Periodic Reporting for period 2 - MESOPP (Mesopelagic Southern Ocean Prey and Predators)
Période du rapport: 2017-12-01 au 2019-05-31
During the first half of the project, project partners have been working on the production of standardized reference datasets of 38 kHz acoustic data in three different regions of the Southern Ocean (Indian, Pacific and Atlantic). A common methodology and processing of data is developed for facilitating the use of these data in the modeling, based on international standards for acoustic data (ICES) and metadata formats (CF). These reference datasets are used to validate different modeling approaches and help to provide biomass estimates. The first version of the CIS has been released as planned ( Nov 2017). It provides publicly the series of bio-acoustic transects from the reference datasets using the same resolution and format. Each transect is detailed by its metadata. One additional dataset of collocated profiles of oceanographic variables and acoustic data provide precious information to analyse and model the vertical structure of the mesopelagic ocean. Selected data can be downloaded by registered user from a ftp data store.
A series of models was selected (SEAPODYM, ATLANTIS, SIZE-BASED, ECOPATH) for the SO domain. To assist in evaluation and intercomparison, a documentation of each model was prepared that included the approaches for standardisation and protocols to be used. From this documentation it was possible to define metadata and format needed to feed the CIS catalogue. As a first demonstration, outputs from a simulation with one model (SEAPODYM) was uploaded in the CIS. It provides micronekton biomass estimate for the SO at a resolution of ¼° x week for the period 2011-2016. It is expected to deliver a new simulation with a revised parameterisation achieved thanks to the assimilation of acoustic data in the model. Good progresses have been achieved in the methodology proposed to convert acoustic signal in biomass.