Köppen-Geiger climate system classification and forecasting in Thailand

Anotace: Köppen-Geiger Climate Classification system (KGC) is one of well-known climate classification method with only rainfall and temperature values. This study aims 1) to update current total monthly rainfall, average monthly temperature and KGC map of 1987 – 2019 period and 2) to predict total monthly rainfall, average monthly temperature and KGC map of 2020 – 2060 and 2061 - 2100 period. The study was extracted by gathering total monthly rainfall and average monthly temperature from 104 meteorological stations over Thailand then cooperated with GIS process to classify and present climate type of 1987 – 2019. Moreover, Beijing Climate Center Climate System Model version 1.1 (BCC-CSM1.1) was used to forecast rainfall and temperature value to determine climate zone of Thailand of 2020 – 2060 and 2061 – 2100 period. The results of present period illustrated that Thailand climate was classified into three types: dry-winter characteristics (Aw) as a major climate, following by Tropical monsoon climate (Am) and Dry-winter humid subtropical climate (Cwa). In contrast, predicted values displayed only “Aw” and “Am” appearing in the mid and late twenty-first century, respectively. “Aw” climate covered the most area of Thailand with 90.14%, 91.85% and 96.37% while “Am” climate covered 8.77%, 8.15% and 3.63% for present, mid, and late twenty-first centuries period, respectively of a small area of Eastern part and almost half Southern region. Furthermore, “Am” climate was also predicted to appear in east side of Northeast region in 2020 - 2060 period whereas “Cwa” was appeared in small area of Northern region in 1987 – 2019 period. The up-to-date maps of rainfall, temperature value and KGC zone can be evidences to remind about climate change and support the future work.