New high-resolution observations of ocean surface current and winds from innovative airborne and satellite measurements

High-resolution satellite images of ocean colour reveal a multitude of oceanic features at scales below 10km. Small eddies, whirls and filaments permeate the global ocean but are particularly frequent near current jets, mesoscale eddies, in coastal seas and near sea ice. Recent research show that these small-scale processes play a critical role in the global climate system by modulating interactions between the atmosphere, ocean, land and cryosphere - impacting vertical exchanges of heat, gases, freshwater and nutrients between the surface and the ocean interior and horizontal transport pathways. However, today's knowledge of these processes stems mainly from models, with little observational data available for validation. Measuring small scales in situ is extremely challenging, expensive and rare. This project investigates a new type of ocean observations from the innovative OSCAR airborne system that images ocean current and wind fields at 1km resolution or finer. The project analyses data from two recent airborne campaigns in France and the Netherlands, comparing with high-resolution models, in situ sensors and satellites. The project will demonstrate the added-value of OSCAR data to understand and model small-scale ocean dynamics, and strengthen the scientific motivation of the Earth Explorer 11 SEASTAR mission candidate (Gommenginger et al., 2019).