MIAMI (CBSMiami/CNN) – South Floridians know the awful stench of seaweed on their local beaches all too well and a new study finds the annoying seagrass is sticking around – and may be even worse this year compared to last year.

Scientists with the University of South Florida College of Marine Science say the largest seaweed bloom in the world happened in the Atlantic last year and this year it could get even bigger.

Researchers used NASA satellite observations and other data to study the great Atlantic sargassum belt which is made up of brown macroalgae. They estimated that it weighed more than 20 million tons.

Last year, it stretched from the Gulf of Mexico to the west coast of Africa.

Scientists say the giant blooms are fueled by a mix of weather patterns and nutrients being dumped into oceans.

In small amounts, sargassum is beneficial, It provides a habitat for marine creatures and produces oxygen through photosynthesis. But too much makes it hard for species to move and breathe. It can also smother corals and seagrasses – and on the beach, when it dries, it releases hydrogen sulfide gas that smells like rotten eggs.

Sargassum has been an issue since 2011. Apart from 2013, each year the seaweed has returned in larger quantities.

Researchers say this year looks to be worse than last year and that sargassum could affect summer vacations across the region.

(©2019 CBS Broadcasting Inc. All Rights Reserved. Cable News Network, Inc., a Time Warner Company, contributed to this report.)