The recent tsunami that ravaged northern Japan makes me think about the power of water and how much we depend on it.
We are in fact living in a water world because the earth is 75% covered with water. Our body consists about the same percentage of water, too. We can live without food for months, but not without water for days.
Water does not exist in the oceans only. The continent of Antarctica, the North Pole, Greenland, and a large part of Siberia hold tremendous amounts of water in the form of ice and permafrost. Should the whole of Greenland melt, which is slowly occurring now due to global warming, the ocean level would rise by an estimated 10 feet or more. What would happen to all the big coastal cities of the world?
The salty water of the ocean sustains countless species of fish for human consumption. This is where food is harvested in the wild. In contrast, most of the food produced on land are cultivated such as grains, rice, vegetables and fruits; and industrially produced such as beef, pork and chicken. The ocean is in fact the last wild frontier.
Two great benefits of the ocean are usually taken for granted. The first is its moderating effects on the climate overland. Inland regions have more harsh climates the farther they are from the coast. The second benefit is the ocean acting as a huge garbage dump. All sewage, either treated or not, are dumped into the oceans. In cases where it is dumped into rivers and lakes, the sewage will reach the ocean eventually. Due to its huge size, salty nature, and microorganism inhabitants, the ocean effectively disinfects human wastes dumped into it. It can regenerate itself and continue with its work unless being overly polluted.
Where does rain come from? The sun is our virtual desalination plant. The sun’s heat evaporates water to form clouds of vapor over the ocean. The clouds are then carried by wind inland and released as rain or snow. This replenishes rivers, lakes, and underground water so important for irrigation and other human purposes.
History tells us that great civilizations developed along the banks of major rivers such as the Nile and Huang He. How countries developed also depended on their efforts in water management such as building dams, canals, aqueduct, irrigation projects, and so on. For instance, the big city of Los Angeles is sustained with water pumped from the Colorado river, and the snow melts from the Sierra mountains along the eastern border of California. The success of Great Britain in colonizing the world in the 19th century was due to the power of the Royal Navy, which became mechanized after the invention of the steam engine. What is the steam engine? It’s just a form of water technology.
Some writers suggest that water is the new oil of the future. This is very true indeed. Oil is gradually being substituted by renewable energy such as solar, wind, hydro, and nuclear. Water cannot be substituted and is required for human life.
On the surface, there appears to be plenty of water around. However, most of it is salty ocean water. Human survival depends on the climate that brings rain or snow to the places where water is needed. It’s not how much water we have in the ocean but how much water the climate system brings from the ocean. Should the climate change dramatically, whether or not due to humans burning too much fossil fuels, we might not get enough precipitation at the places in need. As a consequence, famines and wars would follow. Cities would wither away.
What about water desalination? Currently, the cost of generating water from the ocean is still high compared with obtaining it from rivers and underground. Even when the cost is brought down, there remains the additional cost of transportation from the coast to inland areas. The best alternative right now is to protect the environment and the climate, so as not to hinder nature’s job of sustaining life on land with rain and snow.