Thailand covers an area of 514,000 square kilometres in the centre of the South-East Asian peninsula. It is bordered by Myanmar (Burma), Lao People’s Democratic Republic, Cambodia and Malaysia, and has 2,420 kilometres of coast line on the Gulf of Thailand and the Andaman sea. Thailand stretches 1,650 kilometres from north to south, and from east to west 780 kilometres at its widest point.
For economic, social and ecological reasons, Thailand is usually classified into four geographical regions. They are: the central region (including Bangkok Metropolitan Region) comprising the basin of the Chao Phrya River which runs from north to south and after crossing Bangkok flows to the Gulf of Thailand. The central region is often called the “rice bowl” of Thailand being the most fertile area of the country. After the Bangkok Metropolitan Region, it enjoys the highest per capita income in the country.
The northern region is mountainous and was traditionally the most heavily forested area of the country. In the recent years, however, overcutting has considerably reduced its forest resources. The main centres of population are in the narrow alluvial valleys along the four north-south flowing rivers which unite in the northern central plain to form the Chao Phraya.
The north-eastern region (Isarn) constitutes approximately one third of the area of the Kingdom and comprises the Korat Plateau which is bounded on the north and east by the Mekong River and the south by the Dongrek escarpment. The region is drained by the Mun and Chi rivers, both tributaries of the Mekong. Largely owing to lower and erratic rainfall and poorer soils than in other parts of the country, the north-eastern provinces have the lowest per capita income in the country.
Approximately one third of the population of Thailand lives in the north-east. The south-eastern region: the south-east, which comprises the hilly countryside from Bangkok to the Cambodian border, is characterized by higher rainfall and poorer soils than the adjoining central region. It is an important fruit, maize and cassava-growing area and its coastline offers extensive opportunities for fisheries and tourism. The high rainfall also permits some rubber to be grown.
The southern region: the southern peninsula has the highest rainfall in the country. It is the principal rubber-growing area and contains extensive alluvial deposits of tin. The forests of the south have been seriously overcut as elsewhere in the Kingdom. In recent years, the region has suffered from severe floodings which are believed to have been amplified by deforestation and subsequent soil erosion.
Located outside the typhoon belt, Thailand can be divided into two climatic zones. The north, north-east, south-east and central regions including Bangkok have a climate with three distinct seasons: rainy, from June to October; cool, from November to February; and hot of highest temperatures and sunny weathers from March to May.
Temperatures in Bangkok vary between 20 C in December and 38 C in April with an average humidity of 82 percent. Winter temperatures in the north can fall to approximately 10 C or lower. The average rainfall in these regions is 1,250 cms per year.
The southern region has a characteristic tropical rainforest climate. Rainfall occurs virtually throughout the year, although a number of micro-climates can be found. There is little variation in temperature, which is on average 28 C throughout the year. March and April are normally the driest months in the south. The periods of maximum rainfall in these areas vary according to climatic sub-regions.