One of the fundamental difficulties in modeling weather and climate is that we must account for processes ranging from sub-meter scales up to global scales, with lifetimes ranging from seconds to months or even years. Processes at different scales are also coupled: global and regional weather and climate cannot be understood without accounting, for example, for exchanges of heat, momentum and gasses at the air-sea interface, which are mainly the result of small-scale processes (turbulence in the lower atmosphere and the upper ocean, ocean waves, etc.). As it is impossible to numerically simulate the full range of scales, we rely on simplified models (“parameterizations”) for what happens at the small, unresolved, scales. Developing and improving these small-scale models depends heavily on observations. For the case of air-sea interactions, happening at 70% of the Earth’s surface, numerical weather prediction and new generation climate models are reaching resolutions that are beyond our current observational capabilities. Filling this gap is one of the main purposes of the Harmony
