Anticipated capabilities of the ODYSEA wind and current mission concept to estimate wind work at the air-sea interface

The kinetic energy transfer between the atmosphere and oceans, called wind work, affects 1 ocean dynamics including near-inertial oscillations and internal gravity waves, mesoscale eddies, and 2 large-scale zonal jets. For the most part, recent numerical estimates of global wind work amplitude are 3 almost 5 times larger than those reported 10 years ago. This large increase is explained by the impact 4 of the broad range of spatial and temporal scales covered by winds and currents, the smallest of 5 which have only recently been uncovered by increasingly high resolution modeling efforts. However, 6 existing satellite observations do not fully sample this broad range of scales. The present study 7 assesses the capabilities of ODYSEA, a conceptual satellite mission to estimate the amplitude of wind 8 work in the global ocean. To this end, we use an ODYSEA measurement simulator fed by the outputs 9 of a km-scale coupled ocean-atmosphere model to estimate wind work globally. Results indicate that 10 compared with numerical truth estimates, the ODYSEA instrument performs well globally, except 11 for latitudes north of 40◦N during summer due to unresolved storm evolution. This performance is 12 explained by the wide-swath properties of ODYSEA (a 1,700 km wide swath with 5 km posting for 13 winds and surface currents), its twice-a-day (daily) coverage at mid-latitudes (low latitudes), and the 14 insensitivity of the wind work to uncorrelated errors in estimated wind and current.