By Tito Sasaki
Whiskey is for drinking; water is for fighting over.” Mark Twain was right. When we talk about water, it is always against the background of who gets how much of it. When we fight over something, may it be for a territory or a girlfriend, we often neglect to appreciate the beauty of the object we are fighting for. While we are poised for the State Water Board’s counterattack on the court decision against the frost protection regulation, we might as well sip wine, or whiskey if you are a Twain devotee, and think of the unique physical beauty of water.
Water is unique in its density change to temperature. While other matters contract as temperature goes down, water does so only to a point: 4°C (39°F). Thereafter, it expands until it becomes ice. At that point it suddenly bulges, and the density drops by some 9%. Thus the water seeped into the fine fissures of rocks expands and contracts as temperature goes up and down, and eventually breaks rocks into soils. So, if your farm is blessed with fine soil, thank water for it.
More importantly, water being heaviest at 4°C, the bottom of a frozen lake always has 4°C water while colder water rises to form ice at the top. Without this abnormal trait of water, bodies of water would start freezing from the bottom up. Solar radiation won’t thaw the ice because of the absence of natural convection in such water. Most water would eventually become ice, and the oceans would no longer moderate global climate.
Another unique attribute of water is that it is an excellent solvent. We all use water to wash ourselves of dirt and grime (often aided by soap, which emulsifies hydrophobic substances such as oil and grease). Water also dissolves minerals and organic matter in the soil, and carries them to plants as nutrients.
How the dissolved nutrients are delivered to every part of a plant is up to another trait of water: high surface tension. Because of the four intermolecular hydrogen bonds for each water molecule, there are unusually strong attractive forces among the molecules, making water exhibit strong surface tension. This, in turn, enables water to lift itself up as capillary action against gravity. This is how the treetop gets water and nutrients from the ground tens of feet below.
Water also has exceptionally high latent heat. Latent heat refers to the heat released or absorbed when a matter goes through a phase transition between liquid and solid or liquid and gas. Water absorbs heat as it evaporates. This is why the body sweats to keep it from overheating. Conversely, heat is released when water becomes ice. This is why we overhead water the vines for frost protection. When ice forms around the bud, it releases heat and protects the bud from frost damage. Once ice is formed, it prevents further cooling inside by its anomalously low thermal conductivity.
All these are just the tip of the iceberg of the unique properties of water. With other unusual attributes, water turns out to be the only basic medium that can support life. Water is worth fighting for, particularly when we consider the fact that we need some 800 gallons of it to produce just enough food for one person’s daily dietary need.