Act now on global warming before it's too late for Thailand's coastline and coral reefs

STORY BY NORMITA THONGTHAM, PHOTOS BY DR NALINEE THONGTHAM

Sediment is killing this coral reef.

Thailand's coral reefs, which have attracted tourists since the 1960s, could be lost in 50 years if carbon dioxide (CO2) emissions continue at current rates over the next eight to 10 years.

The warning came from Dr Marea Hatziolos, senior coastal and marine specialist at the World Bank, who was one of the scientists who warned of the impact of climate change on coral reefs around the world at the UN Climate Change Conference in Bali, Indonesia, last December.

"The current level of CO2 equivalent accumulation in the atmosphere is 430ppm [parts per million]," she said. "At current rates, an accumulation level of 450ppm is expected to be reached by 2015, and scientific evidence suggests that once CO2 accumulation in the atmosphere reaches 550ppm, coral reef ecosystems will be extensively and irreversibly damaged," and reef-building corals will largely disappear.

The Washington, DC-based expert on coastal zone management recently spoke at a seminar organised by the World Bank at its Bangkok office in Siam Tower, Rama 1 Road, recently. The event attracted a full house comprising mostly of marine biologists, researchers and officials involved in coastal management and protection.

Although coral reefs occupy only 0.2 per cent, or 284,300km2 - a little more than half the size of Thailand - of the ocean floor, they contain the most diverse ecosystems on the planet, she said. They provide a habitat for many species of fish, crustaceans and other marine life, and serve as buffer against strong waves that erode coastlines during storms.

Coastal zone management expert Dr Marea Hatziolos warns that because of its long coastline, Thailand is extremely vulnerable to sea level rise due to climate change.

The economic value of coral reefs, as a source of food for at least 2.6 billion people in developing countries and as a source of livelihood for some 150 million people involved in fishing and related industries, not to mention their role in tourism and coastal protection, could not be put in monetary terms, Hatziolos said.

"It would be in billions of dollars," she said. "Reef benefits to coastal protection alone are estimated to be $5 billion."

Seventy-five per cent of the world's coral reefs are found in the Indo-Pacific region; however, studies found that coral cover in the region is declining at the rate of one to two per cent annually, due to destructive fishing, tourism, sedimentation caused by coastal development, eutrophication due to untreated wastewater run-off, dredging and climate change.

Disease has also taken its toll on coral reefs. Scientists are now carrying out research to pinpoint the cause of the disease, Hatziolos said, but there is strong evidence that it is linked with pollution from aquaculture, exacerbated by increases in water temperature due to climate change.

Climate change is manifested by a rapid rise in temperatures all over the world. Only 30 years ago scientists were warning that global warming would change precipitation patterns significantly, with heavy rainfall in some areas while others would be very dry. Extreme weather conditions such as storms, floods, droughts and heatwaves would become more intense and more frequent, and sea levels would rise, the scientists warned.

Thailand's coral reefs are threatened by global warming. Rise in water temperatures by as little as 1C above the average temperature of the warmest month of the year could trigger coral bleaching.

bOne of many ongoing coastal developments that mar Phuket's hillsides and discharge sediment that smothers coral reefs.

These changes can already be observed, according to the report East Asia Environment Monitor 2007: Adapting to Climate Change, published by the World Bank.

"In the last few years there have been widespread changes in extreme temperatures, droughts have become longer and more intense, the frequency of heavy precipitation has increased over most land areas, and arctic sea ice has shrunk by 2.7 per cent per decade, resulting in a rise in sea level that is now beginning to submerge small island countries like Kiribati and Nauru in the South Pacific," the report said.

Thailand has 2,880km of coastline along 136 districts in 23 provinces, thus it is extremely vulnerable to sea level rises due to climate change. A one metre rise will not only sink Bangkok and low-lying areas, resulting in destruction of infrastructure, loss of beaches and irreversible damage to coastal ecosystems like mangrove forests and coral reefs, but also cause land subsidence and coastal erosion.

"A one metre rise means a 3km intrusion of saltwater into productive land areas and drinking water supply, leading to a large-scale human migration," Hatziolos warned.

