Understanding Global Warming

What is the greenhouse gas effect?

A greenhouse is a pichouse used to grow plants. It is made of glass, so that when the sunlight enters the in the house the heat is trapped inside, the glass walls do not allow the heat to escape.The same phenomenon occurs on the earth’s surface. When the sun’s ultraviolet radiation (UV rays) enters the earth’s atmosphere, roughly 31% is reflected back while 69% is absorbed by the earth’s surface. This absorption causes the earth’s surface to heat up during the day, and at night the absorbed heat is released back into the atmosphere, but is trapped by the greenhouse gases present in our atmosphere. This in essence is the greenhouse gas effect.

What are greenhouse gases?

The different greenhouse gases are water vapor, carbon dioxide, methane, nitrous oxide and ozone. The role of ozone is quite interesting and rather double edged, when ozone occurs in the higher levels of the stratosphere it absorbs the suns UV rays and does not allow it to enter the earth’s atmosphere. But when ozone occurs in the troposphere i.e. in the layer closet to the earth’s surface, it traps the suns UV rays and does not allow it to escape the earth’s atmosphere.


What is global Warming?

It refers to the graduated increase in the earth average temperatures as a result of the greenhouse gas effect.