Climate change expert to investigate rising sea levels in the Maldives

Michael O’Leary is one of six international delegates investigating how the Maldive Islands would respond to a rise in sea level.
The breakwater and harbour in the Maldives’ capital, Male. Completed in 1990 at a cost of $70 million, the tetrapod wall is designed to prevent coastal erosion along the edges of the Male atoll. The groynes are designed to stabilise beaches by preventing this natural movement of beach sediment.

6 July 2011

Rising sea levels as a result of global warming could seriously impact the picturesque Maldive Islands, according to University of Notre Dame Australia academic, Dr Michael O’Leary.

Dr O’Leary is one of six delegates from around the world invited on a three-week expedition to the Maldives. They will investigate how the low-lying archipelago can survive a rise in sea level.

He will undertake his investigation as part of REEForm, a working group established by the International Association of Geomorphologists to examine reef and reef landform responses to past, present and future environmental changes.

Situated roughly 700km south west of Sri Lanka, the Maldives (consisting of more than 1000 islands) has a height elevation of just 1.5m above sea level, making it the lowest lying nation in the world.

Dr O’Leary’s research background is in using past sea levels as a proxy to understand how the polar ice sheets in Greenland and Antarctica have waxed and waned with changing temperatures, causing the oceans to increase and decrease their volume.

While completing his PhD studies in the reconstruction of past sea levels off the Western Australian coast, Dr O'Leary found that as recently as 120,000 years ago sea levels rose between 2m and 6m above present, over a period of 100 to 1000 years.

If this was the case today, the whole of the Maldives could become submerged.

Unlike Australia where, if sea levels were to rise in excess of 2m, its population could move inland, the 400,000 people living in the Maldives would have nowhere to retreat.

“What we are trying to understand is whether coral reefs and reef islands will keep up, catch up, or simply give up in response to rising sea levels,” Dr O’Leary said.

“In order to do this we need to understand how these low reef islands evolved over the last 10,000 years to changing environmental states and how they might respond to any possible future environmental changes.

“If you raise sea level, yes, you may submerge the island, but potentially you may create an environment where sea level constrained coral reefs switch on and produce sediments which can build up the island, essentially keeping pace with rising sea level.”

While discussions about the human footprint on climate change continue in political circles, Dr O’Leary maintains that over the last million years the Earth regularly experiences (every 40 to 100,000 years) fluctuations in sea level of more than 100m, primarily due to changes in the earth’s orbit around the sun.

He says the earth’s orbit is never fixed and during periods when the planet is at a greater distance from the sun, the temperature is colder, the ice sheets are larger and the ocean levels are reduced. The inverse occurs when the planet is closer to the sun.

Irrespective of his findings, Dr O’Leary said people shouldn’t become complacent over climate change.

“If you go back 18,000 years ago, the sea level was about 120m lower than it is today,” Dr O’Leary said.

“About 125,000 years ago during the previous inter-glacial era, a warm period similar to what we’re experiencing now, there’s evidence along the WA coast that shows sea levels were about 2m higher than today.

“We all should be concerned about climate change, but it is a natural process and the issue at the moment is to what degree human activity is accelerating that process.”

Media Contact: Leigh Dawson (+61) 8 9433 0569, Mob (+61) 0405 441 093

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