Sains Malaysiana 43(9)(2014): 1389–1396

Variations of Southern South China Sea Characteristics near Pahang

(Perubahan Ciri Laut China Selatan Bahagian Selatan Berdekatan Pahang)

NUR HIDAYAH ROSELI¹* & MOHD FADZIL MOHD AKHIR²

¹School of Marine Science and Environment, Universiti Malaysia Terengganu

21030 Kuala Terengganu, Terengganu, Malaysia

²Institute of Oceanography and Environment, Universiti Malaysia Terengganu

21030 Kuala Terengganu, Terengganu, Malaysia

Received: 2 April 2013/Accepted: 31 January 2014

ABSTRACT

Oceanographic cruises in Pahang water in October 2003 and April 2004, monsoon transition months, produce data on water characteristics. The temperature in both months showed higher values in nearshore compared to the offshore stations. The nearshore salinity in both months is lower than offshore stations. Comparatively, there were smaller differences in temperature and salinity in October than in April, with very little variation between nearshore and offshore stations. T-S diagram showed significant differences between October and April water characteristics. According to the water characteristic observations, the temperature and salinity in October was lower than in April, while dissolved oxygen was higher than in April. The lower temperature and salinity taken during the sampling time in October suggested that during this time, the study area already received the influences of strong winds due to upcoming monsoon. The warmer and saltier water obtained in April showed that during this time, the study area was influenced by southwest monsoon. Winds related to rainfall were observed to have impact to the dynamics of water characteristics during both months.

Keywords: Current circulation; monsoon transition month; salinity; South China Sea; temperature

ABSTRAK

Pelayaran oseanografi di kawasan perairan Pahang pada bulan Oktober 2003 dan April 2004, bulan peralihan monsun, menghasilkan data mengenai ciri air. Suhu air pada kedua-dua bulan menunjukkan nilai yang lebih tinggi di kawasan pesisir pantai berbanding dengan stesen luar pesisir. Kemasinan di kawasan pesisir pantai pula adalah lebih rendah daripada stesen luar pesisir bagi kedua-dua bulan. Secara perbandingan, terdapat perbezaan kecil dalam suhu dan kemasinan pada bulan Oktober berbanding bulan April, dengan perubahan yang sangat sedikit di antara stesen berhampiran pantai dan luar pesisir. Gambarajah TS menunjukkan perbezaan yang signifikan antara ciri air pada bulan Oktober dan April. Menurut pemerhatian ciri air, suhu dan kemasinan pada bulan Oktober adalah lebih rendah berbanding pada bulan April, manakala oksigen terlarut adalah lebih tinggi berbanding pada bulan April. Suhu air laut dan kemasinan yang lebih rendah yang diambil pada bulan Oktober memperlihatkan bahawa pada masa ini, kawasan kajian telah menerima pengaruh angin kuat berikutan monsun yang bakal tiba. Suhu laut yang semakin panas dan masin yang diperoleh pada bulan April menunjukkan bahawa pada masa ini, kawasan kajian telah dipengaruhi oleh monsun barat daya. Angin yang turut berkaitan dengan hujan diperhatikan memberi kesan kepada ciri dinamik air pada kedua-dua bulan

Kata kunci: Bulan peralihan monsun; kemasinan; Laut Cina Selatan; peredaran arus; suhu

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*Corresponding author; email: nurhidayahroseli@gmail.com