Rain Drops Keep Falling on My Head
by | Bert Thompson Ph.D. |
Imagine looking up and seeing 40 trillion gallons of water above your head. Now, since each one of those gallons weighs roughly 8 pounds, it would take one super-deluxe titanium umbrella to keep you dry under those conditions. Actually, the atmosphere above you contains over 40 trillion gallons—but, fortunately, it is not all in the form of liquid rain. God made water unique, in that it is the only natural substance that can be found in all three states (solid, liquid, and gas) at normal temperatures here on the Earth. This allows a great amount of the water to be suspended in our atmosphere as water vapor, while every single day approximately 4 trillion gallons fall to the Earth in the form of rain.
While pure water may be colorless, tasteless, and odorless, it does have some hidden qualities that make it extremely interesting. In fact, water's freezing and boiling points are the standards by which temperature is measured! On the Celsius scale, 0° is the point at which water freezes, while water boils at 100°. If you've ever put a canned soda in the freezer and forgotten about it, you are probably already aware of one of water's unique features—the fact that it expands when it freezes. Interestingly, when water is in its solid form (ice), it actually is less dense than when it is in its liquid form. It forms a hexagonal (six-sided) lattice as the molecules freeze. That is why ice floats to the top of your glass when you are gulping down your favorite drink. Consider for just a moment how much confusion there would be if ice sank. It is very likely that ice-skating would never have been invented; lakes would take forever to freeze from the bottom up; the polar ice caps would not be as large as they are, and all the sea ice would be at the bottom of the ocean. I also would venture to say that polar bears would have a hard time finding a home, and penguins would be packing their bags to move to Sea World. On the other hand, if there were no icebergs, the Titanic probably never would have sunk.