Overfladetemperatur

Overfladetemperatur, commonly translated as surface temperature, is the temperature of the outermost layer of a material or medium at its boundary with the surroundings. In meteorology and climatology it usually refers to the temperature of the Earth’s surface, including land, water, and vegetation, as distinct from the temperature of the air close to the surface.

Measurement and interpretation of surface temperature vary by context. Ground-based instruments measure the temperature near the surface, but the term surface temperature often denotes the skin temperature of the surface itself. Remote sensing from satellites or aircraft infers surface temperature by detecting thermal infrared radiation or microwave emissions emitted by the surface. In this sense, two main categories are land surface temperature (LST) and sea surface temperature (SST). LST and SST can differ from near-surface air temperature due to factors such as solar heating, emissivity, wind, and the thermal properties of the surface.

Units commonly used are Celsius or Kelvin, with Fahrenheit used in some regions. Surface temperature is influenced by radiative balance, albedo, emissivity, convection, wind speed, soil moisture, and vegetation cover. Diurnal and seasonal cycles cause substantial fluctuations, and water bodies exhibit different dynamics because of their higher heat capacity and mixing.

Applications of surface temperature data include weather forecasting, climate monitoring, agriculture, and urban heat studies. SST, in particular, is a critical variable in oceanography and climate phenomena such as El Niño and La Niña. Measurement challenges include sensor bias, assumptions about emissivity, pixel mixing in remote sensing, and distinguishing skin temperature from bulk temperature in the near-surface layer.