[12], a research to improve global gridded dataset of extreme indices (HadEX to HadEX2, [10]), showed widespread significant changes in temperature extremes with warming especially for those indices derived from minimum temperature. Agricultural Development A statistical downscaling tool is employed to downscale GCM outputs. In Southeast Asia, mean warming of temperature will be 2.5°C in 2080–2099 relative to 1980–1999 [55]. The black solid is representing the 5-year moving average of anomalies. In mountainous provinces like Chiang Rai and Chiang Mai, the temperature is observed to be higher than other provinces. However, monthly maximum and minimum temperature will boost up by 1.56 and 2.24°C at the end of this century as compared to the 2020s.

Both of these indices are projected to increase significantly. It is nearly as powerful as its parametric competitors. Both models showed higher accuracy in case of predicting the rainfall compared to the base period. Along with greater risks of flooding, higher temperatures may also increase malnutrition in the nation. With much of the economy relying on agriculture and natural resources for income, climate change in Thailand has critically affected the productivity and development of the nation. Therefore, these issues can be addressed by downscaling approaches.

C. Tebaldi, K. Hayhoe, J. M. Arblaster, and G. A. Meehl, “Going to the extremes—an intercomparison of model-simulated historical and future changes in extreme events,”, J. Alcamo, N. Dronin, M. Endejan, G. Golubev, and A. Kirilenko, “A new assessment of climate change impacts on food production shortfalls and water availability in Russia,”, R. P. Allan and B. J. Soden, “Atmospheric warming and the amplification of precipitation extremes,”, J. H. Christensen, B. Hewitson, A. Busuioc et al., “Regional climate projections,” in, H. Kettle and R. Thompson, “Statistical downscaling in European mountains. Different significant levels (10%, 5%, 1%, and 0.1%) were used to consider a trend to be statistically significant. Therefore, in this study, observed trends in temperature and rainfall extremes in North Thailand were investigated over the last 51 years. All of the extreme indices (13 for temperature and 11 for rainfall, Table 2) are calculated from the daily observation of temperature and rainfall by using RClimDex software [40]. [52] reported decreasing trend of the diurnal temperature range (DTR) because of rapid increase of the minimum temperature in recent decades. The trend of annual total rainfall (PRCPTOT) reveals a very high significant increasing trend except B2 scenario of PRECIS RCM. With much of the economy relying on agriculture and natural resources for income, climate change in Thailand has critically affected the productivity and development of the nation. While the challenges are acknowledged by the nation, solutions are being debated frequently. The SEA START RC used ECHAM4 GCM (resolution 280 × 280 km2; Max Plank Institute, Germany) for climate scenario generation and PRECIS RCM (developed at the Hadley Centre at the Meteorological Office, spatial resolution of 25 × 25 km2 and emission scenarios B1, B2, A2, and A1FI) for downscaling the GCM data for specific region. Review articles are excluded from this waiver policy. © 2020 Global Environment Facility, All Rights Reserved. Thailand is the world’s largest rice exporter, making agricultural output ten percent of the country’s GDP. Number of days with rainfall ≥10 mm (R10) and ≥20mm (R20) are indicators of moderate and heavy rainfall. The data were edited if the problem is obvious (e.g., negative precipitation, 195 degrees changed to 19.5, and maximum temperature less than minimum temperature), set to missing if it is clearly a problem with unknown solution, or kept if deemed probably valid. The WHO estimates that, if the current emissions standards remain, over 2.4 million citizens in Thailand will be affected by flooding from the sea. These issues constituted the motivation for this research. In future, the maximum temperature beyond 35°C (summer days) and minimum temperature beyond 25°C (tropical nights) will increase with the very high significant trend. This study analyzes 24 climate extreme indices over North Thailand using observed data for daily maximum and minimum temperatures and total daily rainfall for the 1960–2010 period, and HadCM3 Global Climate Model (GCM) and PRECIS Regional Climate Model simulated data for the 1960–2100 period.

