Global Climate Change 101

Global Climate Change 101Greenhouse gases are naturally occurring compounds that trap heat in the earth's atmosphere and keep the planet warm enough for life to flourish. Since the mid 1800s, industrial practices driven by the burning of fossil fuels like coal, oil, and natural gas for energy have added unprecedented amounts of anthropogenic greenhouse gases to the atmospheric mix.

The primary greenhouse gas released during energy production is carbon dioxide (CO2), the atmospheric concentration of which has increased by 31 percent since pre-industrial times.1 As the concentration of CO2 grows and less heat is allowed to escape into space, the earth's atmosphere warms. During the 20th century, the earth's average surface temperature increased by 0.6 ± 0.2 degrees Celsius (about 1 degree Fahrenheit), and temperatures are expected to rise another 1.4 to 5.8 degrees Celsius (2.5-10 degrees Fahrenheit) by 2100.2 The increase in average surface temperatures has come to be known as global warming.

While the average surface temperatures on Earth are increasing, local and regional environmental conditions are changing in different ways and at different rates. The poles, for example, are expected to experience greater relative temperature increases and related changes than the tropics.3 The term global climate change refers to these changes in temperature and the host of related factors, including precipitation, humidity, sunshine, wind and weather events like storms, frosts, tornados, hurricanes and fogs.

Evidence for global warming and climate change include glacier retreat, sea ice melting, reduced snow cover and higher sea levels.4 Some plant and animal species are shifting their ranges toward the poles and to higher elevations while others are decreasing in number.5 The world has seen more severe weather events as characterized by El Nino and the increased frequency of "century-scale" storms during the last five years.6

Due to a lack of resources, poorer countries and communities will be less able to adapt to the challenges posed by global climate change and will therefore feel the consequences most acutely.7 In the United States, higher temperatures, sea-level increases and the increased incidence of droughts, severe weather events and the spread of disease-carrying species into new areas threaten:

  • human health and safety;
  • buildings, roads and other structures in low-lying and permafrost areas;
  • drinking and irrigation water supplies;
  • ecosystems;
  • air and water quality.8

A study produced for the U.S. Department of Defense states that an abrupt change in climate change, as has been predicted by some scientists, could "de-stabilize the geo-political environment, leading to skirmishes, battles, and even war" as a result of the following:

  • food shortages from decreased global agricultural production
  • decreased availability and quality of fresh water in key regions due to shifted precipitation patterns, which would cause more frequent floods and droughts
  • disrupted access to energy supplies due to extensive sea ice and storminess9

What Must We Do?

Humanity must make a rapid transition away from using fossil fuels (coal, oil, natural gas, etc). This can be done by using less of these fuels and switching to renewable and non-polluting energy sources.