Major Environmental Concerns  

[ Land | Forest | Biodiversity | Water | Marine & Coastal Environments | Urban & Industrial Environments ]

Underlying Causes

[ Social | Economic | Institutional | Environmental ]

Many of the developing countries in this region are situated in the world's hazard belts of floods, droughts, cyclones, earthquakes, windstorms, tidal waves, and landslides. The major natural disasters faced periodically are largely due to climatic and seismic factors. The region has been one of the worst hit in terms of natural disasters, suffering 50 per cent of the world's major emergencies (ESCAP, 1995a). Since the International Decade for Natural Disaster Reduction began in 1990, the total number of deaths in the region due to these causes has exceeded 200,000, with the damage to property over this period estimated at US$100 billion (ESCAP, 1995a). Vulnerability has increased due to growing urban populations, environmental degradation, and a lack of planning and preparedness.

Disasters are the result of meteorological phenomena such as typhoons, hurricanes, sheet flooding, and marine- and river-based floods; of geological processes such as volcanic eruptions, earthquakes, and tsunamis; and of climatic phenomenon such as the El Niño-Southern Oscillation that results in a lower mean sea surface temperature in the east, failure of the monsoon rains in India, and drought in Indonesia and Australia. Vulnerability to natural hazards has been increased in many coastal areas due to the loss of habitats such as mangroves and coral reefs that provided natural protection against marine-based flooding.

Tropical cyclones, or typhoons, which are common in Asia and the Pacific, occur most frequently over the north-west Pacific during June and November just east of the Philippines , with an average of 30 typhoons per year (38 per cent of the world's total) (ESCAP, 1995a). In the Bay of Bengal, tropical cyclones usually form over the southern end during April-December and then move to the east coast of India and Bangladesh, causing severe flooding and, often, devastating tidal surges. The cyclones generated in the South Pacific Ocean frequently cause devastation in small island countries such as Fiji, Tonga, Vanuatu, Solomon Islands, and Samoa. Overall, the Philippines , Bangladesh , and Vietnam appear to suffer most frequently from these large events.

Floods, which are the most common climate-related disasters in the region, include seasonal flooding, flash flooding, urban flooding due to inadequate drainage facilities, floods associated with tidal events induced by typhoons in coastal areas, and so on. In Bangladesh , one of the most flood-prone countries in the region, as many as 80 million people are vulnerable to flooding each year (ESCAP, 1995a). Another example is India , where 40 million hectares are at risk from flooding each year, and the average annual direct damage has been estimated at US$240 million, although this can exceed US$1.5 billion when flooding is severe (ESCAP, 1995a).

It has been observed that the impact of droughts differs widely between industrial and developing countries because of such factors as water supply efficiency and behavioural patterns such as water use efficiency. Most of the estimated 500 million rural poor in this region are subsistence farmers occupying mainly rainfed land (ESCAP, 1995a). The drought-prone countries in this region are Afghanistan , Iran , Myanmar , Pakistan , Nepal , India , Sri Lanka , and parts of Bangladesh . In India about 33 per cent of the arable land-14 per cent of the total land area of the country-is considered to be drought-prone, and a further 35 per cent can also be affected by drought when rainfall is exceptionally low for extended periods (ESCAP, 1995a). Nepal has experienced severe droughts in the past. Also, the Philippines , Thailand , Australia , and the Pacific islands of Fiji , Vanuatu , and Samoa contain drought-prone areas.

Landslides, which are very common in the hills and mountainous parts of the region, occur frequently in India , China , Nepal , Thailand , and the Philippines . In addition to the primary cause-the topography-landslides are aggravated by human activities, such as deforestation, cultivation, and construction, which destabilize the already fragile slopes. For instance, as a result of combined actions of natural (mostly heavy rainfall) and human factors, as many as 12,000 landslides occur in Nepal each year (ESCAP, 1995a).

