Monday 3rd May, 2021
Science
The Greenhouse Effect and Global Warming
The earth is wrapped in a blanket of air called the ‘atmosphere’. It is made up of
several layers of gases such as: carbon dioxide, methane, water vapour, oxides of
nitrogen and ozone.
The Sun is much hotter than the Earth and it gives off rays of light energy. This
light energy travels through space and the atmosphere and reaches the Earth’s
surface. The rays of the sun warm the Earth’s lands and waters. The heat is reemitted and travels back into the atmosphere.
Specific gases in the atmosphere prevent some of the heat from escaping into
space and send it back to the surface. The atmosphere is made up of several
natural gases, some of which are in tiny amounts. These gases can trap the energy
from the sun and the heat given out by the Earth in the atmosphere.
The Earth’s temperature remains steady in there is a balance of these gases in the
atmosphere. These important gases are called greenhouse gases.
This natural process among the sun, the atmosphere and the earth is called the
Greenhouse Effect. The greenhouse effect is the warming of the earth because of
trapped energy.
The windows of a greenhouse play the same role as the gases in the atmosphere.
It keeps some of the heat inside the greenhouse, in the same way, some of the
energy remains trapped in the atmosphere to keep it comfortable for life.
Human beings and all other animals breathe out carbon dioxide which is the main
greenhouse gas. It is also produced in large quantities through human activities
when the trees and fossil fuel such as coal, gas and oil are burnt.
Green plants absorb carbon dioxide and produce oxygen during photosynthesis.
However, plants cannot filter the carbon dioxide quickly because of the large
quantities being produced. Thus, the amount of carbon dioxide in the air is slowly
but steadily increasing. This increase means there are more greenhouse gases in
the atmosphere to trap more heat.
Most scientists agree that man’s activities are making the natural greenhouse
effect stronger. If we keep on polluting the atmosphere with greenhouse gases, it
will have a very serious effect on the earth and all the creatures that inhabit it.
The enhanced greenhouse effect is sometimes referred to as climate change or
global warming. Since the Industrial Revolution, humans have released increasing
amounts of carbon dioxide and other greenhouse gases into the atmosphere over
a shorter period of time. Daily gas emissions have created a large imbalance
making a stronger, more enhanced greenhouse effect. This extra heat is causing
global warming, which in turn, is affecting the earth’s weather patterns.
A warmer earth may lead to changes in climate, a rise in sea level due to the
expansion of sea water and the melting of solar ice caps. A wide range of impacts
on plants, wildlife and humans are expected in future years.