07. Climate characteristics and changes in Tho Chu archipelago in the early 21st century

Abstract

Climate in the Tho Chu archipelago in the early 21^st century showed that the prevailing wind direction was East and Northeast in dry season and West and Southwest in rainy season. The main wind speed was level 2 and had been reducing by 0.1m/s annually. The average air temperature was 27,6 ^oC and it is “warmer” with the average temperature increased by 0,032 ^oC/year. Air humidity ranged from 37,5 % - 99,0 %. The average air humidity was about 84 % from June to October and 80 % from December to April next year. Humidity tends to decrease 0,01 %/year. The average air pressure was 1009,9hpa and had an average cycle of 4 - 7 years. The pressure was high in winter and low in summer. There was a slightly increase in pressure with an average increase of 0,02 hpa/year. Total annual rainfall ranged at 1,396 mm - 2,891 mm and the number of rainy days ranged from 200 to 260 days. The number of rainy days and heavy rain days were mainly from May to November. Heavy rainfall was mainly from June to October. Rainy days and rainfall in Tho Chu archipelago had been decreasing gradually with the average amount of rainfall reduction of 21 mm per year.