The Greenhouse Effect
To understand the nature of the greenhouse effect on climate change which leads to global warming, we must first know what the greenhouse effect is.
When you enter a car that has been in the sun for quite some time, what is the first thing you notice? It is a lot hotter inside than it is outside. The sun’s rays (UV radiation, thermal radiation, visible light) enter the car through the glass panes and all the rays entering the car do not leave owing to the buildup of gases inside the car and the refractive properties of the glass itself. The weaker thermal radiation does not completely leave the car. This eventually heats up the inside of the car.
The same thing happens in a greenhouse. The plants in a greenhouse require a warm temperature to grow. Have you ever seen a greenhouse? It is made almost entirely out of glass. The heat is retained and the plants thrive. The temperature inside a greenhouse is always higher than the temperature outside.
This is called the greenhouse effect. What happens when the greenhouse effect occurs on a large scale in the world itself? This is where greenhouse gases come in.
Let’s have little back-story here. Other planets in our solar system are either extremely cold or really hot. It’s only planet earth that has climate which is mild enough to support life. This is because of the presence of a thin layer of naturally occurring greenhouse gases like carbon dioxide, methane gas, water vapor and nitrous oxide. These gases are part of our atmosphere. The atmosphere here plays the role of the glass pane like in the greenhouse. They let the sun’s rays inside but not all of it is reflected back. The greenhouse gases even facilitate the absorption of the heat thereby warming up the earth and not letting it become extremely cold like it otherwise should have been.
Since the beginning of the 18th century, the concentration of these gases in the atmosphere has started rising gradually. Since then, CO2 level have risen around 40%. And why is this happening? Different human activities, mainly industrial, have led to the production of these gases; the most common being carbon dioxide. The unnatural presence of increased greenhouse gases have led to a more pronounced greenhouse effect which has altered the temperature of the earth, leading to a phenomenon termed ‘Global Warming’.
Climate Change – Global Warming
A universal consensus of climate scientists is that there has definitely been a rise in the global temperature over the past century. The phenomenon of Global Warming if continued unchecked will have profound implications.
One of the main effects of global warming will be the rise in sea and ocean levels. Currently this is already occurring around us. Melting of glaciers and polar ice caps will contribute to the rise in water levels all over the world. Apart from this, fresh water sources will also reduce. According to scientific bodies like NASA, other consequences of global warming are ocean acidification, extreme weather events and other natural and societal impacts.
So can we control or check this from happening? There are some like Josef Werne, an associate professor at the department of geology & planetary science at the University of Pittsburgh, who believes that we have already crossed the point of no return. All we can do now is to adapt to the changing environment and the rising sea and ocean levels. We can still lessen the severity of climate change by aggressively enforcing policies that require different bodies to lessen CO2 levels in the atmosphere. Still others are even more optimistic believing that strong international agreements and actions can save the planet and its changing atmosphere.