Asia is the world’s largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth’s total surface area and comprises 30% of its land area. With approximately 4.3 billion people, it hosts 60% of the world’s current human population. Asia has a high growth rate in the modern era. For instance, during the 20th century, Asia’s population nearly quadrupled.
The boundaries of Asia are culturally determined, as there is no clear geographical separation between it and Europe, which together form one continuous landmass called Eurasia. The most commonly accepted boundaries place Asia to the east of the Suez Canal, the Ural River, and the Ural Mountains, and south of the Caucasus Mountains (or the Kuma–Manych Depression) and the Caspian and Black Seas. It is bounded on the east by the Pacific Ocean, on the south by the Indian Ocean and on the north by the Arctic Ocean.
Given its size and diversity, the concept of Asia – a name dating back to classical antiquity – may actually have more to do with human geography than physical geography. Asia varies greatly across and within its regions with regard to ethnic groups, cultures, environments, economics, historical ties and government systems.
Geography and climate.
Asia is the largest continent on Earth. It covers 8.8% of the Earth’s total surface area (or 30% of its land area), and has the largest coastline, at 62,800 kilometres (39,022 mi). Asia is generally defined as comprising the eastern four-fifths of Eurasia. It is located to the east of the Suez Canal and the Ural Mountains, and south of the Caucasus Mountains (or the Kuma–Manych Depression) and the Caspian and Black Seas. It is bounded on the east by the Pacific Ocean, on the south by the Indian Ocean and on the north by the Arctic Ocean. Asia is subdivided into 48 countries, two of them (Russiaand Turkey) having part of their land in Europe.
Asia has extremely diverse climates and geographic features. Climates range from arctic and subarctic in Siberia to tropical in southern India and Southeast Asia. It is moist across southeast sections, and dry across much of the interior. Some of the largest daily temperature ranges on Earth occur in western sections of Asia. The monsoon circulation dominates across southern and eastern sections, due to the presence of the Himalayas forcing the formation of a thermal low which draws in moisture during the summer. Southwestern sections of the continent are hot. Siberia is one of the coldest places in the Northern Hemisphere, and can act as a source of arctic air masses for North America. The most active place on Earth for tropical cyclone activity lies northeast of the Philippines and south of Japan.
The Gobi Desert is in Mongolia and the Arabian Desert stretches across much of the Middle East. The Yangtze River in China is the longest river in the continent. The Himalayas between Nepal and China is the tallest mountain range in the world. Tropical rainforests stretch across much of southern Asia and coniferous and deciduous forests lie farther north.
A survey carried out in 2010 by global risk analysis firm Maplecroft identified 16 countries that are extremely vulnerable to climate change. Each nation’s vulnerability was calculated using 42 socio, economic and environmental indicators, which identified the likely climate change impacts during the next 30 years. The Asian countries of Bangladesh, India, Vietnam, Thailand, Pakistanand Sri Lanka were among the 16 countries facing extreme risk from climate change.
Some shifts are already occurring. For example, in tropical parts of India with a semi-arid climate, the temperature increased by 0.4°C between 1901 and 2003. A 2013 study by ICRISAT aimed to find science-based, pro-poor approaches and techniques that would enable Asia’s agricultural systems to cope with climate change, while benefitting poor and vulnerable farmers. The study’s recommendations ranged from improving the use of climate information in local planning and strengthening weather-based agro-advisory services, to stimulating diversification of rural household incomes and providing incentives to farmers to adopt natural resource conservation measures to enhance forest cover, replenish groundwater and use renewable energy.
East Asia had by far the strongest overall Human Development Index (HDI) improvement of any region in the world, nearly doubling average HDI attainment over the past 40 years, according to the report’s analysis of health, education and income data. China, the second highest achiever in the world in terms of HDI improvement since 1970, is the only country on the “Top 10 Movers” list due to income rather than health or education achievements. Its per capita income increased a stunning 21-fold over the last four decades, also lifting hundreds of millions out of income poverty. Yet it was not among the region’s top performers in improving school enrolment and life expectancy.
Nepal, a South Asian country, emerges as one of the world’s fastest movers since 1970 mainly due to health and education achievements. Its presentlife expectancy is 25 years longer than in the 1970s. More than four of every five children of school age in Nepal now attend primary school, compared to just one in five 40 years ago.
Japan and South Korea ranked highest among the countries grouped on the HDI (number 11 and 12 in the world, which are in the “very high human development” category), followed by Hong Kong (21) and Singapore (27). Afghanistan (155) ranked lowest amongst Asian countries out of the 169 countries assessed.