seasurface

Seasurface, or sea surface, refers to the interface between the ocean and the atmosphere. It is the uppermost layer of the ocean where exchanges of heat, momentum, and gases with the air occur. The seasurface includes the sea surface microlayer, a very thin region enriched with organic material and aerosols, which plays a role in air–sea interactions and gas exchange.

Key properties of the seasurface include sea surface height (SSH), sea surface temperature (SST), wind stress and surface currents, and surface roughness that arises from waves. The surface is affected by tides, wind, and waves, and supports a complex capillary and gravity wave spectrum. These factors influence heat and mass transfer between the ocean and atmosphere and affect climate and weather at larger scales.

Measurement and data: remote sensing dominates seasurface observation. Satellite altimetry provides SSH; infrared and microwave radiometry measure SST; radar and SAR reveal surface roughness and wind speeds. In situ observations from buoys, ships, and autonomous floats fill gaps. Data on the seasurface are essential for weather forecasting, climate monitoring, navigation, and modeling of ocean circulation.

Relevance: changes in the seasurface reflect and drive climate variability, including El Niño–Southern Oscillation and sea level rise. Sea surface properties are used in global climate models, ocean reanalyses, and environmental monitoring to assess heat content, evaporation, and gas exchange processes.