Drought monitoring techniques for climate change in the Northern part of Thailand

Abstract

Occurrence of drought is due to climate variability and climate change. Drought affected on agriculture, economic, social and environment. The suitable technique in detecting and monitoring drought events can provide useful information for prevention and mitigation planning from their impacts. The study objective was to investigate the change of rainfall and temperate as well as find out the appropriate drought index and its trend for the Northern part of Thailand. These drought indices were calculated by using meteorological data during 1951-2020 of 10 stations comparing with historical drought records between January and May during 2011-2016 in the same areas. The drought indices consisted of Standardized Precipitation Index (SPI), Deciles index and Moisture Available index (MAI) at 1-, 3- and 6-month timescales and Palmer Drought Severity Index (PDSI). It was found that PDSI was the most appropriate index. The Mann-Kendal test was used to investigate the trend of rainfall, temperature and PDSI. The results showed an increasing of temperature. There was no trend of drought intensity for long-term (40 years) periods but was in 4 stations for short-term (20 years) periods. The PDSI can be used for drought monitoring and predicting in advance by using numerical weather prediction products.