AUSTIN (KXAN) – A giant floating blob of Sargassum seaweed, floating in the Atlantic Ocean, can be detected and tracked all the way from space. It is already 5,000 miles long and an estimated 13 million tons.
This bloom of seaweed is expected to grow in size and, depending on the wind and ocean currents, impact more and more beaches. Seaweed that washes up on shore can cause devastation to the ecosystem as well as deter tourism.
Meteorologist Sean Kelly spoke with Dr. Edward Buskey, the Director of Marine Science at the University of Texas, to learn more about the cause of this increasingly large patch of seaweed. Read the interview below to learn more.
Sean Kelly, KXAN News: We hear a lot of the headlines of seaweed out in the Gulf taking over some of the beaches in Florida, can you can you tell me what you know about it? Why is it so large in size right now?
Dr. Edward Buskey, Director of Marine Science: Well, so Sargassum is an unusual seaweed. It has sort of a unique characteristic and that it can just float in the ocean. And so you can actually track this big blob of seaweed heading towards Texas from satellites. And so that’s why they have a pretty good idea about the size potential for the bloom this year. And so like any plant, right, what do plants need in order to grow, they need sunlight, they need water, and they need nutrients, you know, primarily things like nitrogen phosphorus that you put in your fertilizer that he used in the garden. So obviously, a plant like that that goes at the surface of the ocean has plenty of sunlight, because it’s right at the top of the of the water column. It has plenty of water, it’s living in water.
And so the main source that causes these blooms, we think it’s an increase in nutrients in coastal waters that are then ending up in the southern central Atlantic. Basically, the area where these things grow is just above the equator. So this thing starts in near Africa, just north of the equator and heads in our direction. So prevailing winds are from east to west, in that area, as well as the currents.
Kelly: Does climate change play a role? You think the warming in the Gulf, the sea surface temperatures, is that playing a major role?
Buskey: Well, that would that would increase the frequency of hurricanes as we’ve seen in the last decade. And so again, the path that a hurricane takes, it tends to mix that water up from very deep in the ocean, and that water has excess nutrients in it. So when when plants and animals die, they sink into the ocean, most of the wherever there’s enough sunlight, those nutrients get used up below that depth where there isn’t enough sunlight, those nutrients tend to accumulate. And so when you mix that deep water back up to the surface, that can fuel not only phytoplankton growth, but also Sargassum.