In a world beset by climate change, even local weather has global implications. Thailand's historically heavy monsoon this year – swamping several northern provinces and threatening low-lying Bangkok – fits into a troubling list of recent weather events around the world, with grave implications for what lies ahead.
Alongside the devastating floods of 2010 in Australia, Brazil, Pakistan, Sri Lanka, and West Africa, or the abnormally early snowstorms in the northeast of the United States half a world away, these disasters drive home the point that extreme weather is occurring more frequently. They raise the urgency of improving disaster preparedness, climate adaptation and mitigation before it is too late.
According to the EM-DAT database of the Centre for Research on the Epidemiology of Disasters, the global incidence of floods and storms tripled from about 50 a year in the 1980s to 150 a year in the 2000s. The sharp spike in such water-related disturbances illustrates the ominous links among rising CO2 levels in the air, global warming and extreme precipitation.
Human communities are becoming increasingly vulnerable to flooding. Millions of people are now endangered because of population growth in coastal cities and on flood plains. And as the environment is degraded, natural defenses are destroyed, worsening impacts.
Climate change only compounds these issues through higher sea levels, heavier precipitation, and more frequent and severe storms.
Areas in Southeast and South Asia are highly vulnerable. In the new Climate Change Vulnerability Index from Maplecroft, a risk management group, five of six cities classified as "extreme risks" among the world's fastest growing urban areas are in Asia: Kolkata in India, Manila in the Philippines, Jakarta in Indonesia, and Dhaka and Chittagong in Bangladesh.
Guangzhou, Mumbai, Delhi, Chennai, and Karachi are "high risks".
Thailand's floods illustrate what is at stake. Since heavy rains began in August, nearly 400 people died as the floods moved toward Bangkok. The poor were hardest hit and are likely to suffer most as the floods recede, such as through the spread of water-borne diseases.
The outcry from the owners of many thousands of swamped businesses and factories in the worst-affected areas also demands attention. Moody's credit rating agency estimated flood damage at $6.5 billion, a figure with global implications because Thailand is an important link in global supply chains for car parts, electronics, and computer hardware. Many thousands of jobs are threatened as businesses stand idle and economic growth slows.
If the city's flood defenses had failed under more unfavorable circumstances – a bigger tidal surge in the Gulf of Thailand or unrelenting rainfall in Bangkok – millions more would have suffered and havoc may have ensued in one of Southeast Asia's most important hubs.
No longer can we respond with cleanup and reconstruction alone. Investing in adaptation – protecting the environment, controlling development, improving warning systems – is equally important.
And unless action is taken to mitigate climate change, all bets are off.
Local degradation of the environment must be reversed. Wetlands provide a buffer against disasters, but 50 percent of them worldwide have been lost over the past century alone.
Replanted mangroves, for example, reduced the ravages from a typhoon in Vietnam in 2000 and a cyclone in southern India in 2002. Other forests are also key to protecting against flash flooding and landslides.
Better land-use planning and water management are needed. Land-use regulations, which have for the most part been risk blind in much of Asia, must ensure that people live in places less likely to be affected by flooding or severe storms. Stronger flood action plans and better water management are urgently needed.
Early warning systems for extreme weather events must be expanded, stressing both robust technologies and public education. In Bangladesh in the early 1970s, a cyclone killed more than 300,000 people. But after the country put in an extensive early warning system, and built robust programs for community-based preparedness, evacuation and mitigation, a recent cyclone of similar intensity took 3,000 lives.
Mitigating climate change is the responsibility of developed and developing nations. Even as the risks from natural calamities become evident, CO2 emissions continue to climb. Achieving greater energy efficiency, reducing energy wastage, curbing deforestation or investing in green technologies are looking downright necessary – in countries' own self-interest.
Even as this crisis subsides in the sprawling Thai capital, there's a rising tide of concern about what these floods portend in the coming years.