Global Warming and Greenhouse Effect

As we power our modern lives, some of the most disturbing changes are happening around us. Glaciers are melting, sea levels are rising, temperatures are soaring and wildlife population is dwindling day by day. The level of greenhouse gases is higher than at any time since the last 800,000 years. The result is global warming, although we are experiencing several other changes in the weather as well. The cumulative effect of the planet's weather changes is termed by scientists as 'climate change'.

Climate change encompasses not only rising temperatures but also other weather events such as extreme cold in some places, shifting wildlife populations, rising sea levels, etc. All of these changes continue to elevate as human acts continue to add greenhouse gases to the atmosphere.

Understanding the greenhouse effect

The greenhouse effect is the increase in temperature that caused certain gases to get trapped in the atmosphere of the Earth. These gases prevent the heat from escaping but let in the light - the same phenomenon that we experience in the greenhouse, hence the name.

Sunlight shines on the surface of the Earth, where energy gets soaked up and radiates back into the atmosphere in the form of heat. Greenhouse gases also accumulate some of the heat and rest releases back into space. As the number of greenhouse gases increases, more heat gets trapped in the Earth's atmosphere.

The greenhouse effect was discovered in 1824 by Joseph Fourier who calculated that Earth would be much colder without the presence of an atmosphere. This natural greenhouse effect makes the Earth's surface livable. In 1896, chemist Svante Arrhenius found that humans can increase the greenhouse effect by increasing the amount of carbon dioxide.

The amount of greenhouse gases has fluctuated in the past but has been almost constant for the last few thousand years. Although some human activities in recent years have disturbed the number of greenhouse gases and Earth's temperature as well. This can cause permanent damage to Earth's climate.

Some of the most common gases that contribute to greenhouse include:

• Water vapor: The most common greenhouse gas. As the temperature of the planet increases, so does the amount of water vapor and the possibility of clouds and precipitation. This makes the phenomenon one of the most important feedback mechanisms to the greenhouse effect.
• Carbon Dioxide: A very important component of the atmosphere that is released through respiration, volcanic eruptions but also through deforestation, burning fossil fuels, etc.
• Methane: This gas is released through the decomposition of wastes in landfills, rice cultivation, etc. It is a far more active gas than carbon dioxide to cause the greenhouse effect but also it is far less abundant.
• Nitrous Oxide: A greenhouse gas released by agricultural practices such as commercial and organic fertilizers, biomass burning, nitric acid production, and fossil fuel combustion.
• CFCs or chlorofluorocarbons: This is produced entirely due to industrial effects such as though refrigerators, air conditioners, etc. They are now largely regulated on an international level because of their ability to impair the ozone layer.

By: Kiara Sharma

School: Mahaveer Public School

Class: 10th