| Author |
Message
|
| Quinta_Essentia |
 Posted: Sat Jul 12, 2008 5:11 pm Post subject: Is amount of water on earth a constant? |
 |
|
Forum Freshman
Joined: 12 Jul 2008
Posts: 1
Location: Madison
|
is there a constant amount of water on earth, generally speaking? is water being created in any significant amount by natural forces? is water being destroyed in any significant amount by natural forces? by destroyed i mean broken down into O and H.
_________________
Contrary to popular American opinion, the brain is not a vestigial organ |
|
| Back to top |
|
 |
| kevvy |
| Posted: Mon Jul 14, 2008 4:45 pm Post subject: |
|
|
Forum Freshman
Joined: 28 Apr 2008
Posts: 18
Location: Ireland
|
Evaporation and condensation are the greatest manipulators of water on the planet in terms of volume. As for the creation of water, innumerable natural processes produce it as a side reaction. It's pretty negligible as it is cancelled out by processes that "destroy" water.
A certain amount of water is "destroyed" by plants in the process of photosynthesis, where carbon dioxide and water are reacted to form glucose. I suppose you could include scientists carrying out electrolysis reactions too...
_________________
Dramatisation; may not have happened. |
|
| Back to top |
|
|
| Frenchi |
| Posted: Mon Jul 14, 2008 4:56 pm Post subject: |
|
|
Forum Sophomore
Joined: 06 Mar 2008
Posts: 129
Location: Port Saint Lucie, Florida
|
| I can't say for sure, but I think Quinta is referring to a more encompassing view of water on earth. While water itself will change forms quite often, its constituent particles will (in almost all cases that don't involve fission or fusion reactions) stay relatively constant. The only way we would lose hydrogen and oxygen molecules would be from nuclear reactions, or being brought into space (by astronauts, for example). |
|
| Back to top |
|
|
| CelticMadScientist |
| Posted: Mon Jul 14, 2008 11:51 pm Post subject: |
|
|
Forum Freshman
Joined: 12 Jul 2008
Posts: 19
Location: U.S.A.
|
I can throw out one idea - we do lose some atmosphere even with our magnetic field. And in the coming few centuries when it completes the polarity flip, we'll lose even more per time. I doubt it's very significant, I don't even know if water concentration is that high that far up.
_________________
Celtic Mad Scientist
Celtic Mad Scientist's MetaCafe Channel - Science & Fun How-to Videos
celticmadscientist.com |
|
| Back to top |
|
|
| Ophiolite |
| Posted: Tue Jul 15, 2008 12:54 am Post subject: |
|
|
Forum Radioactive Isotope
Joined: 25 Jul 2005
Posts: 4564
Location: Scotland
|
Not exactly. At high altitudes a small amount of water is dissociated into hydrogen and oxygen by UV radiation. The hydrogen molecules have a typical range (Gaussian distribution) of velocities. A small number of these molecules are travelling faster than escape velocity and are lost to the Earth.
The total volume of water lost since the formation of the Earth is small in absolute terms. It has probably been more than exceeded by the water provided by the occassional impacting comet. After all, the majority of the water on the planet probably came from comets during the Late Heavy Bombardment Phase of planetary formation.
_________________
The Universe is not only weirder than we imagine it is weirder than we can imagine. J.B.S.Haldane. |
|
| Back to top |
|
|
| Frenchi |
| Posted: Tue Jul 15, 2008 4:59 am Post subject: |
|
|
Forum Sophomore
Joined: 06 Mar 2008
Posts: 129
Location: Port Saint Lucie, Florida
|
Ah, my mistake, thanks for the correction  |
|
| Back to top |
|
|
| Old Fool |
| Posted: Tue Jul 15, 2008 3:23 pm Post subject: |
|
|
Forum Freshman
Joined: 17 Jul 2007
Posts: 67
Location: England
|
My interpretation of Quinta's question is:- is the amount of water (not hydrogen or oxygen) constant? (If I am wrong, it won't be the first time 
I can't see that it can be constant. We have all heard of the increase in carbon dioxide levels arising from combustion of fossil fuels, but when hydrocarbons are burnt, the products are not only carbon dioxide but water as well. If there is an increase in carbon dioxide as a result of burning oil and coal, there must surely be a parallel increase in the amount of water.
Water vapour also absorbs infra-red radiation and is probably classed as greenhouse gas.
(I'm not a chemist, so please regard my views accordingly) |
|
| Back to top |
|
|
| Bunbury |
| Posted: Tue Jul 15, 2008 7:24 pm Post subject: |
|
|
Forum Ph.D.
Joined: 26 Sep 2007
Posts: 743
|
| Old Fool wrote: |
| If there is an increase in carbon dioxide as a result of burning oil and coal, there must surely be a parallel increase in the amount of water. |
Right, but that water is really being returned to the atmosphere from whence it came millions of years ago. Over a very long time span perhaps the water is roughly constant? |
|
| Back to top |
|
|
|
|
