The water cycle is how water moves through the environment allowing the earth's ecosystem to function. It's a lot like your bloodstream in that sense: Carries things from one place to another, then starts over.
I don't know which step is considerd the 'start' since it's a cycle, but to paraphrase the Sparkletts Water exhibit from Sea World San Diego in the 70s:
The sea yields vapor to the sky
the sky returns it as rain
it flows down through forests and fertile plains
then it all begins again.
The sun warms the atmosphere, decreasing the vapor pressure, and causing water in the oceans (lakes, puddles, dog-bowls) to evaporate.
The moisture in the atmosphere, when cooled, condenses to form clouds which, in the right conditions, drop water in the form of rain (snow, sleet, hail) onto the ground.
The water (melted snow, sleet, hail) travels through brooks and streams to the ocean.
That example ignores the amount of water that is absorbed into the earth, taken up by the roots of plants (carrying vital nutrients, just like your blood), and is transpired out of the plants as vapor, which is just like the first step listed.
Vapor rises
Rain falls
water evaporates/transpires as vapor
repeat endlessly
Solon
I don't know which step is considerd the 'start' since it's a cycle, but to paraphrase the Sparkletts Water exhibit from Sea World San Diego in the 70s:
The sea yields vapor to the sky
the sky returns it as rain
it flows down through forests and fertile plains
then it all begins again.
The sun warms the atmosphere, decreasing the vapor pressure, and causing water in the oceans (lakes, puddles, dog-bowls) to evaporate.
The moisture in the atmosphere, when cooled, condenses to form clouds which, in the right conditions, drop water in the form of rain (snow, sleet, hail) onto the ground.
The water (melted snow, sleet, hail) travels through brooks and streams to the ocean.
That example ignores the amount of water that is absorbed into the earth, taken up by the roots of plants (carrying vital nutrients, just like your blood), and is transpired out of the plants as vapor, which is just like the first step listed.
Vapor rises
Rain falls
water evaporates/transpires as vapor
repeat endlessly
Solon