The Caribbean’s sandy beaches, clear turquoise water and vibrant coral reefs filled with an amazing variety of sea creatures have long been the pride of the islands.

The big three – sun, sea and sand – have made this tropical paradise the most tourism-reliant region in the world.

But now, all of that is under threat. The explosive growth of a type of seaweed called sargassum is wreaking havoc on economies, coastal environments and human health across the islands.

I study the intersection of critical infrastructure and disasters, particularly in the Caribbean. The sargassum invasion has worsened since it exploded in the region in 2011. Forecasts and the seaweed already washing up suggest that 2024 will be another alarming year.

The Sargasso Sea is often referred to as a golden, floating rainforest for its vast floating sargassum blooms and the wide variety of sea life that it supports.

It is the only sea in the world with no land borders. Instead, it is bounded by four Atlantic Ocean currents: the North Atlantic current, the Gulf Stream, the North Atlantic Equatorial Current and the Canary Current.

Without human interference, and under normal conditions, sargassum is a good thing. It has existed in the Caribbean for centuries, providing habitat and food for ocean wildlife, including threatened and endangered species such as the porbeagle shark and the anguillid eel.

Conditions over the past decade around the Caribbean Sea, North Atlantic and Gulf of Mexico, however, have been anything but normal.

Since 2011, vast mats of sargassum seaweed have been washing up on Caribbean islands. On shore, they pile up into a dead and stinky mass.

These sargassum events have been........

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