Analisis taburan hujan dan impaknya kepada sumber air di Pulau Pinang (Rainfall distribution and its impact on Penang’s water resource)

Abstract

Kajian dan analisis taburan hujan tahunan dan bulanan ini adalah bertujuan untuk melihat tren atau pola taburan hujan berdasarkan perubahan iklim dan musim di daerah Timur Laut, Pulau Pinang. Selain itu, hasil kajian boleh digunakan dalam merangka pengurusan kepada penggunaan air di Pulau Pinang bagi mengenalpasti sumber air dan kitarannya. Rekod taburan hujan kawasan kajian daripada lima buah stesen Jabatan Pengairan dan Saliran selama sepuluh tahun (2001 hingga 2010) telah dikumpulkan dan dianalisis mengikut jumlah hujan tahunan dan bulanan. Perbandingan telah dibuat berdasarkan skala ruangan dan skala masa. Analisis perubahan pola tumpuan jumlah hujan telah menunjukkan bahawa majoriti tahun mempunyai tumpuan jumlah hujan di bahagian utara dan barat laut kawasan kajian (tahun 2001 hingga 2002, 2006 hingga 2009). Manakala pada tahun 2003 hingga 2005, dan 2010 tumpuan hujan beralih ke kawasan timur laut dan timur. Seterusnya, hasil daripada analisis taburan hujan tahunan mengikut skala
masa pula mendapati bahawa semua stesen telah menunjukkan perubahan menaik dari segi jumlah hujan
daripada tahun 2001 hingga 2010 kecuali stesen Kolam Bersih.

Katakunci: kitaran air, perubahan iklim, pengurusan air, pola taburan hujan, punca air, tumpuan hujan

This paper presents the findings and analysis of a study on the distribution of annual and monthly rainfall based on climate and seasonal change in the Northeast district of Penang, Peninsular Malaysia. The findings, it is proposed, may be used in the management of Penang’s water resources, in particular, with respect to the identification of water sources and its cycle. Records of the rainfall distribution were gathered from five stations of the department of Drainage and Irrigation for the ten year period of 2001 to 2010. The data were then analysed according to annual and monthly rainfalls while comparisons were made based on both spatial and time scales. The analyses of the rainfall concentration patterns demonstrated that for the majority of the years observed (2001 to 2002, 2006 to 2009) rainfalls had concentrated in the north and northwest parts of the district. By comparison, rainfalls had concentrated on the east and northeastern parts of the district for the lesser period of 2003 to 2005, and 2010. All areas analysed showed that except for the Kolam Bersih station all stations had experienced marked increases in rainfall quantities for the period 2001 to 2010.

Keywords: climate change, rainfall concentration, rainfall distribution patterns, water cycle, water management, water sources