A creep is a slow downward progression of rock and soil on a slope of terrain.
A rockfall is a mass of loose rocks that fall down a slope.
A landslide is a mass of earth and/or rocks that have collapsed from a mountain or cliff.
A mudflow is an avalanche of big amounts mud.
The psychrometer is a device used to measure the
Relative Humidity (RH) of the air.
Relative humidity is the ratio of
(the amount of moisture in the air, here and now)
to
(the amount of moisture the air could hold at this temperature) .
Being a ratio, it has no units. It's just a naked number, always
less than ' 1 ', and usually expressed as a percent.
