ACUSAT (Remote sensing of mesoscale oceanic processes by acoustics and satellite sensors – a new approach to understand biophysical coupling) is a joint project between Institiute of Marine Research (IMR) and Nansen Environmental and Remote Sensing Center. ACUSAT aims to get a better understanding of the biophysical coupling within eddies through an integrated study using acoustic instrumentation, remote sensing, and numerical modeling. This promising new approach is used to detect and map eddies along the Norwegian continental shelf and slope.

Mesoscale eddies are important for the ocean circulation and are considered important for the open sea productivity. The basic processes behind are difficult to study and are poorly understood mainly due to inadequate spatio-temporal coverage offered by traditional methodologies. Recent studies have showed that surface observation of eddies as recorded by satellites can be combined with full depth coverage vessel acoustic sensors. In concert the two methods create a new powerful tool to study biophysical interaction in eddies. Sea surface altimetry or ocean colour data combined with acoustics records of biomass may uncover biophysical interactions within eddies, and help understanding their importance for marine bioproduction. Advanced biological sampling can be designed to collect marine life thus giving precise information about spatio-temporal distribution adequate for modeling of biophysical coupling far beyond traditional sampling approaches.

An integral part of the methodology is the application of physical-biological models to study the bio-physical interactions. The models will help understanding how different types of eddies influence production and thus giving insight to how eddies contribute to the distribution and production of biomass in the open ocean.

AcuSat is funded under the NFR HAVKYST program from 2009 to 2011.