(CNN)A record-breaking mass of smelly seaweed stretching from West Africa to the Gulf of Mexico has been identified using satellite imagery.
Record-breaking seaweed bloom stretches from West Africa to Mexico
The seaweed bloom, called the great Atlantic Sargassum belt, is the largest ever of its kind, according to a new study.
Researchers at the University of Southern Florida used satellite imagery to determine that the giant floating mass of seaweed is a whopping 8,850 kilometers (5,000 miles) long. It weighs an estimated 20 million metric tons, or the equivalent of 1.6 million double-decker buses.
Scientists first noticed that seaweed was spreading rapidly across the Atlantic and growing in mass in 2011.
"There's a huge amount of Sargassum in a place where it's never been seen before," said Mengqiu Wang, co-author of the study, which was published in the journal Science.
Wang said the seaweed was of "great ecological value" to marine life such as fish, crabs, shrimps and turtles that use it as a habitat or food source.
But excesses of Sargassum like the recent explosion cause some problems for marine life, as dead Sargassum sinks to the ocean floor and can "smother corals and seagrasses", according to the university's press release.
Sargassum also releases a sulfur gas that smells like rotten eggs as it decays, which has caused problems as it washes up on tourist-filled coasts in Mexico and the Caribbean.
The rotting seaweed can attract insects and the gas given off affects asthma su