In the past 100 years, the Earth’s temperature has increased by 0.74degC (about 1.8F).
Global warming is caused by the release of carbon dioxide and other greenhouse gases by humans. The warming is accompanied by changes in weather patterns, such as a rise in the frequency and severity of extreme weather conditions.
Climate Change – A Natural Process
Many natural systems on continents and in oceans depend on a stable climate for survival. These include the weather, food production, freshwater supply, sea level, wildlife, and human health.
These processes are dependent on the stability of the atmosphere, which holds a number of naturally occurring gases, including water vapor, carbon dioxide, oxygen, methane, and nitrous oxide. Greenhouse gasses like CO2 and methane trap heat inside the Earth’s atmosphere, which makes the planet warmer than it would otherwise be.
The concentration of greenhouse gasses in the atmosphere has been rising steadily since the beginning of the Industrial Revolution. The increase is due to the burning of fossil fuels, which contain a lot of carbon – the stuff that was trapped beneath the earth’s surface for millions of years.
Burning these fuels, such as coal, oil and natural gas, releases carbon into the air in the form of carbon dioxide, a highly efficient gas that traps and radiates heat. This is why a small amount of CO2 can warm the entire planet.
In addition, the increasing amount of CO2 in the atmosphere is also causing the oceans to absorb more of it. This is why the oceans are getting warmer, and this has the potential to affect all life on the planet.
Arctic Ice Cap and Permafrost melting
This summer the floating north-polar ice cap reached its smallest size in recorded history, opening up a clear-water channel around the Northern Hemisphere to the Pacific. The same thing is happening with the Arctic permafrost, which was previously frozen in place for tens of thousands of years and now is melting.
The melting of the ice caps and permafrost will cause a number of problems for the Arctic ecosystem and human communities living there. As the ground melts, roads will slide and buildings will shift.
More forest fires will also be more common as the climate gets warmer. This will damage the forest and make it easier for invasive species, such as insects, to spread.
As the temperature and weather change, the geographic ranges of insects, plants and animals will shrink. This will lead to extinction of many species, especially those that need certain types of habitat.
Fortunately, there are ways to slow or even reverse the warming effects of climate change. One way is to give up our use of coal, oil and natural gas.
Another is to reduce the emissions of methane from the oil and gas industry, known as “fracking.” Reducing these emissions is a relatively cheap, easy, and effective way to begin addressing climate change.
The IPCC has estimated that by 2100, the average global temperature could reach 3degC above pre-Industrial levels if we don’t curb greenhouse gas emissions. This would lead to a significant reduction in life expectancy, increased disease, and loss of economic resources.