Every Day Is Special: March 22, 2013

March 22, 2013 - World Water Day

What could be more crucial to the quality of life than plenty of clean water?

We humans use water to drink, to cook, to wash up and clean things, to keep our crops and livestock and gardens and pets alive, to make products, to play, and even as a source of natural beauty. And in several of these uses, not just any water will do – it's got to be fresh (not salty), unpolluted, drinkable water!

(Another word for water that is safe to drink is potable.)

A young woman named Megha Kumar won a contest for this year's Water Day slogan: “Water, water everywhere, only if we share.”

Although about 70% of the Earth is covered by water, most of it is salty ocean water. As a matter of fact, 96.5% of Earth's water is in its oceans! Some of the rest of Earth's water is tied up in glaciers and icecaps, some is deep down in the ground, and some is vapor high in the sky. A tiny percent of Earth's water is fresh water in rivers, lakes, reservoirs, and aquifers.

Of course, water isn't just sitting still. Everyone knows about the water cycle: water evaporates from the ocean (and every other water source) and as vapor becomes part of the atmosphere; then the vapor condenses back into liquid or freezes into ice crystals; eventually it falls out of the sky as rain or snow or sleet or hail. It either packs up on the ground (as snow or ice), or it runs off of or seeps into the ground (as water). Some of the rainwater and snowmelt finds its way into rivers and lakes, and rivers eventually run into the ocean. Water, water everywhere—changing its state from liquid to vapor to frozen and back again to liquid—changing its location—sometimes picking up pesticides and industrial or sanitation waste, picking up minerals, eroding rocks, carrying soil.

And let us not forget that part of the water cycle is involves living things. Animals drink water, and plants soak up water with their roots; both animals and plants release water back into the environment in several ways.

Our human bodies are from 60 to 70% water, and some creatures are about 90% water (by weight). Here on Earth—and scientists suspect everywhere—life is dependent on water. Planetary scientists who hope to find some sort of life on other planets aren't just on the lookout for water, they're looking for liquid water. These scientists point out that the biochemical reactions that sustain life need fluid to occur, because molecules can dissolve into liquid, and substances can move from one place to another in a cell or body. Getting molecules where they need to go is too hard within a solid. And gas-based (vapor-based) life would go all to pieces because in a gas molecules move too much, too quickly.

Okay, so fresh, clean, liquid water is super important to all of us. It is unevenly distributed on Earth, and we can't count on the same amount throughout the year. What to do? That winning slogan I told you about gives one hint: we should share. If we all conserve water whenever we can and cooperate with each other to share water and to share technology to purify water, we will all be better off.