The Earth’s climate system is warming, and it is clear that human activities are influencing the climate system.

The main cause of warming is the increase in the concentration of carbon dioxide in the atmosphere since 1750

Natural and human systems on all continents and across the oceans have been impacted by climate change in recent decades.

Since the 1980’s, each decade has been warmer than the one before

Sea level rose by 19 cm between 1901 and 2010, the Greenland and Antarctic ice sheets are losing mass, glaciers worldwide are shrinking, and Arctic sea ice is decreasing.

Warming will continue as long as greenhouse gas emission continues.

Reducing greenhouse emissions by substantial amounts, and sustaining this reduction, can limit future climate change impacts and their severity.

Options to mitigate climate change, or reduce greenhouse emissions, exist in all sectors of the economy and in many cases mitigation is more cost effective than business as usual.

However effective mitigation is, there will still be impacts on human and natural systems as a result of the greenhouse gases already in the atmosphere. This means that adaptation measures, or actions to reduce the impacts of climate change, are inherently necessary.

Effective adaptation will need policy and action across different scales, from international to local, and across different sectors, from energy intensive industries to individual households.