Isochrones


Isochrones

 

isolines of the simultaneity of a particular phenomenon.

In meteorology, isochrones of various meteorological elements are examined (for example, a perennial average transition of air temperature through 0°C). In astronomy, isochrones of solar eclipses are constructed corresponding to the beginning or end of a partial eclipse or to the greatest phase. Isochrones of the beginning and end of a partial eclipse are contours of the lunar penumbra that graphically indicate its progress along the surface of the earth.