Our changing climate, caused by greenhouse gas emission, is driving global sea level rise and coastal change at ever increasing rates. As a result the risk of coastal flood and erosion will increase substantially in Bude over the coming decades.
Several factors contribute to sea level rise, each linked to rising global temperatures. The largest factor is thermal expansion, in which seawater expands as it becomes warmer.
Importantly, there is a substantial time lag between atmospheric temperatures rising and water expanding, mainly because of the vast amounts of water in the great ocean depths. It means that even if all greenhouse gas emissions were to stop today, sea levels will continue to rise for many years to come.
Scientists have calculated that the world has already emitted sufficient greenhouse gases to drive a global sea level rise of around one metre. To make matters worse, greenhouse gas emissions are still growing year-on-year and at increasingly faster rates. It’s not a question of if, but rather a question of when.
In the 20th century, the global average sea level rose at a rate of around 1.7mm per year. This rate of increase is now accelerating. Newlyn in Cornwall provides the UK’s longest ongoing sea-level time series. Analysis of Newlyn’s tidal gauge records from 1981-2016 shows the sea level rising by an average of 2.3mm per year, resulting in an overall local sea-level rise of approximately 7cm (nearly three inches) over 35 years.