From the National Park Service Climate Friendly Parks website:
Climate change refers to changes in the Earth's long-term weather patterns. Some changes in climate occur naturally; gradual temperature fluctuations over thousands of years are a natural part of the Earth's climate. The Ice Age, for example, was a period of time when our climate was much cooler than it is now. However, human activities can also cause changes; the term "climate change" is generally used to describe a more rapid, human-caused increase in the Earth's average temperature.
Scientists believe that humans are increasing the greenhouse effect through activities that produce greenhouse gases (GHGs). Since the beginning of the industrial revolution, atmospheric concentrations of carbon dioxide have increased over 35 percent, methane concentrations have more than doubled, and nitrous oxide concentrations have risen by about 18 percent. The increase in global temperatures associated with increased atmospheric concentrations of these GHGs is commonly referred to as global warming, which is manifested locally or regionally as climate change.
How do we affect climate change?
Check out the to see how our choices at home can reduce carbon dioxide emissions.