There is extraordinary intelligence and design with regard to the ratio of land and water on earth. One-quarter of the earth’s surface is dry land, and three-quarters is covered with water. In the United States alone we have three and three-quarter million square miles of dry land, and all of it has to be watered and cared for. In fact, if it weren’t watered, there would be no vegetation and no growing grass or trees.
Just imagine for a moment that the ratio of land and water was changed from what it is at present. The proportion of water and land determines the rainfall on the earth. Suppose the ocean was only half its present size. That would mean our rainfall would only be one-quarter of what we now receive. What would that mean for the three and three-quarter million square miles of land we have in these United States? All of it would be turned into a vast, dry desert! But on the other hand, if half the present land were added to the ocean, there would be four times as much rainfall as there is now, and the entire United States would be turned into a vast marshland where human life would be almost impossible.
Now suppose that mankind had to water this entire three and three-quarter million square miles of land. How could we ever spread out that water and irrigate the land effectively? What a tremendous task that would be! “There’s plenty of water in the ocean,” someone might observe, “we could simply use it to water the dry land.” Although it may sound reasonable, there are three problems connected with it. First, transportation. We’d have to get the water out of the ocean and spread it evenly over the land. The second problem is the salt it contains, which would kill all the green plants. The third problem is weight. Water is 800 times the weight of the atmosphere, presenting the challenge of how to transport and disperse it.
How has Hashem solved the weight problem? First, He uses heat. We know heat expands things and cold contracts them, and that water is the material most subject to expansion. In fact, when turned into steam, it becomes 1,600 to 1,700 times its original volume. Remember, though, this water is 800 times heavier than the atmosphere. But Hashem simply sends down the warming rays of the sun, turning the water into a vapor that is 900 times lighter than water. Now it is one-eighth times lighter than the atmosphere. So this vapor is easily lifted up out of the ocean, carried into the sky—perhaps miles into the air—and formed into great cloud masses.
The second problem is the deadly salt in the saltwater, but Hashem simply evaporates the water and leaves all the mineral deposits and impurities behind. Taken up into the clouds, the water is sweet and soft, perfectly adapted to irrigate the earth.
What about the third problem—transportation? The water that is lifted up is still hanging over the ocean, which doesn’t need any more water. Hashem sends along winds to blow the clouds and spread them out over the dry land area where it is needed. But how to get all the water down out of the clouds? Here is another wonderful miracle. Cold will contract, of course, so when the clouds pass over the mountain peaks, the cold air reaches up and begins to cool those clouds, turning the vapor into a condensation of moisture.
Now consider what would happen if the clouds gave up all the water they contain at one time—it would flood the entire surface of the earth with three feet of water! Therefore, the cooling process must be gradual. For example, if the temperature of the cloud is lowered by 9 degrees, it will drop half its water! So Hashem arranges for a gradual cooling process to let the rain come down in gentle to vigorous showers to provide the amounts needed to revive the earth. What an incredible process! Of course, some of it rains back into the ocean, but it is needed there to provide the necessary amount of oxygen for fish living in salty ocean beds.