Earth with perfect atmospheric propertiesThe atmosphere of the earth holds the most appropriate gasses in the most appropriate ratio needed for the survival not only of human beings, but also of all the living beings on the earth.Water – The mainstay of life
Thank goodness for the atmosphere, it keeps us warm! Without it, Earth would be a lifeless ball of ice with an average temperature of minus 60 degree Fahrenheit. In addition, the atmosphere absorbs or deflects incoming swarms of cosmic rays, charged particles, ultraviolet rays and the like. Altogether the gaseous paddling of the atmosphere is equivalent to a fifteen foot thickness of protective concrete and without it these invisible visitors from space would slice through us like tiny daggers. Even rainfall would pound us senseless if it were not for the atmosphere’s slowing drag. The most striking thing about our atmosphere is that there isn’t very much of it. It extends upwards for about 120 miles, which might seem reasonably bounteous when viewed from ground level, but if you shrank the Earth to the size of a standard desktop globe it would only be about the thickness of couple of coats of varnish!
Our planet is dominated by water and life, as we know it, depends upon water. Water is a good solvent that can dissolve a wide range of substances, an efficient thermal conductor, has remarkable surface tension and very importantly, water expands on freezing into ice, and the ice floats on top of the water! If ice sank when it froze, the way solids “ought” to when freezing out from the liquid form of the same substance, then in the winter ice would settle at the bottom of lakes and oceans and not on the surface. The water would lose energy and eventually ice would build up to freeze everything and there would be no marine life. But ice floats, and forms a protective cover, keeping warm the water below, stopping evaporation, and serving as an insulator. From his various studies of water and other substances, Henderson concluded “The biologist may now rightly regard the universe in its very essence as biocentric.”