Changes in temperature extremes and their relationship with ENSO in Malaysia from 1985 to 2018. (19th October 2020)

• Record Type: Journal Article
• Authors: Tan, Mou Leong; Juneng, Liew; Tangang, Fredolin T.; Chung, Jing Xiang; Radin Firdaus, R. B.
• Is Part Of: International journal of climatology. Volume 41(2021)Supplement 1
• Page Start: E2564
• Page End: E2580
• Publication Date: 2020-10-19
• Subjects: climate change -- ENSO -- ETCCDI -- extreme -- global warming -- Malaysia -- temperature -- trend analysis; Climatology -- Periodicals; Climat -- Périodiques; Climatologie -- Périodiques; 551.605
• DOI: 10.1002/joc.6864
• Languages: English
• ISSNs: 0899-8418

Abstract

Abstract: Understanding the changes in temperature extremes is important for managing and coping with the risks associated with regional climate change. However, the climatological characteristics of temperature extremes and their variabilities is still not adequately studies in Malaysia. This study evaluates the spatial and temporal variations of temperature extremes over Malaysia for the period 1985–2018. This study includes four phases: (a) collection, quality control and homogeneity analysis of temperature data; (b) general (TXmean, TNmean, TMmean and DTR), warm (TXx, TNx, TX90p and TN90p) and cool (TXn, TNn, TX10p and TN10p) temperature extreme indices calculations; (c) trend analysis of temperature extremes using the Mann‐Kendall and Sens's slope test; and (d) analyses of correlations between temperature extremes and El Niño‐Southern Oscillation (ENSO). The results indicate a warming of surface temperature across Malaysia, particularly in Peninsular Malaysia. In general, TXmean, TNmean and TMmean increased significantly at 5% significance level by 0.12°C/decade, 0.27°C/decade and 0.17°C/decade, respectively. A significant decreasing trend in DTR by 0.12°C/decade is seen, which is related to the higher increasing rate of TNmean. All of the warm extreme indices, TXx, TNx, TX90p and TN90p presents significant increasing trends by 0.19°C/decade, 0.28°C/decade, 2.86%/decade and 3.08%/decade, respectively. For the cool extreme indices, TX10p and TN10p decreased significantly by 0.95%/decade and 3.18%/decade, respectively, though the trend in TXn by 0.11°C/decade is not statistically significant. The only cool index presenting a significant increasing trend is TNn by 0.44°C/decade, indicating a reduction of cool nights. Besides that, major cities in the northern and western parts of Peninsular Malaysia generally exhibit a higher warming trend compared to rural and highland area. These are possibly related to the intensified urban heat island effect under the rapid urbanization. This study also found that the ENSO affected warm extreme indices much stronger than cool extreme indices in Malaysia. Abstract : The findings indicated a robust evidence of warming across Malaysia, particularly Peninsular Malaysia. In general, the average annual average maximum (TXmean), minimum (TNmean) and mean (TMmean) temperatures increased significantly at 5% significance level by 0.12°C/decade, 0.27°C/decade and 0.17°C/decade, respectively. Therefore, the diurnal temperature range (DTR) had a significant decreasing trend of 0.12°C/decade due to the higher increasing rate of TNmean.