Part II– How does Climate Change Affect the World?
Provided by the Fort Independence Environmental Climate Change Working Group
Chair: Dennis Mattinson
1. How can a change of one or two degrees in global average temperatures have an impact on our lives?
Changing the average global temperature by even a degree or two can lead to serious consequences around the globe. For about every 2°F of warming, we can expect to see:
5—15% reductions in the yields of crops as currently grown
3—10% increases in the amount of rain falling during the heaviest precipitation events, which can increase flooding risks
5—10% decreases in stream flow in some river basins, including the Arkansas and the Rio Grande
200%—400% increases in the area burned by wildfire in parts of the western United States 
Global average temperatures have increased more than 1.4 degrees Fahrenheit over the last 100 years.  Many of the extreme precipitation and heat events that we have seen in recent years are consistent with what we would expect given this amount of warming.  Scientists project that Earth’s average temperatures will rise between 2 and 12 degrees Fahrenheit by 2100. 
2. Do emissions of carbon dioxide from human activities have a big impact on Earth’s climate?
Plants, oceans, and soils release and absorb large quantities of carbon dioxide as a part of the Earth’s natural carbon cycle. These natural emissions and absorptions of carbon dioxide on average balance out over time. However, the carbon dioxide from human activities is not part of this natural balance. Ice core measurements reveal that carbon dioxide levels in the atmosphere are higher than they have been for at least 800,000 years.  The global warming that has been observed in recent decades was caused by elevated levels of carbon dioxide and other greenhouse gases in the atmosphere, due primarily to human activities. 
3. Will a small rise in sea level affect people (even in the United States)?
A small rise in sea level will affect many people, even in the United States. The amount of sea level rise expected to occur as a result of climate change will increase the risk of coastal flooding for millions to hundreds of millions of people around the world, many of whom would have to permanently leave their homes.  Global sea level has risen approximately 9 inches, on average, in the last 140 years.  This has already put some coastal homes, beaches, roads, bridges, and wildlife at risk.  By the year 2100, sea level is expected to rise another 1.5 to 3 feet.  Rising seas will make coastal storms and the associated storm surges more frequent and destructive. For example, in New York City what is currently termed a once-in-a-century coastal flooding event could occur as frequently as once per decade. 
- NRC (2011). America’s Climate Choices: Final Report. National Research Council. The National Academies Press, Washington, DC, USA.
- NRC (2010). Advancing the Science of Climate Change. National Research Council. The National Academies Press, Washington, DC, USA.
- NOAA (2011). 2010 Tied For Warmest Year on Record. National Oceanic and Atmospheric Administration. Accessed 3/16/2012.
- EPA (2010). Climate Change Indicators in the United States. U.S. Environmental Protection Agency, Washington, DC, USA.
- USGCRP (2009). Global Climate Change Impacts in the United States. Thomas R. Karl, Jerry M. Melillo, and Thomas C. Peterson (eds.). United States Global Change Research Program. Cambridge University Press, New York, NY, USA.
- NRC (2011). Climate Stabilization Targets: Emissions, Concentrations, and Impacts over Decades to Millennia. National Research Council. The National Academies Press, Washington, DC, USA.
- IPCC (2007). Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Pachauri, R.K. and A. Reisinger (eds.)]. Geneva, Switzerland.
4. What are the effects of Climate Change on world life?
Life on Earth is profoundly affected by the planet’s climate. Animals, plants, and other living beings around the globe are moving, adapting, and, in some cases, dying as a direct or indirect result of environmental shifts associated with our changing climate—disrupting intricate interactions among Earth’s species, with profound implications for the natural systems on which humans depend. Climate change is happening on a global scale, but the ecological impacts are often local. – (COMMITTEE ON ECOLOGICAL IMPACTS OF CLIMATE CHANGE)-