Why is the water in Alor so cold and clear?
Alor's water is cold and clear because it lies on one of the main outflow paths of the Indonesian Throughflow, the ocean current that carries warm Pacific water through the archipelago into the Indian Ocean. Oceanographers estimate the total flow at around 15 million cubic metres per second, and a large share passes through the Ombai Strait north of Timor and the Pantar Strait beside Alor.
Where that water meets steep slopes and narrow channels it mixes with deeper, colder layers. Upwelling cold water is rich in nutrients, which feeds plankton, which in turn supports the fish life and the dense hard coral that stands out on Alor's reefs. The same process explains why the Pantar Strait can feel like two different oceans on one dive.
The flow also makes the timing of each dive critical. Guides plan entries around tide tables and often change the order of sites on the day. This is one reason Alor suits divers with an Advanced Open Water certification and recent drift experience, and why a Drift Diver specialty is a useful warm-up.
