A global shift is underway, with scientists warning of a profound change to our oceans. Seaweed blooms, once rare, have been expanding at an alarming rate - 13.4% per year over the past two decades - driven primarily by global heating and pollution from farming runoff.
The phenomenon is being dubbed a "regime shift" in the ocean's ecosystem, where the dominant types of seaweed are changing, and with it, the fundamental chemistry and ecology of the water beneath. This shift could have far-reaching consequences, including accelerating climate breakdown and altering the atmosphere's ability to regulate heat.
Experts point to 2008 as a key tipping point, after which the growth of macroalgae - or "seaweed" in everyday terms - began to surge globally. Since then, regions like the Atlantic and Pacific have seen massive blooms of sargassum, with some stretches visible from space.
The researchers behind the study used satellite images and artificial intelligence to detect the signs of seaweed blooms across 1.2 million images taken over a decade. They found that macroalgae had increased in area by 13.4% annually, while microalgae growth was more modest, at just 1% per year.
The team suggests that this shift is linked to accelerated ocean warming and eutrophication - the enrichment of water with nutrients from pollution. While some types of seaweed have thrived in certain regions, phytoplankton have not shown similar responses, implying their growth may be more sensitive to changes in temperature and pollution.
If macroalgae continue to dominate our oceans, it could lead to significant impacts on climate regulation, light availability, carbon sequestration, and ocean stability. The study's findings were published in Nature Communications, providing the first comprehensive picture of algae floating in our world's oceans.
The phenomenon is being dubbed a "regime shift" in the ocean's ecosystem, where the dominant types of seaweed are changing, and with it, the fundamental chemistry and ecology of the water beneath. This shift could have far-reaching consequences, including accelerating climate breakdown and altering the atmosphere's ability to regulate heat.
Experts point to 2008 as a key tipping point, after which the growth of macroalgae - or "seaweed" in everyday terms - began to surge globally. Since then, regions like the Atlantic and Pacific have seen massive blooms of sargassum, with some stretches visible from space.
The researchers behind the study used satellite images and artificial intelligence to detect the signs of seaweed blooms across 1.2 million images taken over a decade. They found that macroalgae had increased in area by 13.4% annually, while microalgae growth was more modest, at just 1% per year.
The team suggests that this shift is linked to accelerated ocean warming and eutrophication - the enrichment of water with nutrients from pollution. While some types of seaweed have thrived in certain regions, phytoplankton have not shown similar responses, implying their growth may be more sensitive to changes in temperature and pollution.
If macroalgae continue to dominate our oceans, it could lead to significant impacts on climate regulation, light availability, carbon sequestration, and ocean stability. The study's findings were published in Nature Communications, providing the first comprehensive picture of algae floating in our world's oceans.