That’s a good question – tricky – I don’t think there is an accepted answer to this one – one theory that I’m familiar with is water-rich meteorites/asteroids bombarded the earth bringing water with them.
Hydrogen is the most abundant element in the universe and oxygen although far less abundant is very reactive so it’s not too surprising that icy asteroids formed and then that they bombarded the earth….
I believe it’s because we’ve been hit very many times by meteorites packed full of water. They were just sort of left here by them.
Water is a very simple molecule and hydrogen and oxygen are very reactive so it’s easy for them to combine.
Do you know in a 100-year period, a water molecule spends 98 years in the sea, 20 months as ice, about 2 weeks in lakes and rivers, and less than a week in the atmosphere. Cool, huh?
Oceans are amazing – they cover 70% of the Earth’s surface but contain 97% of all of the water on Earth!
The oceans and seas are the source of water vapour into the atmosphere to produce rain for freshwater, which eventually makes its way back into the sea. Not only that but the oceans also affect weather and climate.
The oceans also amazingly contain 50-80% of all life on Earth – absolutely amazing!
What an interesting question. I suppose there is sea, because such a large proportion of our planet (at least on the surface) is made up of water. But that just leads us to another question, why is there so much water?
Kl answers, thnx 4 replying so quickly! I find it intresdting seeing ur different views on the subject. BTW Tim- I think that would be a intresting question, but another would be is why do the tides come in and out, I find it all very intresting, why all these things are on the planet
Hi Peaches
Apparently tides occur because of the effects of gravity from both the moon and the sun, in addition to the Earth continually rotating. All of these effect when tides come in and out.
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peaches247 commented on :
Kl answers, thnx 4 replying so quickly! I find it intresdting seeing ur different views on the subject. BTW Tim- I think that would be a intresting question, but another would be is why do the tides come in and out, I find it all very intresting, why all these things are on the planet
Donna commented on :
Hi Peaches
Apparently tides occur because of the effects of gravity from both the moon and the sun, in addition to the Earth continually rotating. All of these effect when tides come in and out.
Jo commented on :
Good question peaches!
peaches247 commented on :
I think thats kl donna- I guess effects every thing else! Thnx both of you
Donna commented on :
you are welcome!