Scientists have developed a new method for revealing how sea levels might rise around the world throughout the century to address the controversial topic of whether the rate of sea level rise is currently increasing.

 

The international team of researchers analyzed data from 10 long-term sea level monitoring stations located around the world. They looked into the future to identify the timing at which sea level accelerations might first be recognized in a significant manner.

 

Lead author Dr Ivan Haigh said: "Our results show that by 2020 to 2030, we could have some statistical certainty of what the sea level rise situation will look like for the end of the century. That means we'll know what to expect and have 70 years to plan. In a subject that has so much uncertainty, this gives us the gift of long-term planning.

 

"As cities, including London, continue to plan for long-term solutions to sea level rise, we will be in a position to better predict the long-term situation for the UK capital and other coastal areas across the planet. Scientists should continue to update the analysis every 5 to 10 years, creating more certainty in long-term planning — and helping develop solutions for a changing planet."

 

The study found that the most important approach to the earliest possible detection of a significant sea level acceleration lies in improved understanding (and subsequent removal) of inter-annual (occurring between years, or from one year to the next) to multi-decadal (involving multiple decades) variability in sea level records.

 

"The measured sea levels reflect a variety of processes operating at different time scales," says co-author Dr Francisco Calafat. He adds, "One of the main difficulties in detecting sea level accelerations is the presence of decadal and multi-decadal variations.

 

For example, processes associated with the North Atlantic Oscillation have a strong influence on the sea levels around the UK over multi-decadal periods. Such processes introduce a large amount of 'noise' into the record, masking any underlying acceleration in the rate of rise.

 

Our study shows, that by adequately understanding these processes and removing their influence, we can detect accelerations much earlier."