Key impact - Flooding

About 10 per cent of the three regions area is already considered a floodplain. Climate change is expected to bring more storms in the winter and intense bursts of rainfall in the summer, so the number of homes affected by flooding will increase.

It's often assumed that floods are the overflow of water from rivers or the sea, covering low-lying land. However, floods can also be caused by sewers and storm drains that can cope with ordinary rainwater but not with an increased volume of water from intense storms. If there's nowhere for the rain to drain away to, it will run across the land, causing flash flooding.

Floodwater that has been contaminated by sewage is more expensive to clean up than river water. It can spread disease, so anything it has come into contact with needs to be disinfected.

There's a lot of pressure to build new houses in the three regions given population growth and more people choosing to live alone. New developments on the floodplains are at risk and also create problems for existing homes in the surrounding areas because they use up valuable floodwater storage.

Flood defences can be used to help to protect towns and cities from flooding, but it's just not possible to build barriers around everywhere that's at risk.

The combination of climate change and new developments means that homes that already flood could do so more deeply and increasingly often, and homes that have never previously flooded will be at risk.