Sea level impact due to El Nino and La Nina phenomena from multi-mission satellite altimetry data over Malaysian seas

Abstract

The El Nino and La Nina phenomena indirectly provide dramatic changes to the sea level that can be caused by floods and drought, and affect various marine activities. For the past centuries, the main approach to measure sea level changes is by using coastal tide gauges. However, there is inconsistency in observing sea level variations using tide gauge data for the Malaysian country. The inconsistency is due to irregular geographical distributions of tide gauge stations established at coastal areas and there are no long-term tide records for the deep sea. An alternative method in order to solve this issue is by measuring the absolute sea level from space, i.e., satellite altimeter technique. Satellite altimeter implements excellent potential as an integral mechanism to the conventional coastal tide gauge instruments for monitoring sea level variation of Malaysian seas, especially for the deep sea. The aim of this research is to study the sea level pattern due to the effects of El Nino and La Nina phenomena using a combination of multi-mission satellite altimeters in the Malaysian seas. Radar Altimeter Database System (RADS) is used for retrieval and reduction of sea level data from satellite altimeter. Then, sea level data from tide gauge was used to verify satellite altimeter derive the sea level data. The result of this research shows that satellite altimetry is reliable in other to monitor changes in sea level. It also shows that El Nino and La Nina phenomena can also contribute as one of the factors to sea level changes around Malaysian seas. Hence, this research will specifically help in the determination of sea level in Malaysia and to the professionals who have authority in governmental, environmental planning, agriculture, marine engineering, and economics.