Sains Malaysiana 47(1)(2018): 77–84

http://dx.doi.org/10.17576/jsm-2018-4701-09

Evaluation of Climate Variability Performances using Statistical Climate Models

(Penilaian Prestasi Kebolehubahan Iklim menggunakan Model Statistik Iklim)

NURUL NADRAH AQILAH TUKIMAT^1,2*, AHMAD SAIFUDDIN OTHMAN¹, SAFFUAN WAN AHMAD^1,2 & KHAIRUNISA MUTHUSAMY^1,2

¹Faculty of Civil Engineering & Earth Resources, Universiti Malaysia Pahang, 26300 Kuantan, Pahang Darul Makmur, Malaysia

²Centre for Earth Resources Research & Management (CERRM), Universiti Malaysia Pahang, 26300 Kuantan, Pahang Darul Makmur, Malaysia

Diserahkan: 16 Februari 2017/Diterima: 30 Jun 2017

ABSTRACT

Uncertainty of the climates nowadays bring the crucial calamities problems especially at unexpected areas and in anytime. Thus, the projection of climate variability becomes significant information especially in the designing, planning and managing of water resources and hydrological systems. Numerous climate models with varies methods and purposes have been developed to generate the local weather scenarios with considered the greenhouse gasses (GHGs) effect provided by General Circulation Models (GCMs). However, the accuracy and suitability of each climate models are depending on the atmospheric characters’ selection and the variables consideration to form the statistical equation of local-global weather relationship. In this study, there are two well-known statistical climate models were considered; Lars-WG and SDSM models represent for the regression and weather typing methods, respectively. The main aim was to evaluate the performances among these climate models suit for the Pahang climate variability for the upcoming year Δ2050. The findings proved the Lars-WG as a reliable climate modelling with undemanding data sources and use simpler analysis method compared to the SDSM. It is able to produce better rainfall simulated results with lesser %MAE and higher R value close to 1.0. However, the SDSM lead in the temperature simulation with considered the most influenced meteorological parameters in the analysis. In year Δ2050, the temperature is expected to rise achieving 35°C. The rainfall projection results provided by these models are not consistent whereby it is expecting to increase 2.6% by SDSM and reduce 1.0% by Lars-WG from the historical trend and concentrated on Nov.

Keywords: Climate performance; climate prediction; lars-wg; Pahang climate; SDSM

ABSTRAK

Ketidaktentuan cuaca kini membawa kepada bencana alam yang dahsyat terutama kepada kawasan yang tidak dijangka dan dalam masa yang tidak menentu. Oleh itu, unjuran perubahan iklim menjadi maklumat penting terutama dalam reka bentuk, perancangan dan pengurusan sumber air dan sistem hidro. Pelbagai model iklim dengan metod dan tujuan yang berbeza telah dibangunkan untuk menjana senario iklim setempat dengan mengambil kira kesan gas rumah hijau yang dibekalkan oleh Model Sikulasi Umum (GCMs). Namun, ketepatan dan keseimbangan setiap model iklim adalah bergantung kepada pemilihan ciri atmosfera dan variasi yang digunakan untuk membentuk persamaan statistik bagi hubungan cuaca setempat-global. Dalam kajian ini, 2 model iklim statistik telah digunakan; Model Lars-WG dan Model SDSM mewakili kaedah regresi dan kaedah cuaca penaipan. Tujuan utama adalah untuk menilai prestasi antara model yang bersesuaian dengan kebolehubahan iklim di Pahang pada tahun 2050. Keputusan telah menunjukkan bahawa Lars-WG sebagai model iklim yang boleh dipercayai tanpa memerlukan sumber data yang banyak dan menggunakan kaedah yang lebih mudah berbanding SDSM. Ia juga dapat menghasilkan keputusan simulasi yang lebih baik dengan %MAE yang lebih sedikit dan nilai R menghampiri 1.0. Walau bagaimanapun, SDSM mengungguli bagi simulasi suhu dengan mengambil kira parameter meteorologi yang paling berpengaruh dalam analisis. Keputusan unjuran iklim menunjukkan bahawa suhu dianggarkan akan meningkat sehingga mencecah 35°C. Walau bagaimanapun, model tersebut menghasilkan laporan unjuran hujan yang tidak tekal dengan hujan tahunan dianggarkan meningkat sebanyak 2.6% oleh SDSM dan berkurangan sebanyak 1.0% oleh Lars-WG daripada sejarah aliran dengan anggaran bahawa hujan lebat tertumpu pada bulan Nov.

Kata kunci: Iklim Pahang; jangkaan iklim; lars-wg; prestasi iklim; SDSM

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*Pengarang untuk surat-menyurat; email: nadrah@ump.edu.my