The region has recorded 70 per cent of the world's earthquakes measuring 7 or more on the Richter scale, at an average rate of 15 per year (ESCAP, 1995a). The countries badly affected by earthquakes include Afghanistan , India , Iran , Japan , Nepal , the Philippines , and the Pacific Islands .

Many of the countries in the region are located along or adjacent to the Pacific Ocean Seismic Zone and/or the Indian Ocean Seismic Zone. For instance, 50-60 per cent of India is vulnerable to seismic activities of varying intensity (ESCAP, 1995a). These areas are essentially located in the Himalayan region and in the Union Territory of the Andaman and Nicobar Islands . The September 1993 earthquake in Maharashtra State in Western India claimed more than 12,000 lives (ESCAP, 1995a).

Similarly, about 80 per cent of China 's territorial area (with 60 per cent of its large cities and 70 per cent of its urban areas with populations over 1 million) is located in seismic zones (ESCAP, 1995a). The most devastating earthquake in the world in recent history, the Tangshan earthquake in China on 28 July 1976 , claimed more than 240,000 lives (ESCAP, 1995a). Japan is located in the Pacific Rim seismic zone.

Japan suffers a massive earthquake (Richter scale 8 or over) on average once every 10 years, and a large-scale earthquake (magnitude 7 class) on average once a year (ESCAP, 1995a). In January 1995, Japan suffered one of the worst earthquakes in recent years at Kobe , which claimed 5,000 lives (ESCAP, 1995a). The Philippines , which lies between two of the world's most active tectonic plates, experiences an average of five earthquakes a day, most of which are imperceptible (ESCAP, 1995a). And in New Zealand , an average of 200 perceptible earthquakes occur each year, with one at least exceeding 6 on the Richter scale (ESCAP, 1995a).

Tsunamis, the tidal waves generated by earthquakes, affect many of the coastal areas of the region, including those of Japan , Indonesia , and the Philippines . For example, the infamous Krakatau volcanic eruption during 1883 in Sunda Straits , Indonesia , generated a 35-metre-high tsunami, which claimed 36,000 lives (ESCAP, 1995a). Furthermore, the tsunami of 17 August 1976 in the Moro Gulf area of the Philippines caused some 8,000 deaths (ESCAP, 1995a).

Volcanoes, like earthquakes, are located mainly along the Pacific Rim . Countries of the region at risk from volcanic eruptions include Indonesia , Japan , New Zealand , Papua New Guinea , the Philippines , Solomon Islands , Tonga , and Vanuatu . Those most frequently affected are Indonesia (129 active volcanoes), Japan (77 active volcanoes), and the Philippines (21 active volcanoes) (ESCAP, 1995a; Government of Japan, 1987).

Notable examples include the eruptions of Mount Pinatubo in Central Luzon, during the period 12-15 June 1991, which affected about 1-2 million people (Lewinson, 1993), demolished the surrounding forests, caused massive siltation of rivers and coastal areas, and deposited volcanic ash in surrounding areas and even across continents. In New Zealand , Mount Tarawera had a severe eruption in 1886, and the Ngauruhoe, which erupted in 1974, emits steam and vapour constantly (ESCAP, 1995a). In Papua New Guinea , the volcanic eruption in 1994 near the city of Rabaul damaged about 40 per cent of the houses in the area (ESCAP, 1995a).

Environmental degradation and disasters are very closely linked in this region. The countries that suffer most from disasters are the same ones in which environmental degradation is proceeding most rapidly. Similarly, poverty and vulnerability to disasters are closely linked. There are some 3,000 deaths per event in low-income countries, and less than 400 per event in middle- and high-income countries (ESCAP, 1992). This reflects the absence of a sufficient infrastructure in low-income economies to mitigate the impact of natural disasters. Both Japan and Pakistan are prone to earthquakes, for example. The people of Japan , however, are far less vulnerable because that Government has strictly enforced building codes, zoning regulations, and earthquake emergency training and communication systems; in Pakistan , most people still live in top-heavy mud and stone houses built on hillsides, increasing their vulnerability.

United Nations Environment Programme