Abstract
The sea surface and air–sea exchange processes have been identified as essential for both short- and long-term atmospheric and ocean forecasts. The two phases of the fluid layer covering our planet interact across a vast range of scales that we need to explore to achieve a better understanding of the exchange processes. While satellites provide a distributed large-scale view of the sea surface situation, highly detailed measurements, e.g., from oceanographic towers, are necessarily local. An intermediate solution can be provided by swarms of miniature surface buoys that measure waves and other key parameters. As size, weight, and cost are reduced, these can be deployed in large numbers to investigate specific processes that are at present only crudely parameterized in our models, also because of the scarcity of good measurements. Perhaps the most crucial process is white capping in stormy conditions, where air–sea exchanges are enhanced by one or two orders of magnitude. Other applications include wave–current interactions, wave–ice interactions, and plunging breakers in the coastal zone. Stimulated by a dedicated workshop, we summarize here the main findings and possibilities derived from the different approaches and, in particular, the state of the art for a selection of miniature buoys. We list the presented solutions, as well as other, similar and larger, buoys, with their main characteristics and range of application. We describe the various possibilities of practical use and the scientific and engineering problems to be solved. Looking to the future, we also point out where the present technological improvements are leading to.