Climate Change & The Data
Climate Change Primer
Certain atmospheric gases are central to the climate change debate and six are currently accepted as contributing to what is known as the “Greenhouse Effect.” These greenhouse gases – GHG in most reports – are linked to the current global trend toward warming temperatures. The stand-out among these gases is carbon dioxide, or CO2. The influence of carbon dioxide is so high that it has become the standard used to measure the other greenhouse gases.
As visible light from the sun passes through the atmosphere, it is absorbed by the Earth’s surface. Some of that energy is then emitted back to the atmosphere as heat. Greenhouse gases and water vapor absorb much of that heat, which would otherwise be released into space. The temperature of the atmosphere is raised and, subsequently, the temperatures on the Earth’s surface. This greenhouse effect is necessary for the planet to be livable.
Carbon dioxide – the main greenhouse gas – also cycles naturally between the atmosphere and living organisms. Plants and algae remove carbon dioxide from the atmosphere through photosynthesis, while all living things release carbon dioxide via respiration (i.e., breathing). Carbon dioxide also cycles back and forth between water on the Earth’s surface (freshwater and the oceans) and the atmosphere. But in addition to this natural carbon cycling process, humans release large quantities of CO2 into the atmosphere by burning fossil fuels, deforestation, land uses, and industrial processes. The resulting measurable increase of carbon dioxide and other greenhouse gases is linked to rising global temperatures.
