LOD – Length of Day

Length of Day (LOD) measures variations in the duration of a single Earth rotation relative to the standard 24 hours. It is an important Earth Orientation Parameter (EOP) linking the International Celestial Reference Frame (ICRF) and the International Terrestrial Reference Frame (ITRF). LOD variations reflect changes in Earth’s rotation caused by interactions between the atmosphere, oceans, and solid Earth, and are critical for precise timekeeping and geodetic applications.

More Info: https://geodesy.science/item/earth-orientation-parameter