Climate change and the greenhouse effect

Humans have enhanced the greenhouse effect and are causing climate change. The greenhouse effect is the result of the interaction of the sun's energy with greenhouse gases in the Earth's atmosphere. Since the Industrial Revolution, the components within the Earth's atmosphere that keep the greenhouse effect constant are no longer in balance. The amount of greenhouse gases in the planet's atmosphere is the highest it has been in the last 3 million years.1 2 Humans have increased greenhouse gas levels which has enhanced the greenhouse effect to the point where too much heat is being trapped in the Earth's atmosphere. This excess heat creates global warming which affects the planet's weather patterns and leads to different climate changes around the world.3 4

Climate change and the greenhouse effect - How are they related?

The greenhouse effect has existed as a natural process for millions of years, and plays a critical role in regulating the overall temperature of the Earth. Without the greenhouse effect, the planet would not be warm enough for humanity, or indeed many forms of life, to survive.5 But over the last 100 years, the Earth's average temperature has risen by about 0.75° C.6 7 This is because the enhanced greenhouse effect has created a net increase in the amount of heat trapped in the planet's atmosphere.

This 0.75° C increase may seem very small but the the impacts associated with a 2° C increase of the average global temperature will result in extremely dangerous climate change. The Intergovernmental Panel on Climate Change (IPCC) has predicted that weather patterns will be significantly altered due to an increase in global warming of this size.3

Climate change is already causing:

• Greater strength of extreme weather events like: heatwaves, tropical cyclones, floods, and other major storms.8 9 10 11
• Increasing number and size of forest fires.12 13
• Rising sea levels (predicted to be as high as two feet by the end of the next century).3 14
• Melting of glaciers and polar ice.15 16 17
• Increasing acidity in the ocean, resulting in bleaching of coral reefs and damage to oceanic wildlife.3 18 19

More info:
Historical Overview of Climate Change Science - Intergovernmental Panel on Climate Change
Causes of Climate Change - WMO

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• 2. R. S. W. Van De Wal, B. De Boer, L. J. Lourens, P. Köhler, and R. Bintanja. "Reconstruction of a continuous high-resolution CO₂ record over the past 20 million years." Climate of the Past 7, no. 4 (2011): 1459-1469.
• 3. a. b. c. d. Bernstein, Lenny, R. K. Pachauri, and Andy Reisinger. Climate change 2007: synthesis report. Geneva, Switzerland: IPCC, 2008.
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• 19. Anthony, K. R. N., D. I. Kline, G. Diaz-Pulido, S. Dove, and O. Hoegh-Guldberg. "Ocean Acidification Causes Bleaching And Productivity Loss In Coral Reef Builders." Proceedings of the National Academy of Sciences 105, no. 45 (2008): 17442-17446.