By Antoaneta Bezlova

SHANGHAI, Jun 7 (IPS) - Few people in this city ever imagine that their future would be defined by the ocean's rising tides. Dire climate change predictions have failed to stir public imagination into conjuring up images of China's most forward-looking city being engulfed by seawaters.

But if Shanghai residents display philosophical nonchalance in refusing to contemplate the worst, city fathers and local experts know they are racing against time to win a knotty battle with global warming.

"The rise of sea levels is indisputable," says Zheng Hongbo, professor at the School of Ocean and Earth Science at Shanghai Tongji University. "We would continue perhaps to search for the exact causes for a long time but in terms of the dangers it poses to Shanghai, we have little time. We have to take it very seriously."

The scenario Shanghai faces may not be as frightening as presented in the acclaimed environmental documentary "An Inconvenient Truth", where former United States vice-president Al Gore warns of the city's submergence. Nevertheless, it has already caused some marine experts to call for drastic counter-measures - from building water gates to prevent sea storms to erecting an ocean embankment all along the coastal line.

Local resident Hu Yang is typical in his aloof reaction to apocalyptical predictions about Shanghai sinking: "It is hard to know for sure about all these scientific predictions but if the sea indeed rises a lot, a mere embankment will not help us."

Still, what Shanghai leaders are bracing for is not a rising seawall but the slow subverting effects of creeping sea water -- coastal erosion, salt water intrusion into the fresh water of the Yangtze river and giant sea waves created by storms.

It is a witches' brew of problems that endanger the very lifeline of this sprawling city of 18 million people -- its constant reclamation of land from the sea to satisfy the needs of its relentless growth.

Scientists have been at odds over who would suffer most from the consequences of global warming. An April report by the Intergovernmental Panel on Climate Change (IPCC) of the Untied Nations analysing the impact of greenhouse gas emissions states that the most vulnerable people in Asia will be the rural poor who rely on river delta for their livelihoods.

But a report by Britain-based International Institute of Environment and Development says Shanghai -- one of China's wealthiest metropolises -- and other coastal cities in Asia, are at risk. Their figures suggest sea levels at Shanghai and Tianjin, a coastal city in China's north, could rise by 60 cm by 2050.

China, which gets much of its energy from coal-fired power stations, is the second-biggest emitter of greenhouse gases that are linked to global warming. The country is in the midst of unprecedented industrialisation and some experts expect it will surpass the U.S. this year as the world's top global-warmer.

China's own studies warn too that the country is particularly vulnerable to climate change because its water and land resources are already stretched thin and many of its major economic centres sit in low-lying coastal areas.

However minimal it may appear, a rise of 60 cm is regarded as a significant threat for Shanghai which lies in a low-elevated area of the Yangtze river delta. The area where the Yangtze pours into the East China Sea sits only 3 - 5 m above the sea level.

"Such rise in sea levels would destroy the fragile equilibrium between economic growth and land reclamation," warns geologist Zheng. "If land growth slows down, the economy would slow down too. This is the biggest worry for the government."

Shanghai is often described as one of the world's biggest construction sites, where a fifth of all cranes are at work. Its building boom over the last ten years has been sustained by continuous land reclamation. The city claims roughly 3,000 hectares of land from the sea every year.

Reclaimed land is now such a feature of Shanghai daily life that few people now pause to think about natural boundaries. Some of the city's impressive new landmarks like its futuristic airport in the financial district of Pudong are all built on reclaimed land. What is more, the city leaders are contemplating creating a brand new eco-city on the marshy land of Shanghai's Chongming island -- itself a land reclaimed from the sea some years ago.

But the coastal erosion could imperil all these projects. Shanghai experts are now proposing to build a water gate at Wu Song Kou Wai near the Yangtze estuary to prevent sea storms and lower the risk of flooding.

It is a plan first put forward in the 1990s but never implemented. In 1998 China suffered devastating summer floods with Yangtze's swollen waters killing more than 3,000 people and leaving 14 million homeless.

Last month China meteorologists warned of more typhoons, floods and drought this year than at any time in the past decade because of global climate change. The most severe floods since 1998 might hit the Yangtze this summer, Zheng Guoguang, director of the China Meteorological Administration told a press conference.

As the country braces for extreme weather conditions, the proposal of building a water gate in Shanghai has been dusted off and studied anew. Local experts argue building such a gate would be less costly and more effective than raising and re-enforcing the current river dykes.

"We have been looking at plans to build a water gate near the river estuary as a way of lessening the flooding aftermath of a severe sea storm," says Zhang Zhenyu, spokesman of Shanghai Flood Risk Information Centre under the Shanghai Water Administration Bureau. With global warming at play, predictions of the ferocity of future sea storms have been continuously revised.

Another proposal -- to erect sea walls, the equivalent of a coastal Great Wall -- has been put forward by experts in Tianjin in the hope that such embankments can also fend off the advancing tides.

But some have dismissed such proposals as missing the core of the crisis. Shanghai-based columnist Chen Weihua argues that instead of building sea walls, China should tackle its deteriorating environment to preempt doom-case scenarios for its coastal cities.

"Erecting a strong embankment may not make people feel safe," Chen said in a recent opinion piece published in the ‘China Daily'. "Just look at the numerous cases of fortifications rupturing along China's major rivers and lakes in the last few decadesà the cracking of a sea wall will surely inflict damage of much larger magnitude, considering the might of the ocean as demonstrated in the Asian tsunami of December 2004."

In the past, Beijing has argued that industrialised countries are the ones responsible for creating the bulk of the emissions historically and they should take lead in tackling global warming. This week Chinese leaders promised to integrate efforts to reduce such emissions into their overall plans for economic development but rejected calls for capping them. (END/2007)