* Low-lying Singapore preparing for rising sea levels
* Takes climate "insurance" by raising height of new land
* Will make tougher CO2 curbs if global climate pact agreed
SINGAPORE, Jan 27 (Reuters) - A 15-km (10 mile) stretch of crisp white beach is one of the key battlegrounds in Singapore's campaign to defend its hard-won territory against rising sea levels linked to climate change.
Stone breakwaters are being enlarged on the low-lying island state's man-made east coast and their heights raised. Barges carrying imported sand top up the beach, which is regularly breached by high tides.
Singapore, the world's second most densely populated country after Monaco, covers 715 square km (276 sq miles). It has already reclaimed large areas to expand its economy and population -- boosting its land area by more than 20 percent since 1960.
But the new land is now the frontline in a long-term battle against the sea.
Every square metre is precious in Singapore.
One of the world's wealthiest nations in per-capita terms, it is also among the most vulnerable to climate change that is heating up the planet, changing weather patterns and causing seas to rise as the oceans warm and glaciers and icecaps melt.
Late last year, the government decided the height of all new reclamations must be 2.25 metres (7.5 feet) above the highest recorded tide level -- a rise of a metre over the previous mandated minimum height.
The additional buffer was costly but necessary, Environment Minister Vivian Balakrishnan told Reuters in a recent interview.
"You are buying insurance for the future," he said during a visit to a large flood control barrier that separates the sea from a reservoir in the central business area.
The decision underscores the government's renowned long-term planning and the dilemma the country faces in fighting climate change while still trying to grow. It also highlights the problem facing other low-lying island states and coastal cities and the need to prepare.
A major climate change review for the Chinese government last week said China's efforts to protect vulnerable coastal areas with embankments were inadequate. It said in the 30 years up to 2009, the sea level off Shanghai rose 11.5 centimeters (4.5 inches); in the next 30 years, it will probably rise another 10 to 15 centimeters.
Since it was created by the British as a trading port in the early 19th century, Singapore has turned to the sea to expand and has become one of the world's fastest-growing countries in terms of new land area. More land is being regularly reclaimed.
In this pocket powerhouse, there is much to protect. Singapore's recipe for success is to be a city of superlatives to keep ahead of competitors. It is a major Asian centre for finance, shipping, trading, manufacturing, even gambling, with giant casinos as glitzy as those in Las Vegas or Macau.
Much of the city centre is on reclaimed land, including an expanding financial district, a new terminal for ocean liners and a $3.2 billion underground expressway, part of which runs under the sea.
The industrial west has one of Asia's largest petrochemical complexes, much of it on reclaimed islands.
The wealth generated from these sectors has created a $255 billion economy. Per-capita GDP stands on a par with the United States at nearly $50,000, though opposition politicians complain about growing wealth gaps within the island's society.
The U.N. climate panel says sea levels could rise between 18 and 59 centimetres (7 to 24 inches) this century and more if parts of Antarctica and Greenland melt faster. Some scientists say the rise is more likely to be in a range of 1 to 2 metres.
Singapore could cope with a rise of 50 cm to 1 m, coastal scientist Teh Tiong Sa told Reuters during a tour of the East Coast Park, the city's main recreation area.
"But a rise of two metres would turn Singapore into an island fortress," said Teh, a retired teacher from Singapore's National Institute for Education. That would mean constructing more and higher walls to protect against the sea.
Indeed, between 70 and 80 percent of Singapore already has some form of coastal protection, the government says.
The dilemma Singapore faces is mirrored by other coastal cities, such as Mumbai, Hong Kong, Bangkok and New York, though not all have Singapore's financial muscle.
The threat underscores the limits on Singapore's physical growth in terms of further reclamation, costs and managing long-term growth of its population, which has risen from 3 million in 1990 to nearly 5.2 million in 2011.
Topping up reclamation levels "does not fundamentally change the way we approach reclamation -- while we reclaim to meet our development needs, we are cognisant that there is a physical limit to how much more land we can reclaim," a spokesman for the National Climate Change Secretariat told Reuters.
To make more efficient use of existing land, a government agency floated the idea this month of building a science city 30 stories underground.
WINDS OF CHANGE
Climate change presents a host of other challenges.
More intense rainfall has caused embarrassing floods in the premier Orchard Road shopping area.
And the government says average daily temperature in tropical Singapore could increase by 2.7 to 4.2 degrees Celsius (4.9 to 7.6 degrees Fahrenheit) from the current average of 26.8 deg C (80.2 F) by 2100, which could raise energy use for cooling.
Here lies another dilemma. The country is already one of the most energy intensive in Asia to power its industries and fiercely airconditioned malls and glass office towers -- a paradox in a country at such risk from climate change.
The government has focused on energy efficiency, such as strict building codes and appliance labelling to curb the growth of planet-warming carbon emissions and has steadily switched its power stations to burn gas instead of fuel oil.
It has also invested heavily in slick subway lines and promoted investment and research in the clean-tech sector.
But electricity demand is still set to grow. Consumption doubled between 1995 and 2010, government figures show, and long-term reliance on fossil fuels for energy is unlikely to change, given limited space for green energy such as solar.
Balakrishnan said the government is keen to do its part in any global fight against climate change and that pushing for greater energy efficiency made sense anyway in a country with virtually no natural resources.
But there was a limit to how fast it would move, opening the way for criticism from some countries that Singapore was hiding behind its developing country status under the United Nations, which obliges it to take only voluntary steps to curb emissions.
"What we want is a level playing field and unilateral moves are not feasible, not possible, for a small, tiny island state that actually is not going to make a real difference at a global level to greenhouse gases," Balakrishnan said.
Singapore's emissions, though, are forecast to keep growing, having roughly doubled since 1990. The government is looking at putting a price on carbon emissions and perhaps setting up an emissions trading market.
"We're already half way there in the sense we are already pricing everything according to the market," said Tilak Doshi, head of energy economics at the Energy Studies Institute in Singapore.
He pointed to Singapore being the world's largest bunkering port.
"Bunkering is huge in terms of carbon emissions and Singapore can play a key role in how to handle global shipping emissions," he said. "How to handle bunker fuels -- do we tax it, do we cap-and-trade it, do we get bunkering companies to start trading emissions certificates?"
The government has a number of levers to adjust energy policies over time. Against rising sea levels, it is a campaign in progress to tame the tides.
In some cases, it might be better to let the sea reclaim the land in a managed retreat, said Teh, the coastal scientist.