What do you Know about climate change?

The Intergovernmental Panel on Climate Change released its fifth assessment today, and here's what you need to know.

1. Climate change is real.

2. Climate change is happening now.

Twelve of the hottest 13 years on record have occurred since 2000. In May of 2013, the amount of carbon dioxide in our atmosphere exceeded a concentration of 400 parts per million (ppm) by volume for the first time in millions of years.

3. Humans are the cause.

The single biggest factor in rapid climate change is the “greenhouse effect.” Greenhouse gases, such as carbon dioxide, methane, nitrous oxide, and chlorofluorocarbons are all produced in large amounts by human activity.

4. The worst impacts can only be prevented by our actions.

The extreme weather that is a result of climate change - record droughts in the United States and Brazil, uncontrollable flooding in India, Pakistan, and China - will increase in frequency and the rising sea level and acidification of the oceans will accelerate, unless we are able to change the current trends.

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