1. Without greenhouse gases, average temperatures on Earth would be -18°C (0°F).

2. Carbon dioxide is responsible for about 70% of man-made global warming.

3. Most scientists say that global warming of more than 2°C would be disastrous.

4. Emissions reductions of more than 80% by 2050 are necessary to limit warming to 2°C.

5. Global temperatures have increased by a little less than 1°C during the last 100 years.

6. Since 1750 methane levels have increased by about 150%.

7. Methane locked in permafrost soils could trigger unstoppable climate change if released.

8. Methane's warming potential is 25 times higher than that of CO2 over a 100 year period.

9. Over a similar period, nitrous oxide is about 300 times stronger than CO2.

10. Carbon dioxide, once emitted, has a warming effect over several hundred years.