It is a definite recipe for disaster, barely short of apocalypse. Thousands may die, millions get affected, and assets worth billions of dollars get destroyed. As human-induced greenhouse gases increase, so will extreme weather events like floods, heat waves and droughts.
The latest report of the Intergovernmental Panel on Climate Change (IPCC) presents this grim picture. Surely then, the Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation, which will be released in Uganda on November 18, is no harbinger of good news.
The report, culled from scientific studies undertaken across the world, makes a strong link between extreme weather events and greenhouse gas concentrations from anthropogenic emissions. This, it says with two-thirds surety, would decrease the number of cold nights in a year and make days warmer. Since the 20th century heat waves, like the one in Asia in 2007, have increased. Droughts have intensified since 1950 and are prolonged, especially in western Africa and southern Europe.
The report also names greenhouse gases as the probable culprit for increase in the mean sea level and tidal intrusions.
Over the years, nations have suffered huge losses because of extreme weather events. The estimate for annual global monetary loss from such events between 1980 and 2010 ranged between a few billion US dollars and 225 billion US dollars. The year 2005 was worst hit, as Hurricane Katrina swept New Orleans in the US. However, monetary loss in developing nations is difficult to ascertain, the report clarifies. Cultural heritage, ecosystem services, informal and undocumented economy cannot be monetised.
Between 1979 and 2004, 95 per cent of all deaths from natural disasters occurred in developing nations. If the loss is valued in terms of gross domestic product (GDP), between 2001 and 2006 low income countries lost about 0.3 per cent due to these freak events. Developed nations lost only about 0.1 per cent of their GDP. But the worst hit were countries with rapidly expanding asset base, like India and China, which lost about one per cent of their GDP.
Asia seems to have borne the maximum brunt of intensified weather events between 2000 and 2008, the report notes.
By the middle of this century, annual daily temperatures could gradually increase by 3°C, peaking at 5°C towards the century’s end.
The frequency of cyclones may remain the same, the report says, but their intensity and maximum wind speeds are likely to increase. This will increase the number of people who get affected by it. In 1970s, the number of people exposed to tropical cyclones was about 73 million. With increased intensity, the number may double by 2030. East Asia, including China, Japan, the Koreas and Russia, is most vulnerable, accounting for more than 90 per cent of the hits (see map).
The same holds true for floods. The IPCC sounds a red alert on inundations due to high rainfall events like the one in Mumbai in 2005. The Maximum City received half of the season’s rainfall within a day (see ‘Megacities in danger’). Such events occur once every 20 years. By the end of the century, these may become as frequent as once every five years. About 86 million people are likely to get exposed to floods by 2030, about two-and-a-half times more than in 1970s.
The report issues yet another warning. This is for people living in mountainous regions. Heat waves, glacial retreats and permafrost degradation may lead to hazards like glacial lake outburst floods and landslides.
| Megacities in danger
The 2005 floods in Mumbai were unprecedented. Within 24 hours the city received 94 cm of rainfall. About 1,000 people, most living in slums, died. Business was severely hit with communication, electricity and transportation completely paralysed for days. This forced IPCC to name Mumbai as the city with the highest population exposed to coastal flooding. At present, about 2.8 million people and about US $46 billion worth assets are exposed to coastal flooding. By 2070, the exposed population will increase to 11 million people and exposed assets to about US $1.6 trillion.
Mumbai epitomises the dangers megacities on coasts face. In this case, adaptation is difficult because most of the infrastructure development has taken place in the past 150 years, and not planned to tackle climate change induced weather changes. This makes slum-dwellers extremely vulnerable as even a 50 cm rise in sea level could wipe out settlements. Other cities that the IPCC report names are Kolkata, Dhaka, Guangzhou, Ho Chi Minh City, Shanghai, Bangkok, Rangoon, Hai Phong and Miami. All except Miami are in developing countries. About 1.3 to 1.4 billion urban poor lay exposed to sea level rise and they are overwhelmingly in developing countries.