Slocum gliders, one is limited to 200 m depth and three can reach 1.000 m depth. IMEDEA‐TMOOS gliders have carried out about 15 gliders missions in the western Mediterranean Sea and gathered ~6200 conductivity‐temperature‐depth and biogeochemical profiles