In an essay published in the Winter 2012-2013 issue of Edible Wasatch I attempt to outline the most fundamental of Nature's phenomena, processes, and emergent properties that support life on Earth. What follows are two paragraphs from that essay that explain one of the three phenomena.
"The first is sunlight. It warms the Earth, evaporates water, causes winds, and powers, directly or indirectly, almost all of us Earth organisms. This energy is free, reliable, and reasonably well-distributed over most of the planet's surface. Solar power defined our development as a species. And despite our obsession with all sorts of things to burn, react or blow up for bursts of energy (to provide speed, convenience, comfort, or thrills), sunlight still makes up about 99% of all of the energy that flows through the Earth's natural and human-built systems. Nature's model for sustainability is sunshine-- the same sunshine that spills from the sky over the garden, even in winter."
"With respect to energy in general, and solar radiation in particular, the Earth is an open system. Energy flows. On balance, all of the energy flowing into the Earth-atmosphere system must rather quickly be re-radiated into space, or else the Earth's temperature will increase. For stability, 'energy in' must equal 'energy out.' If we impede the flow of heat energy away from the Earth (by enhancing the atmosphere's 'greenhouse effect'), then some of the re-radiated energy (heat) is retained, and the planet warms. If you've ever been in a closed greenhouse on a summer's day, you know what I'm talking about. Nature's model with respect to a greenhouse or to the Earth: maintain the normal energy flow to maintain the normal temperature. And in most cases-- especially where organisms or societies are adapted to 'normal,' normal is better than abnormal."
Read the entire essay at www.edibleWasatch.com