Water+cycle+and+rivers



The water cycle has no starting point but we will begin at the ocean
 * sun heats water in oceans
 * some evaporates as vapour into air
 * rising air curents takes vapour into atmosphere
 * vapour rises into air where it cools which causes it to condence into clouds
 * air currents move clouds around globe which cause them to collide and grow
 * Precipitation (rain) then falls from the sky it can also fall as snow
 * most precipitation falls back into oceans or over land
 * precipitation flow over ground as surface runoff
 * bits of runoff enter rivers in vallys
 * runoff and ground-water accumulateand are stored as fresh water in lakes
 * much of runoff soaks into ground as infiltration
 * some ground water finds openings in the land surface and emerges as freshwater springs