ABSTRACT. Debates have been going on for several years regarding the issue of global warming and subsequent sea level rise. Are humans one of the contributing factors to the warming of the Earth’s temperature? Or is it just a natural phenomenon and there is nothing to be worried about? Whatever it is, global warming, the increase of average global air temperature, is one of the most talked about and of high concern issues today, not just amongst the scientists, but also the general public. The rise of air temperature and subsequent increase in sea surface temperature (SST) will raise the sea level due to thermal expansion. These changes in water temperature could affect the health of many aquatic species, in addition to causing land loss and beach erosion. For the past 10 years (2000 until 2009), the average air temperature change in Kota Kinabalu, Sabah is approximately 0.10°C and according to these trends for the next eleven years (until 2020), the projection of air temperature change will be approximately0.21°C. When this happens, average sea surface temperature (SST) will also increase due to the relationship between air temperature and water temperature, though the change in SST may not be as large as the air temperature increase. The empirical relationship obtained in this study for air temperature and SST is SST = 0.241T + 22.6, with air temperature, T. As a rule of thumb, an increase of 1°C in SST can raise sea level by approximately 1 cm.. Using the SST data for the last eleven years, the change of SST is also calculated, as well as the projected SST changes for the next decade. Based on the last decade’s data, SST in Kota Kinabalu has increased 0.26 °C and it will increase another 0.24 °C by 2020. Sea level in Kota Kinabalu has also increased by 2.6 mm inthe last 11 years. Projections show that sea level in Kota Kinabalu will increase another 2.4 mm by 2020. Using the estimated value of sea level rise due to SST increase, land loss is also estimated for the coastal areas in Kota Kinabalu and the calculation is explained.
KEYWORDS. Air temperature, beach angle, beach loss, sea level rise, sea surface temperature