What is Climate Change?
Climate change is the major changes in temperature, precipitation, wind patterns, etc, that occur over several decades or longer.
It’s important to understand the difference between Climate and Weather
- Weather – refers to the local condition at any given time.
December 18th in Champaign was a high of 8oF with a low of -2oF with 0.1″ of ice precipitation. - Climate – refers to the long-term average from seasonal out to centuries and millennia.
Over the past 120 years, precipitation and average temperature for December
have increased in Champaign.
Facts:
- The average temperature on Earth has risen 1.5oF in the past 100 years.
- 97% of climate scientists attribute this to human activity.
- Temperature is projected to rise between 0.5o and 8.6oF in the next 100 years.
What effects have been observed?
- glaciers are retreating (melting faster than they reform)
- ice on rivers and lakes is breaking up earlier
- plant and animal ranges have shifted
- trees are flowering sooner
- sea levels have risen
- surface temperature has warmed
- ocean temperatures have warmed
- increase in frequency of intense rainfall events
- Increased pollen season
- Increased exposure to diseases carried by insects, arthropods, and rodents, such as lyme disease.
- Decrease in drinking water quality
- Decrease in air quality
- Property damage from flooding
In addition to impacts on the environment, some possible effects on human health include:
What evidence is there for climate change?
- Sea levels have risen 17cm in the past century
- Surface temperatures have risen even though solar output has declined
- Atmospheric carbon dioxide has increased
- The acidity of ocean water has increased by 30%
- Ocean temperatures have risen
- Greenland and Antarctica ice sheets have decreased
- Arctic Sea Ice has declined
Click to explore the evidence
What about the future?
At left CO2 emissions level off at about 550 parts per million (ppm) toward the end of the century, the average temperature of the continental U.S. would increase 4.5 degrees Fahrenheit by the year 2100. At right CO2 emissions rise to about 800 ppm (roughly double the 2013 level), temperatures would be, on average, 8 degrees Fahrenheit hotter than they were at the end of the 20th century. From NASA’s Goddard Space Flight Center
Based on scientific predictions:
- Temperatures will continue to rise
(National Climate Assessment). - Frost-free season (and growing season) will lengthen
(NASA Scientific Visualization Studio). - Changes in precipitation patterns
(National Climate Assessment). - More droughts and heat waves
(NASA Scientific Visualization Studio). - Hurricanes will become stronger and more intense.
- Sea level will rise 1-4 feet by 2100
(NASA Jet Propulsion Laboratory). - Arctic likely to become ice-free during summer
(Global Ice Viewer).