As the world continues to pump greenhouse gases into the atmosphere, the global temperatures could rise by 3°C by mid-century, says a soon-to-be-released report of the Intergovernmental …
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.
6 Hurricane Ivan hit the Caribbean (2004)
7 Unofficially named Catarina, the hurricane developed in South Atlantic Ocean. It made landfall along southern coast of Brazil (2004)
8 Warmest summer in central Canada (2005)
9 Worst drought in 60 years in Brazil led to the lowest flow in Amazon in 30 years (2005)
11 Hurricane Katrina hit southern US, killing more than 1,300 people (2005)
14 Severe to extreme drought in western and southern plains of America (2006–2007)
16 Coldest winter in 50 years, unusual snowfall in southern South America (2007)
17 Massive floods in Mexico, considered the worst weather-related disaster in the nation’s history (2007)
22 Severe, prolonged drought hit Argentina, Uruguay, Paraguay and southern Brazil, causing severe damage to agriculture, livestock and water resources (2008)
23 Several all-time winter snowfall records set across Canada (2008)
27 Exceptional heatwave in north and central Argentina had record-breaking temperatures of more than 40°C in large areas (2009)
29 Extreme cold wave and record snowfall during winter in large parts of United States and Europe (2009-10)
36 A spate of tornadoes hit south-eastern United States, killing over 300 people (2011)
39 A severe thunderstorm inflicted significant damage to property in Toronto (2011)
40 A historic blizzard brought heavy snowfall and cold air to New Mexico, New England, Texas and parts of Canada. It left around 25 people dead (2011)
AFRICA & WEST ASIA
2 Heavy rainfall and floods hit Mozambique, Zimbabwe, Malawi and Zambia between February and April (2001)
5 Tropical cyclone Gafilo hit Madagascar with winds up to 260 km per hour, causing hundreds of deaths (2004)
13 Long-term drought continues over the Greater Horn of Africa (2006)
18 Heavy rainfall caused floods and flash floods in several African countries. Thousands of homes were destroyed and more than 1.5 million people affected (2007)
19 Tropical cyclone Gonu formed in the north Indian Ocean, making landfall in Oman and then reaching the Islamic Republic of Iran. It was reported as the strongest cyclone on record in the Arabian Sea (2007)
24 Heavy and extended rainfall affected Algeria and Morocco during September–November, causing infrastructure damage. These were the worst floods in a century for Algeria. A similar meteorological situation was repeated a year later in the same region (2008)
33 Extreme precipitation events occurred in West Africa with the worst floods in 50 years in Benin (2010)
1 Extreme cold winter in Siberia and Mongolia. Minimum temperatures dropped to near -60°C across central and southern Siberia resulting in hundreds of deaths (2001)
4 Unprecedented extreme heatwaves across Europe during summer. This led to record-breaking temperatures, surpassing 40°C in some cases and many thousand related deaths (2003)
15 In July, extreme rainfall triggered the worst floods in 60 years over the United Kingdom (2007)
20 A remarkably mild winter occurred over most parts of Scandinavia. With monthly anomalies exceeding 7°C, large parts of Norway, Sweden and Finland had the warmest winter ever recorded (2008)
30 Extreme heat and drought in July and August led to disastrous bushfires in western part of Russian Federation (2010)
34 Floods affected central and eastern Europe several times in the past decade. Poland was most affected in 2001, while Germany, Romania, Austria, Czech Republic and Slovakia were affected in 2002, with thousands of people evacuated. In 2008, Germany was hit by a large number of thunderstorms with hail and tornadoes. In 2009, some countries suffered floods similar to those observed in 2002. In 2010, floods in the Danube river basin caused severe damage (2001–2010)
ASIA & AUSTRALIA
3 Typhoon Rusa caused floods and hundreds of deaths in Korea. It was reported the worst national storm since 1959 (2002)
10 Monsoon season brought unprecedented rainfall and floods to western and southern India, affecting more than 20 million people (2005)
12 Typhoon Durian hit the Philippines, causing massive damage and more than a thousand deaths (2006)
21 Extreme cold temperature combined with the worst snowstorm in five decades across China. Extreme cold event extended as far west as Turkey (2008)
25 In southern Australia, dry conditions reinforced long-term drought. These exacerbated water shortages in Murray-Darling Basin, resulting in crop failure (2008–2009)
26 Tropical cyclone Nargis was the worst natural disaster to hit Myanmar. It killed more than 70,000 people (2008)
28 Record heatwaves across Australia. Disastrous associated bushfires caused more than 170 fatalities. The highest temperature ever recorded so far south in the world was observed in Victoria with 48.8°C (2009)
31 Pakistan experienced the worst floods in its history. More than 1,700 deaths were reported (2010)
32 Heavy rainfall in China contributed to floods and landslides, including a devastating mud-rockslide that killed more than 1,500 people in north-west China (2010)
35 Australia faced its worst flood in about 50 years. It submerged or disrupted life across an area the size of France and Germany combined (2010)
37 Thailand and Cambodia experienced one of the worst floods in recent history killing 800 people (2011)
38 Odisha, Gujarat and Uttar Pradesh ravaged by floods. It left about 300 people dead and seven million affected (2011)
| Workforce hit
Heat is taking its toll on India’s workforce, research indicates. As part of its preliminary work on the relationship between heat stress and productivity, scientists at the Indian Institute of Technology-Delhi have attempted to look into the relationship between working hours and rise in temperature.
Heat stress, which is caused when the body becomes overheated, reduces work capacity, as employees take frequent breaks to recover from exhaustion.
S K Dash, professor at the Centre for Atmospheric Sciences, IIT-Delhi and his colleague T Kjellstrom from the National Centre for Epidemiology and Population Health, Australian National University, Canberra, looked at historical data on the number of workable hours during June, the hottest month in Delhi. He found that the number of workable days had steadily reduced between 1960 and 2000. For example, between 1960 and 1979, an individual involved in serious labour, like construction work, would have worked only four days in June without taking a break due to exhaustion. Today, that number is reduced by half.
At present, the Wet Bulb Globe Temperature (WBGT) is the internationally accepted standard for occupational heat stress and is used to quantify the need for rest breaks in different work situations, with the aim of keeping the core body temperature below 38ºC. The number of workable days in Dash's study was calculated using WBGT. However, this is not a suitable for India because of its complex climate.
Dash wants to create a comprehensive formula specifically for India to calculate heat stress. This will help quantify the impact of heat on employees across several sectors.