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Title:	The characteristics of climate extremes over Indonesia: past trends, responses to ENSO and their future projection under anthropogenic climate change
Authors:	Supari (P74778)
Supervisor:	Fredolin Tangang, Prof. Dr.
Keywords:	Climatic extremes Climatic changes Universiti Kebangsaan Malaysia -- Dissertations Dissertations, Academic -- Malaysia
Issue Date:	2-Nov-2019
Description:	This thesis documents the characteristics of climate extremes and their changes over Indonesia in relation with climate variability (i.e. El Niño Southern Oscillation (ENSO)) and anthropogenic climate change. The objectives of this study include: (i) to investigate the past characteristics of climate extremes (ii) to characterize the responses of precipitation extremes to the ENSO and (iii) to estimate the future changes of precipitation extremes over Indonesia associated with anthropogenic warming. Various data were used in this study including 33 years of daily observed station rainfall and temperature data, gridded Sea Surface Temperature (SST), NCEP/NOAA Reanalysis data and the multi-model simulations product of the Southeast Asia Regional Climate Downscaling/Coordinated Regional Climate Downscaling Experiment –Southeast Asia (SEACLID/CORDEX-SEA). Changes of past climate extremes were investigated using spatio-temporal trend analysis while their changes related to ENSO were studied using composite analysis. Projected changes of climate extremes were analysed for three time windows i.e. early-century (2016-2035), mid-century (2046-2065) and late-century (1981-2100) with respect to reference period (1986-2005). A subset of extreme indices recommended by the Expert Team on Climate Change Detection and Indices (ETCCDI) was used to represent duration, frequency and intensity of climate extremes. The results showed that, during the last three decades, significant and spatially coherent trends of warming in the temperature extreme indices were observed over Indonesia. Averaged over the country, the annual mean of daily maximum (TXmean) and minimum temperature (TNmean) had increased significantly by 0.18 °C and 0.30 °C per decade, respectively. In contrast, trends in the precipitation extremes indices were generally not significant and less spatially coherent. Only one extreme index (SDII, Simple Daily Intensity Index) shows a significant increasing trend i.e. by 0.21 mm/day per decade. During ENSO events, this study found that anomalies in the duration of extremes (i.e. consecutive dry days (CDD) and consecutive wet days (CWD)) were much more robust than in the seasonal rainfall. El Niño generally associates with dry condition over Indonesia, particularly during June-July-August (JJA) and September-October-November (SON) seasons where extreme indices register anomalous values of more than 40%. On the other hand, La Niña induced condition over Indonesia is rather opposite to that of El Niño. However, starting from December-January-February/DJF (SON) an opposite response was observed over Sumatra during El Niño (La Niña) and expanded eastward to create a contrast in the pattern of ENSO impact between western and eastern part of the country. This eastward expansion was mainly controlled by dynamic of regional ocean-atmosphere coupling. In the future, the precipitation extremes are projected to intensify, with more significant and robust changes by the late-century, than in early and mid-century, for middle and high-end emission scenarios. The most significant and robust projected change is the intensification of dryness over Indonesia during June to November as indicated by the increase in CDD by as much as 50% relatively the climatology. The key findings of this study suggested that a combined effect of climate variability (El Niño) and anthropogenic climate change would steer Indonesian region to be much drier condition from June to November in future period than what was experienced under El Niño condition alone in the past.,��Certification of Master's/Doctoral Thesis�� is not available,Ph.D.
Pages:	192
Call Number:	QC981.8.C53S797 2019 tesis
Publisher:	UKM, Bangi
Appears in Collections:	Faculty of Science and Technology / Fakulti Sains dan Teknologi

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