Southeast Asia is around 11,000 km from the Arctic and 9,000km from Antarctica, but it will be hardest hit by rising sea levels caused by melting and collapsing ice sheets if carbon emissions remain at business-as-usual levels and temperatures continue to rise.
The region, with about 650 million inhabitants, is particularly at risk because of its population density and the fact that around 450 million people live in low-elevation coastal zones.
“The issue to do with the tropics is a gravitational attraction to existing ice sheets,” said Professor Benjamin Horton, a principal investigator at the Earth Observatory of Singapore at Nanyang Technological University. “Ice has huge mass — Antarctica is huge — water is attracted to that. If the ice sheets lose mass, the water is repelled from the ice sheets and the maximum change in sea level rise from a melting ice sheet is felt in the tropics.”
Speaking at the third Partners for the Environment Forum organised by the Singapore Ministry of the Environment and Water Resources and the British High Commission last week, Horton added: “Antarctica is a sleeping giant that we believe is awakening. It has over 60 metres of sea level within it. So you only need to melt a small percentage of (ice sheets) to have catastrophic implications.”
The observatory as well as the Centre for Climate Research Singapore (CCRS) have launched new initiatives to better understand relative sea level change and mitigate its impact in the region.
Other factors that make Southeast Asia particularly vulnerable to rising sea levels include the fact that it is heavily influenced by tectonics, which can cause land to either rise or sink during earthquakes.
Researchers from the observatory have also found that the Indonesian capital of Jakarta is sinking around 17 centimetres a year due to ground water withdrawal for agricultural, industrial, and commercial uses.
The consequences are stark for countries like Singapore, where 30 per cent of the island is less than five metres above the mean sea level. Rising sea levels is also a “sovereignty issue”, said Horton, who spoke at the session on climate change realities alongside CCRS director Erland Källén and Professor Herbert Dreiseitl of urban planning and liveability consultancy DreiseitlConsulting.
The ‘perfect storm’
The CCRS has found that in the rare scenario of higher sea levels, high tide and high storm surge all occurring at once, sea levels could rise almost four metres above the current mean and overwhelm Singapore’s low-lying coastal areas.
Singapore Minister for the Environment and Water Resources Masagos Zulkifli highlighted the finding in his keynote address at the forum.
“If we push our imaginations further, in the extremely rare occurrence that a tropical storm happens at sea — sending us surge waters that we can’t keep out — and a heavy rainstorm happens inland — bringing down rainwater we can’t drain away — both at the same time, we could have the ingredients of a ‘perfect storm’”, he said.
While this is an extremely rare scenario based on current science, it is not inconceivable in the future, he added.
To mitigate rising sea levels, Singapore has started building new infrastructural projects such as the Tuas mega port and Changi Airport’s Terminal 5 on higher ground. Terminal 5 will be 5.5 metres above the mean sea level, while the Tuas terminal will be built more than two metres higher than the highest water level observed, the government has said.
Since 2011, Singapore has also spent around S$1.8 billion on drainage improvement and will spend another S$400 million in the next two years to upgrade and maintain the country’s drains.
The CCRS, which is the research arm of the Meteorological Service Singapore, will also be launching a S$10 million national programme to “develop more robust sea level rise projections”.
“We will share what we know and hope that we can also help our neighbours plan for their adaptation to climate change,” said Minister Masagos.
Climate change is “the ultimate threat to human survival”, and climate science is telling us that “it’s not a matter of if the sea level will rise, but a matter of when and how much”, he said.
But the extent of changes is not a foregone conclusion. “It’s not all doom and gloom,” said Horton. “We have a choice.”
If emission targets of the Paris Agreement are met, countries will be able to adapt to the rate of sea level change and coastal ecosystems in the region “will also continue to live and thrive”, he said.
A high-emission, business-as-usual scenario will result in a 30 millimetre sea level rise per year. There is currently no engineering solution to protect against such a scenario, which will also bring about the extinction of mangroves and corals in Southeast Asia, said Horton.
Change needs to happen quickly, especially since oceans will continue to warm even after carbon-dioxide levels in the atmosphere stabilise, said Professor Källén.
Laws to create right conditions
Governments can do more to accelerate change, and one way is by providing the legislative framework to create the right conditions for it.
In her opening remarks at the forum to over 200 attendees from businesses, organisations, and guests from the UK, Ms Kara Owen, the British High Commissioner to Singapore, highlighted Britain’s commitment to climate change.
It was the first country to introduce a legally-binding, long-term emission reduction target through the Climate Change Act in 2008. In June this year, the UK also announced a new law in support of a net-zero emissions target by 2050. From April 2020, all cotton buds, plastic straws, and stirrers will also be banned in England, with Wales and Scotland taking a similar approach.
“Green growth” is possible, she said.
“Each society, each business, each country (and) each government wants to maintain competitiveness and efficiency with economic growth, and we have found that (climate action) has not come at an economic cost,” said Ms Owen. “Between 1990 and 2017, we reduced our emissions by 42 per cent while the economy grew by 72 per cent.”
Ms Claire Kneller of the Waste and Resources Action Programme (WRAP), a non-profit organisation from the UK, also shared how “you can change people’s behaviour to a certain degree by changing the environment that they’re functioning in”. For example, changing the national context through legislation or changing product design can influence the way people behave and interact with resources and the environment.
The UK’s five pence (US$0.06) plastic bag charge, which has reduced the use of plastic bags in England by 85 percent from 2015 (or about 9 billion bags taken out of circulation), was also generally well-received by the public as “people could see that it was for a good reason”, she said.
“There has to be much faster (and) stronger government action,” said Ms Kneller, the non-profit’s head of international food.
“Because this is such a huge global problem, my view is that we can only tackle it if the powerful and influential governments of the world are not just the saying this is a huge problem and acknowledging it, (but) they’re also saying: these are the transformative changes that we are going to make to our economy to address it.”
