There is a lot of talk about "Global Warming" these days and it gets blamed for the obvious recent changes in the World's climate. Heavier rainstorms, more flooding, higher winds, higher temperatures, droughts, tidal waves - and so on. Global Warming itself gets mostly blamed on the release of chemicals into the air by industrialised nations, but that is not the whole picture. EVERY nation is to blame for the increasingly adverse weather effects of recent years because they are ALL cutting down trees unnecessarily. This upsets the delicate balance of the Earth's "Weather Engine", which is rapidly going out of control. Trees are vital to the operation of this extremely sensitive system.
"Killing" trees can kill animals and humans too. If you just consider the fact that a large mature tree in 24 hours reprocesses large amounts of carbon dioxide gas and then releases back into the atmosphere enough oxygen for 30 adult humans to breathe, the importance of trees is obvious. All animal life (ourselves included) breathes in oxygen and breathes out carbon dioxide. We upset this chemical equation to the peril of the entire planet. Trees left to grow undisturbed have longer life spans than humans. For example, a Beech tree can live 200 to 300 years, an Oak tree up to 500 years, a Yew tree up to 3000 years, a Californian Redwood up to 5000 years. When the continuous cutting down of trees reaches a critical point (and we don't know when that point will be reached), in theory it means that humans and animals will have no oxygen to breathe! The ancient peoples revered and worshipped trees, not just because trees were powerful and lived a long time, but for the advantages they gave to humankind.
As well as life-giving oxygen, trees provide vital shelter. They break the force of chilling winds, and provide shade from the sun's burning rays. Shade is growing ever more important as human activity causes holes to develop in the Earth's protective ozone layer in the upper atmosphere. Would YOU like it if you had to spend your entire life in buildings and vehicles, and could never venture out of doors onto the "fresh air"? Because that is just what will happen if there are no longer hedgerows, woods, forests or trees in the countryside and city parks. The moderntendency to think of treesa as being "just for decoration" is nonsense. True, the countryside would look very bare and bleak without trees and from an aesthetic point of view the tourist industry of most of the countries of the world would cease to exist if trees and hedges disappeared. But hedges are so much more than mere "landscape decoration".
A hedge with 40% permeability, that is, one which lets 40% of moving air filter through it and deflects the other 60%; is a far more efficient barrier to wind than a solid barrier, such as a wall or fence. Not only do solid barriers tend to break or blow down in high winds conditions, they themselves cause strong disturbances in the airflow at ground level, which can extendupwards todisturb the "surface wind". Meteorologists define the bottom 300 feet of the atmosphere as the region where "surface winds" occur. This is,of course, the region all animals and most humans inhabit. The bottom 30 feet of the atmosphere is an area where the main friction between moving air (wind) and the earth'ssurface is active, causing a "distirbed airflow" ofswirls,eddies and gusts.This is why meterological instruments to measure windspeed are always sited away from buildings and on poles which lift them above the 30-foot level. It isalso the reason why the sails of windmills were placed on high towers,and why modern wind-powered electricity generators have their vanes lifted even higher above the ground. This gets their sails or propeller blades into an area where they can turn more smoothly, reducing wear on their mechanisms and producing a more regulated power supply.
To view and learn more about trees and global warming please visit -
http://iol.ie/~plugin/trees.html
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