Global Warming: An Introduction

The Earth is getting progressively warmer. But exactly what is global warming?

How Does Global Warming Occur?

The Earth maintains a balance of heat: in the daytime: heat from the sun warms the planet, while at night this heat is emitted back out of the Earth's atmosphere. But if greenhouse gases like CO2 increase, heat is trapped and the Earth's surface temperature rises. This is the global warming phenomenon.

Why is Global Warming a Problem?

Melting of the polar ice will cause sea levels to rise. This will submerge the coasts of some countries and regions. If there are large changes in temperature due to global warming, the result will be catastrophic droughts and desertification, and localized torrential rain. These in turn will affect living things and food production, and cause endemic diseases.

The Future of Our Planet

The IPCC's Fourth Assessment Report predicts a number of serious affects from global warming.

If measures are not taken, scientists predict that by 2100, temperatures will rise by as much as 6.4° C, sea levels will rise by up to 59 centimeters, and glacial and polar ice will melt. Besides the chance of late summer ice in the North Sea completely disappearing by the middle of this century, scientists also predict that extreme weather will cause more frequent occurrences of heat waves and rainstorms, and that rising sea levels in the tropics will be accompanied by stronger tropical cyclones, causing more gale force winds and heavy rains.

Why are Greenhouse Gases Generated?

CO2 constitutes the largest greenhouse gas emissions. Before the industrial revolution (which started in the late 19th century), the only CO2 emitted was from the breathing of humans and animals as part of the natural circulation loop. But CO2 emissions from human activities have been steadily rising since the industrial revolution and with the increase in the use of fossil fuels (coal, oil).