Famous attractions such as the Sydney Opera House and the Statue of Liberty are at risk of being lost under rising seas caused by climate change, according to a new report.

The study, published in the journal Environmental Research Letters looked at the impact rising sea levels would have on UNESCO World Heritage Sites over 2,000 years, but the authors warned that the impacts would be felt much sooner if measures aren’t taken to boost flood defences.

The scientists said a global temperature increase of 3C (37.4F) by the end of the century – causing ice sheets to melt and warming oceans to expand – would see 20 per cent of the world’s 720 world heritage attractions affected.

Lead author Professor Ben Marzeion, of the University of Innsbruck in Austria, said Europe’s cultural treasures will be particularly vulnerable to the rising sea levels.

The famous canal city Venice is at risk, as is the leaning tower of Pisa, he said, while the city centres of Bruges in Belgium, Naples in Italy and St Petersburg in Russia are all in jeopardy, as are Westminster Abbey and Westminster Palace, according to the study.

"It's relatively safe to say that we will see the first impacts at these sites in the 21st century," Marzeion told the Guardian.

"Typically when people talk about climate change it's about the economic or environmental consequences, how much it's going to cost. We wanted to take a look at the cultural implications."

The report examined the impact across 2,000 years as such a timeframe eradicates potential anomalies, with scientists still in debate over how quickly global sea levels will rise.

The UN's climate science panel predicted sea level rises of 26-82cm (10.2-32.3ins) by 2100 in a report last September, while a recent study published in Quaternary Science Reviews suggested this was a conservative estimate, saying the actual increase would be 0.7-1.2m (2.3-4ft).