Scales of Temporal and Spatial Variability of Land Surface Temperature

Scales of temporal and spatial variability of clear sky land surface temperature (LST) are empirically estimated using data of satellite and land surface observations. We discuss here: • Observation and statistical description of LST. We consider separately time dependent expected value, weather related fluctuations, and errors of LST observation. • Scale of temporal autocorrelation of weather related LST variations. It is estimated to be approximately equal to ~ 3 day, which corresponds to time scale of weather system variations. • Scale of spatial autocorrelation of weather related LST variations, which is about ~1000 km that is spatial scale of synoptic weather systems. • Seasonal and diurnal cycles in the expected value of LST. They are the main components of temporal variations of clear sky LST. • Scale of spatial variability in the expected value of LST. It is found to be much smaller compared to scale of spatial variability in weather related signal. • Effects of a pixel size averaging and satellite pixel position wobble is evaluated using theory of optimal averaging of meteorological fields developed by R.L. Kagan (1979) This information is needed for better understanding and interpretation of LST observation at the past, current and future Geostationary and Polar orbiters.