Fenomena Pulau Haba Bandar dan isu alam sekitar di Bandaraya Kuala Lumpur (The Urban Heat Island phenomenon and the environmental issues of Kuala Lumpur City)

Abstract

Pulau Haba Bandar (PHB) bukanlah sesuatu fenomena baru yang wujud dan terbentuk di kebanyakan bandar raya besar di dunia hari ini. Keadaan ini dialami juga oleh kebanyakan bandar-bandar besar di Malaysia sejak beberapa dekad di penghujung kurun yang lalu. PHB boleh didefinisikan sebagai pengaruh morfologi bandar terhadap parameter iklim dan cuaca semula jadi yang wujud di persekitaran bandar. Umumnya, peningkatan suhu dapat diperhatikan berlaku di kawasan-kawasan tepubina di dalam bandar berbanding dengan kawasan-kawasan pinggir dan luar bandar. Kebanyakan kajian membahaskan isu alam sekitar pulau haba bandar ini dengan mengaitkan faktor perkembangan bandar dan perindustrian yang begitu pesat sehingga mampu merubah pola dan trend suhu semula jadi di persekitaran bandar. Justeru, berasaskan penyataan ini kajian ini cuba menganalisis aspek pola pulau haba bandar yang berlaku di Kuala Lumpur sejak kebelakangan ini. Dengan menggunakan teknik penderiaan jauh, imej satelit landsat TM dan ETM+ serta GIS digunakan bagi mengesan sebarang perubahan pola suhu yang berlaku di Kuala Lumpur mengikut pola gunatanah yang berbeza. Hasil kajian menunjukkan banyak kawasan yang merekodkan suhu sederhana tinggi manakala pola pulau haba bandar direkodkan di kawasan-kawasan seperti Jinjang-Kepong, Segambut-Sentul dan sedikit di sebelah selatan kawasan kajian. Fenomena pulau haba bandar yang dianggap sebagai isu alam sekitar bandar yang unit ini banyak berkait rapat dengan aspek pemuliharaan dan pemeliharaan alam sekitar bandar. Dapat dikatakan, di samping faktor fizikal, factor manusia juga amat penting dalam menentukan sejauhmanakah sifat kadar intensiti pulau haba bandar.

Katakunci: imej satelit, kadar Bowen, kawasan tepubina, keselesaan terma, Pulau Haba Bandar

Urban heat island (UHI) is not a new phenomenon for many of the mega cities in the world today. It is also experienced by most of the big cities in Malaysia since the last few decades. UHI can be defined as the influence of urban morphology upon natural weather and climate parameters within an urban environment. Generally, increased temperatures may be observed at urban built-up areas as compared to urban fringes and rural areas. Most researches of UHI discuss the environmental issues of urban heat island in relation to rapid urban development and industrial factors which tend to alter natural patterns and trends of temperatures within the urban environment. This study analyses some of these aspects of the UHI patterns in Kuala Lumpur in recent years by using remote sensing, TM landsat satellite imaging and ETM+ as well as GIS techniques to detect any temperature pattern changes in Kuala Lumpur, and in accordance with different landuse sectors. The results demonstrate that there were many areas that had recorded medium high temperatures such as Jinjang-Kepong, Segambut-Sentul and a few other locations at the south of the study area since UHI patterns were detected there. As an urban environmental issue the UHI phenomenon was closely related to aspects of conservation and preservation of the urban environment, which in turn denoted the fact that beside physical factors, human factors were also important in determining the nature of the UHI intensity in the Kuala Lumpur city.

Keywords: Bowen ratio, built-up area, satellite image, thermal comfort, urban environmental issue, Urban Heat Island