London | The upper depths of the world’s oceans have warmed significantly over the last 20 years leading to severe hurricanes, storm surges and an increase in the number of icebergs, a new study has found.
The study, led by Grant Bigg and Edward Hanna from the University of Sheffield in the UK, has showed how increase in sea temperatures has changed global weather patterns.
The scientists have shown that the rise in ocean temperatures has caused an increase in the number of severe hurricanes and typhoons, such as Hurricane Katrina, which devastated New Orleans in 2005, and Typhoon Haiyan, which caused massive destruction in the Philippines in 2013.
Hurricanes have even been observed in the South Atlantic for the first time since satellite records began in the 1970s.
The area was traditionally viewed as an unlikely region for hurricane formation because of its cooler sea surface temperatures; however in 2004 conditions were more favourable than normal due to warmer ocean temperatures, spawning Hurricane Catarina off the coast of Brazil.
The report also shows that warmer seas have resulted in a significant loss of ice in the Arctic region.
The atmosphere in the Polar Regions has warmed at about twice the average rate of global warming with Arctic coasts experiencing a rise in the occurrence of storm surges.
This increase in storm surges can have a detrimental effect on fragile ecosystems in the area, such as low relief tundra, underlain by permafrost, according to the report.
Warmer oceans have also caused a distinct change in El Nino events – the warmer currents associated with the cycle have now been observed towards the central Pacific rather than the west, scientists said.
“Many people may associate warmer seas with the pleasant weather conditions they’re used to experiencing while on holiday, but the fact of the matter is that an increase in sea temperatures is having a huge impact on the world’s weather,” said Bigg.
“Our study has shown that severe hurricanes, storm surges, melting ice in the Arctic region and changes to El Nino are all being caused by sea temperatures rising across the planet,” he said.
“These are all things that can have a devastating impact on the way we live our lives,” Bigg said.
The report also predicts what implications warming seas may have for our planet in the near future if current trends continue.
The continued warming of tropical oceans is likely to cause stresses on ecosystems, such as coral bleaching, and stronger tropical cyclones.
It may also cause changes to climate over land, which could reduce crop production as temperatures rise.
The report was presented at the International Union for Conservation of Nature and Natural Resources (IUCN) World Conservation Congress in Hawaii.