The Intergovernmental Panel on Climate Change (IPCC) assesses the global risks from climate change. It predicts the average global temperature in 2100 is likely to be between 3°C to 5.5°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, the UK Climate Projections 2018 (UKCP18) project found that:
- the average sea level has already risen by around 16cm in the last 100 years and could increase by 8 to 115cm by the end of the 21st century (compared to the 1981-2000 average) depending on location and future greenhouse gas emissions
- average temperatures in England over the last decade (2008-2017) were around 0.8°C higher than they were in the 1970s and 1°C higher than pre-industrial times (1850-1900)
- extremely wet days are increasing
Globally, climate change is:
- threatening the survival of certain ecosystems
- exacerbating extreme weather events (e.g. heat waves, drought, extreme rainfall, and coastal flooding)
- altering sea ice concentrations, river flow and coastal erosion
- 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)
Analysis from UKCP18 showed that the chances of seeing an event like the 2018 hot summer was low in the past (less than 10% probability for 1981-2000) but will be common by the 2050s (around 50% probability). Such intensely hot periods result in direct impacts on people (lower productivity, illness and increased mortality), crop yield reduction, transport and energy production issues due to overheating. There is also evidence that climate change increased the likelihood of some of the floods that have occurred in the UK.
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).