Earth’s Water (Posted By Gary Cutrer)
Been a while since I thought about Earth’s water cycle — seem’s like it was about the fifth grade. Lately, though, I’ve been thinking about water as part of our atmosphere. Did you know that water vapor in the atmosphere is considered a “greenhouse gas?”
The Earth is pretty much a “closed system,” like a terrarium. That means that the Earth neither, as a whole, gains nor loses much matter, including water. Although some matter, such as meteors from outer space, are captured by Earth, very little of Earth’s substances escape into outer space. This is certainly true about water. This means that the same water that existed on Earth millions of years ago is still here.
Now, the USGS lesson states that not much water is being created or destroyed, but I beg to differ. The chemical breakdown of water and its “reassembly” is happening constantly and in great volume. The chemical breakdown of water occurs in growing plant life and animal life. The reassembly occurs when very old and not so old hydrocarbon compounds combust or burn. And, of course those hydrocarbon compounds are the products of once-living plant and animal life, both land- and ocean-based.
Disclaimer: I am not a scientist and have no idea what I am talking about but like to pretend I do.