Siam (Thailand) Climate

By | December 17, 2021

During the sec. XVIII very little could be added to the knowledge that already existed. Among the explorations of the century. XIX are those of the Englishman D. Richardson, who in 1839 crossed the mountains of Tenasserim between Moulmein and Kanchanaburi; of the French botanist H. Mouhot, who from Menam went to Korat and then to Pak Lay and Luang Prabang, where he died (1861); of Sir Robert Schomburgk, English consul in Bangkok, who in 1860 went up the Menam and Me Ping, reached Chiengmai, then, through the mountains, Moulmein, and then returned to Bangkok via Kanchanaburi; by the Frenchman A. Pavie, who visited southern Siam in 1879 and between 1880 and 1885 made various other trips to Siam and Cambodia. The exploration and survey work carried out at the end of the 19th century (1881-1893) by the Englishman J. Mc Carthy, who was in the service of the Siamese government for ten years. He visited almost the whole country, of which he also prepared a valuable map. He was responsible for the constitution of theSiamese Survey Department. Among the explorers and scientists who visited Siam in the century XX are to be remembered F. Lupša, CC Hosseus, JP Andersen, LJ Robbins and above all W. Credner, who from November 1927 to March 1929 traveled the country in every sense, collecting a huge harvest of observations. For Thailand 2000, please check

Climate. – Siam has notably different climatic conditions between one part and the other, mainly due to the direction of the mountain ranges with respect to the breath of the SW monsoon, on which the trend of temperatures and that of precipitation depend. The highest temperatures (29-30 ° in central Siam) occur in April or May, depending on the beginning of the rainy period of the SW monsoon, during which the lesser amount of sunshine decreases temperatures a little. The daytime excursion is 12-13 ° in the warmer months, 7-8 ° in the cooler ones (October-February); the annual excursion is only 2-3 ° in central Siam, but rises to 7-8 ° in the valleys of the mountainous northern Siam. Precipitation is abundant especially in the peninsular part, and particularly on the western side of it, where annual maximums of over 4 m are also reached. (Takuapa, 4298 mm.), But they usually occur on 2 meters. They are included within the isoieties of 2000-3000 mm. also the eastern slopes of the Tenasserim ranges (the western ones receive more than 3000 mm of rain everywhere), a stretch of the SE Siam coast, on the border with Cambodia, and part of the Pnom Dang Rek mountains. The monsoon of SW., Emaciated by these mountain screens, reaches much less humid on northern and central Siam, which in the majority is included between the isoieta of 1000 and that of 1500 mm. The eastern Siam in the center also falls within the 1000 and 1500 mm isoieties; at the edges, on the other hand, due to the hills that close it, it is more rainy (1500-2000 mm). It should be noted that there are some restricted areas of central and eastern Siam where rainfall appears to be less than 1000 mm. nodded. The rainy season usually runs from April to October (in northern Siam it is shorter: May-September).

To continental waters. – Most of the Siamese territory is divided between the Menam and Mekong basins. The Menam, which flows into the Gulf of Siam after a course of 700 km., Has its spring branches, as we have seen, in northern Siam: the Menam Nan and the Me Ping, the main among these, join at Nagor Svarga, and from here the Menam (properly Menam Chau Phaya) begins to be navigable by vaporetti. Downstream from Nagor Svarga begins the delta, flat and elongated, crossed by various arms of the river and a network of artificial canals (klong) which serve to irrigate the rice fields during the dry period. The lower Menam is in flood from May to November and then it floods the lower plain on about 31,000 sq km.

The Mekong, as mentioned, marks the border between Siam and French Indochina for a long stretch; of the numerous tributaries that flow in Siamese territory the most notable is the Nam Mun, whose extensive system drains a large part of the Korat plateau.

Of the other Siamese rivers it is worth mentioning the Meklong (400 km.), Which originates in the mountains of Tenasserim and flows into the Gulf of Siam to the west of the Menam.

Among the lake basins, the coastal one of Tale Sap, in the Malay Peninsula, with fish-rich waters, is noteworthy.

Siam (Thailand) Climate