The Sun is central to rising temperatures and climate change being experienced in the world today. When heat from the Sun reaches the Earth, approximately 30 percent of it is reflected back into space by clouds, atmospheric particles, reflective ground surfaces, and ocean surf. The remaining 70 percent of the heat is absorbed by the land, air, and seas. As the land, air, and seas warm, they emit thermal radiation, or infrared heat. Some of this infrared heat travels directly out to space, allowing the Earth to cool while the rest is absorbed by greenhouse gases (such as water vapour, carbon dioxide and methane) which form a blanket over the Earth to trap some of this heat, preventing it from escaping into space. This process of greenhouse gases forming a blanket over the atmosphere to trap heat is what is known as the greenhouse effect.

When these greenhouse gases absorb the energy/heat radiating from the earth’s surface, microscopic water or greenhouse gas molecules turn into tiny heaters which radiate the heat in all directions, including back to the Earth. The energy that radiates back toward the Earth heats both the lower atmosphere and the surface, enhancing the heating they get from direct sunlight. On the whole, this re-absorption process is good. If there were no greenhouse gases or clouds in theatmosphere, the Earth’s average surface temperature would be a very chilly -18°C instead of the average of 15°C that it is today. The greater the amount of greenhouse gases in the atmosphere,
the greater the amount of heat the atmosphere can retain.

The natural greenhouse effect is both good and necessary for the preservation of life on earth. However, as more greenhouse gases build up in the atmosphere, more heat is trapped, causing the earth to warm faster than naturally intended. This is called the enhanced greenhouse effect. The
enhanced greenhouse effect leads to global warming, which drives the major effects of climate change like rising global temperatures, melting glaciers, heavier rainstorms, more frequent droughts, heat waves and floods etc.