The Intergovernmental Panel on Climate Change (IPCC) assesses the global risks from climate change. It predicts the average global temperature in 2100 could reach 2.5°C to 7.8°C above late 19th century levels if no action is taken to reduce global greenhouse gas emissions.
Climate change is already affecting the UK and other countries around the world. For example, in the UK:
- the average sea level is rising by 3 mm per year and could increase by 12 to 76cm by the end of the century (compared to 1990 levels)
- the earlier onset of spring and summer is affecting plants and animals
- winter rainfall is arriving in more intense bursts
Globally, climate change is:
- bleaching coral reefs
- shrinking Arctic sea ice
- pushing plant and animal species towards the poles and to higher elevations
- slowing productivity gains for some crops such as wheat and maize (although some regions, including Europe, have seen some recent gains)
In England, average temperatures are between 0.5°C and 1°C higher than they were in the 1970s.
Climate change is also influencing individual weather events. The coastal surge which affected Manhattan in 2012 (during Hurricane Sandy) was 20cm higher as a result of sea level rise, increasing losses by 30%.
Scientists estimate that climate change made the extreme European heatwave in 2003 twice as likely to happen. During this intensely hot period, crop yields fell, power stations closed to avoid overheating and thousands of people died.
The IPCC has identified a range of concerns for the future, including:
- extreme weather events
- severe impacts on the world’s poorest and most vulnerable populations
- environmental and economic damage
- large-scale singular events (such as further sea level rise as major ice sheets melt over Greenland and Antarctica)
These risks will become more pronounced in the future, and new risks will emerge, as greenhouse gas emissions continue to rise. However, they can be limited by reducing greenhouse gas emissions (mitigation) and preparing for change (adaptation).