Sunday, February 5, 2012

Earth -- A Water World

Some of the most familiar and plentiful things in our experience are also some of the most underappreciated. Water falls into that category. The surface of Planet Earth is 70% water covered to an average depth of about two miles. Earth’s oceans contain 97% of Earth’s water. Life on earth depends on this water in manifold ways. To the average person most of these ways are unknown and undervalued. If I were still a teacher beginning a unit on water, I might introduce the topic by using the catchy idiom “Water rules.” When we discover deeper truth about some of the most mundane matters or events, our expectations are often exceeded. Water provides a superb example.

Earth was a water world in the early days of earth’s formation. Genesis 1:6-8 describes events of Day 2. Reference to the expanse in the midst of the waters separating the waters from the waters, probably relates to the dividing boundary between the oceans and the atmosphere. In the water cycle liquid water evaporates from oceans and lakes into water vapor and later falls as a variety of precipitation. This is described in detail in the creation account of Job 38. Water must not merely be present on earth to sustain life. It must also be cycled and recycled endlessly through the ages because there is a finite supply of water on earth. The recycling of water (the water cycle) is a vital feature of God’s plan for the successful operation of this planet.

Bible passages referring to the “expanse” are used along with the terms “dome,” or “canopy.” Meteorologically, all of earth’s weather occurs in the troposphere, the thick lower layer of atmosphere supplied with water vapor mainly from the oceans. The boundary between the troposphere and thin upper atmospheric layers is quite distinct. The troposphere is the zone where earth’s weather occurs. Evaporation supplies this zone with water vapor to sustain the water cycle. The water cycle operated beginning with the second creation day. Vegetation, with “plants yielding seed, and fruit trees bearing fruit” was the sequel on Day 3.

Skeptics like to claim these Genesis 1 descriptions echo the primitive pagan mythologies of nations surrounding Israel. One such image occurring in Job 37:18 refers to the sky as “hard as a mirror of cast bronze.” A few verses later, however, the sun is described as “bright as it is in the skies after the wind has swept them clean.” The brightness of the sky is compared to the brightness of a highly polished cast bronze mirror. Scripture writers used figurative language to augment their point poetically. Much of the imagery occurring in Job 38 clarifies the writer’s understanding of the many varied water cycle phenomena occurring in earth’s atmosphere.

Historical geologists have described how earth became a “water world” very early in its history. Before the water cycle was established numerous interrelated events occurred on our planet. It is certain that modern life would be impossible had the water cycle not been established. Ancient giant rainstorms bathed the earth in liquid water. Plentiful bacterial life of various types then appeared as precursors of today’s mineral resources and producers of the life sustaining atmosphere we enjoy today.

Modern man is consuming the resources formed over billions of years at an alarming rate. On the upside, many humans are learning to use water, mineral, and food resources more wisely as time progresses. We are also learning to recycle, an idea that originated in the mind of God. Some people, even in our churches, are ignorant of past earth processes which brought our modern treasure trove of mineral, energy, and food resources into existence. Better understanding of these processes should be an important product of church educational programs. In turn, responsible stewardship of nature should be the outcome.