What is the Indonesian Throughflow

What is the Indonesian Throughflow

Located between the Pacific and Indian Oceans, the Indonesian Seas are a place of immense water exchange

The water exchange is the Indonesian Through-flow and flows from the Pacific to the lower Indian Ocean. This flow delivers eggs and larvae to the reefs of Indonesia and travels over the complex underwater topography creating great upwellings of nutrient-rich cold water. Both the marine diversity and importance of research tie back to the Indonesian Through-flow Current, which passes through Raja Ampat. This critical current provides a route for warm water to flow from the Pacific to the Indian Ocean and is an essential path for the global heat conveyor belt (which warms up oceans internationally and maintains the overall climate worldwide).

A veritable life source, and after a holiday in these waters, you will go home with a renewed sense of life.

We are sure you have heard numerous times that Raja Ampat boasts the best waters and most abundant marine life in the South-East Asian region. Science considers it one of the world's premier sites for marine biology. It has been recorded as holding 75% of all known species of ornamental and coral fish worldwide. It continues to be a vital spot for researchers seeking to develop knowledge of marine life.

But the question stands, why is Raja Ampat’s water so full of life?

What is the Indonesian Throughflow
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We have already spoken about the Indonesian Through-flow, but one needs a clear explanation to understand the strength of this current utterly. Norwegian scientist Harald Sverdrup even made up his term to explain the vast amount of liquid flowing here. He said to imagine “a river that is 100 meters wide, 10 meters deep and flows at speeds of 4 knots, then imagine 500 of those rivers all combined.” This is one Sverdrup… The Indonesian Through-flow is 22 Sverdrup's!!

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According to Conservation International – the undoubtable reason for Raja's resilient reefs is complex and numerous but believed that one of the most important factors is that its reefs are usually exposed to a wide variation in temperatures, basically “pre-adapting” them to climate change.

Reefs across Raja Ampat experience temperatures fluctuating between 19 and 36 degrees Celsius (66 and 96 degrees Fahrenheit), with many individual reefs exposed to a whopping 6–12 C variation within a single 24-hour period! According to most marine biology textbooks, such variation should quickly kill these corals, yet they are thriving.

As scuba divers and marine biologists began to travel to the more remote eastern parts of Indonesia, they discovered the absolute wonder of Raja Ampat's biodiversity. It was soon realised that Raja Ampat was far more important to marine conservation than anyone had ever thought, and agencies like Conservation International, the World Wildlife Fund, and the Nature Conservancy started to move in.

About Meridian Adventure Dive  

Situated in Raja Ampat, IndonesiaMeridian Adventure Dive is a PADI 5 Star Resort and winner of the PADI Green Star award. Scuba divers enjoy our professional services that have become synonymous with both the PADI and Meridian Adventure names.


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