Climate change is already here. Since the 1960s, Portsmouth has recorded:
- an average increase of 1°C to both winter and summer temperatures
- an average of seven less frosty days a year
- an increase of 7% on annual rainfall, that’s an additional 50 mm of rain
Locally, we’ve already experienced:
- flooding from heavy rain
- injuries from cold snaps and heatwaves
- landslides
- tornados
- damaged buildings and roads
- travel delays
- disrupted public services such as refuse collection
- cancelled events
Portsmouth’s climate change outlook
Climate models use historical data and pair that with predictions of likely greenhouse gas emissions to work out the likely future climate.
Using recent averages, models predict that Portsmouth in the 2040s is likely to have:
- average summer maximum temperatures could be over 2°C higher than now
- summer rainfall could fall by 15%
- average winter minimum temperatures could be over 1°C higher
- winter rainfall could increase by 12%
- sea level could be 21 cm higher
The 2080s might be beyond some of our lives, but not your children’s.
Using recent averages, models predict that Portsmouth in the 2080s are like to have:
- average summer maximum temperatures could be over 6°C higher
- summer rainfall could fall by 27%
- average winter minimum temperatures could be over 3°C higher
- winter rainfall could increase by 38%
- sea level could be 57 cm higher
Data sources: The Met Office
This means Portsmouth summers are getting progressively warmer and drier, with an increased chance of drought, wildfires, and heat stress, particularly to those who are more exposed, such as outdoor workers, or residents who are more vulnerable such as older people and babies, and those with underlying health conditions. The effects of heat will be felt most in dense urban areas of Portsmouth like Somerstown, Portsea, Southsea, Fratton where there is lots of hard surfaces and little vegetations such as trees to help cool the air. This is called the ‘urban heat island’ effect which means urban areas are often even hotter than surrounding areas.
Winters will be warmer and wetter, meaning an increased frequency and severity of flooding. An increased frequency of extreme weather events such as heatwaves, heavy rain, storms and extreme cold.
As a low-lying coastal city, Portsmouth is at risk from continually rising sea level.
Climate change impact to our environment
Plants and animals will also find it harder to live in our city. Some species might disappear, and new species might appear. Seasons might start earlier or later and our wildlife might struggle to adapt.
The impacts to us, our environment and society will be enormous if we do not reduce our emissions to avoid the worst of climate change.