The northern part of the country usually experiences an extended period of warm weather because of its inland nature and tropical latitude zone [29]. Temperature extreme indices showed a significant rising trend during the observed period and are expected to increase significantly with an increase in summer days and tropical nights in the future. Projected changes in precipitation and dryness extremes are more ambiguous than that in temperature extremes at the end of 21st century [11].

Daily minimum temperatures are projected to increase faster than daily maximum temperatures, leading to a decrease in diurnal temperature range in the world [55]. In this region, the average annual temperature ranges from 20 to 34°C and the average annual rainfall varies between 1000 and 1800 mm depending on the location. For the period 2011–2099, the HadCM3 GCM and PRECIS RCM models project increase in total annual rainfall by 20.95% and 18.46%, respectively, above the observed period mean of 1725 mm in Chiang Rai Province. Diurnal temperature range will go down (0.64°C) notably over the study area. For all SRES (A2 and B2) of both models considered in this study, the maximum and minimum temperature increases projected for the period of 2011–2099 were 0.99 and 0.93°C above the observed period. Administratively as well as geographically Thailand has four regions, namely, the Northeastern, North, Central Plain, and Southern. Location map of the study area in Thailand. This model becomes more accepted in recent years due to its applicability in a wide region and simplicity of establishing a relationship between predictor and predictand variables for future time zone [33]. However, the rainfall anomaly, regionally averaged, showed a continuous increasing trend of annual rainfall (Figure 7). The purpose of the study is not to find out the best climate model rather than identifying the past and future changes of climate extremes in the regional scale through different emission scenarios. Monthly indices of temperature and rainfall extremes for the observed period 1960 to 2010 averaged across the study area. The simple daily intensity index (SDII) is the combined effect of the trend of PRCPTOT and consecutive wet days (CWD).
Our analysis enables a number of conclusions to be drawn as follows:(1)During observed 1960–2010 period, the entire temperature extremes showed a warming trend which is also supported by the statistical analyses.

The increasing trend of summer days (SU35) and tropical nights (TR25) favored the increment of temperature in the study area except in Chiang Rai Province. Zhang et al. A2 is the future of the differentiated world, with emphasis on human wealth. HadCM3 was chosen for this analysis because it is one of four sets of climate model (HadCM2, HadCM3, CGCM2, and CSIRO) output provided with SDSM.

However, a statement by the World Health Organization says investment in the population’s health is likely to be threatened by climate change. However, in summer, the projection is opposite to spring where annual rainfall is increasing in 2020s, 2050s, and 2080s ranging from 19.83 to 46.55%. We are committed to sharing findings related to COVID-19 as quickly as possible. During the observed period, annual total rainfall (PRCPTOT) and moderate rainfall (R10) indices were decreased which is supported by the negative trend of consecutive wet days (CDD). By 2070 the WHO predicts that 71 million people in Thailand will be at risk for malaria if current climate changes persist. The RCM is essentially a numerical model in which GCMs are used to fix boundary conditions. Trend of temperature indices for 2011–2099 period in Chiang Rai. [10] showed that over 70% of global land area observed significant increase in the annual occurrence of warm nights and significant decrease in occurrence of cold nights.

Comparison of observed and simulated cumulative rainfall (a), monthly maximum temperature (b), and monthly minimum temperature (c) for 1980–1989 of Chiang Rai. The main reason to select PRECIS RCM in this research is that SEA START RC specially handles Southeast Asian region to predict more precise climate and freely provide data to researchers. “The Borgen Project is an incredible nonprofit organization that is addressing poverty and hunger and working towards ending them.”
However, a statement by the World Health Organization says investment in the … [13] revealed significant decrease in the number of rainy days, significant increase in the proportion of total rainfall from extreme rainfall, significant increase in the minimum and maximum temperature, increase in the number of warm nights, and decrease in the number of cold nights and cool days at Nan Province of North Thailand. However, the annual rainfall is projected to increase by 9.65% in the future 2011–2099 period compared to the observed 1960–2010 period. In contrast to summer days (SU35) and tropical nights (TR25), tropical nights will increase far beyond summer nights with the same level of significance.