Her warning seems far-fetched, but according to a study by the Department of Marine and Coastal Resources (DMCR), coastal villagers in Ban Khun Samutchin in Samut Prakan have moved their houses eight to 11 times to escape land erosion that has eaten up 11,000 rai of their land over the past 20 years.

Within just a few years, Wat Khun Samutrawas, also in Samut Prakan, has lost 70 rai of land to coastal erosion and rising sea levels, and now only four rai remains before the temple is submerged for good.

According to the DMCR report, Thailand Environment Monitor 2006, 80 per cent of global coastlines are facing erosion at various rates. In Thailand, coastal erosion has been observed for 485km in the Gulf of Thailand from Trat to Narathiwat, and 114km along the Andaman coastline.

The causes are mostly man-made, such as the clearing of mangrove forests for wood or aquaculture; groundwater drainage and land subsidence; sand mining; construction of structures such as dams, ports and harbours that obstruct the natural patterns of waves, erosion and sedimentation; and construction of industrial estates along the coastline.

Degradation of coral reefs that act as natural tidal barriers and buffers is also cited as another cause of coastal erosion.

Erosion has become quite severe in the last decade, the report states, with the Upper Gulf of Thailand experiencing erosion at a faster rate than was originally anticipated. A simulation indicates that without intervention, in 20 years coastlines will retreat inland by 1.3km as they are eroded away.

The DMCR report shows 30 critical erosion spots in the whole of Thailand, 22 of them in provinces along the Gulf of Thailand and the rest on the Andaman coast. The highest erosion rates were observed in Bangkok, Samut Prakan, Samut Sakhon, Samut Songkhram and Chachoengsao, which have already lost 18,000 rai of land to coastal erosion.

Ban Khun Samutchin in Tambon Laem Fa Pha, Phra Samut Chedi district of Samut Prakan, is now a pilot site for DMCR erosion prevention projects.

Thailand has 2,130km2 of coral reefs, much smaller than Indonesia, which has 51,020km2, Australia (48,960km2), or the Philippines (25,060km2) but Thailand's coral reefs are among the most threatened in the world. They are over-fished, smothered by sediment coming from coastal development, choked by algal bloom on nutrient-rich sewage and fertiliser run-off, damaged by irresponsible tourism, and stressed by the ever warming sea waters.

It is not known how a rise in sea levels - now just a matter of when, not if - would affect Thailand's coral reefs, but studies have suggested that global warming will reduce the world's coral reefs in an extremely short timeframe. This does not augur well for Thailand's thriving diving tourism industry.

"The level of the Andaman Sea has not risen noticeably yet," Dr Somkiat Khokiattiwong of the Oceanography and Marine Environment Unit at the Phuket Marine Biological Centre (PMBC), said. "But PMBC researchers found that water temperatures in the Andaman Sea have risen significantly over the last 50 years."

A rise in water temperature of as little as 1C above the average temperature of the warmest month of the year could trigger coral bleaching.

"What's more, cool upwellings are happening more often and becoming more severe," Somkiat added. Cool upwellings deprive the water of oxygen, killing fish and other marine life in coral reefs.

For years, PMBC researchers and DMCR officials have been involved in the conservation and rehabilitation of coral reefs, and following the 2004 tsunami there has been increased public awareness and participation in coral protection. However, unless CO2 emissions are reduced, global warming will steadily get worse.

A survey by the World Resources Institute in 2000 found that Thailand contributed four per cent to the stock of greenhouse gases in the atmosphere. Greenhouse gases predominantly come from energy use - the burning of fossil fuels in power generation, transport, industry and buildings - as well as agriculture and deforestation.

We should reverse this pattern by planting more trees, protecting and restoring mangroves, using clean and efficient production technologies, driving less and taking public transport more. Everyone must get involved in reducing our carbon footprints, for, after all, it will be us who will eventually suffer if we don't.

Quoting Dr Nguyen Huu Ninh, co-author of the Intergovernmental Panel on Climate Change 4th Assessment Report, and co-recipient of the Nobel Prize for Peace 2007, Hatziolos said, "The responsibility belongs to all. Everyone must do their best to protect the environment - for themselves, for their family, for the whole society and for the entire human race."