Climate change occurs when the Earth’s average temperature changes dramatically over time. As little as one or two degrees can be considered dramatic change because the Earth’s ecosystem depends on a very delicate balance, and even small shifts can have a far-reaching impact. A drop in average temperature can also be considered climate change, but in modern times people using the term are usually talking about global warming.
One reason that climate change has become a popular and, at times, controversial topic is that many people believe it is mostly the result of human activity. Burning fossil fuels, such as oil and coal, produces byproducts such as carbon dioxide gas. Since there are not enough plants on Earth to quickly transform all this emitted carbon dioxide into oxygen, the gas remains in the atmosphere. Through a process known as the greenhouse effect, the carbon dioxide traps solar heat, which leads to the warming of the planet.
Other causes of climate change that can be traced back to humans include deforestation, or the widespread cutting of trees, and methane gas production. Methane is typically produced in large amounts by mining, large scale livestock farms, rice paddies and landfills. The commercial use of fertilizers that give off nitrous oxide also contributes to pollutant levels.
Many people believe the effects of climate change can already be seen, in the melting of permafrost near the North Pole and the rise of sea levels. Rising ocean levels cause concern about shrinking coastlines and island land masses. A warmer climate can also cause more severe weather to occur, because weather phenomena, such as hurricanes, gain strength from hot, moist air.
Some say evidence of global warming can also be found in reduced wildlife populations. Some animal species, such as the polar bear, are slowly losing their icy habitats and have shown smaller populations over recent years. For this reason, many wildlife groups want the polar bear to be added to endangered species lists.
The concept of climate change is not a new one. The ice age of long ago is well documented and was another form of climate shift, one not brought on by humans. Modern climate shifts that are the result of human behavior may be positively affected by altering personal lifestyles. While some people consider global warming to be only a theory, it is becoming more widely accepted that the planet's climate is shifting and that people are not blameless.
Many simple lifestyle changes that people can make to help combat climate change center on conserving energy resources. Actions such as turning off unnecessary lights, buying used items rather than new ones and using public transportation or a bicycle instead of driving cars can make a difference. Recycling as many goods and materials as possible is another helpful way to conserve. If humans ignore climate change, it may continue to accelerate and drastically change the planet in both predicted and unforeseen ways.