SOLAR SOLUTIONS

Marathon City Council workshop to focus on new co-op

from page 4 washes ashore isn’t as simple as scooping it all up and using it for fertilizer.

With such a high arsenic content, the macroalgae can’t safely supplement any plant intended for human consumption.

How did we get here?

Lapointe has studied sargassum since the 1980s, but he said that as he analyzed tissue from algae in the belt in more recent years, one nutrient in particular stood out.

“I was analyzing data from the 1980s that I collected. … In comparing those numbers with post-2010 data, that’s where we see nitrogen levels going up 35%, and the nitrogen:phospate ratio went up by 111%. That was my eureka moment,” he told the Weekly. “This sargassum looks like it’s being fed by the major rivers like the Amazon, the Orinoco, the Congo and the Mississippi.

Marathon residents can join the Marathon City Council workshop on Tuesday, March 28 to learn more about the logistics and cost savings of going solar.

CONTRIBUTED

Tired of rising electric bills? Join the Marathon City Council and Solar United Neighbors (SUN) for Florida Solar 101 at the Marathon City Hall on Tuesday, March 28 at 4:30 p.m. The solar experts at SUN will walk residents through solar technology, economics, incentives and how the co-op works. Participants can register in advance at SolarUnitedNeighbors.org/Keys/ Events; however, registration is not a requirement to attend.

The solar co-op will help area homeowners and small business owners learn about solar together and purchase solar panels at a group rate from a single installer. It’s a great time to go solar by joining the free Florida Keys 2023 Solar Co-op. The Keys co-op is sponsored by the city of Marathon, city of Key West, city of Layton, League of Women Voters of the Lower Keys and IFAS Monroe County.

More information is at solarunitedneighbors.org/keys.

— Contributed

“It just so happens that the nitrogen and phosphorus contents are highest in the winter and spring, just when the rivers are discharging the most. … By summertime, those river discharges are actually going down, and that’s when the growth slows down as tissues become depleted of nitrogen and phosphorus.”

Over the past 12 years, a formerly limiting nutrient to the growth and biomass of the belt ceased to be a handcuff, as human population growth fueled high reactive nitrogen levels with wastewater, fertilizers, deforestation and other contributors, Lapointe said. The belt is capable of doubling its size in anywhere from two to four weeks under ideal conditions, and with the algae continuing to exhaust the amount of available phosphorus, another critical nutrient, it turns to a chemical analog: arsenate, a salt of arsenic acid.

Adding further fuel to the fire are rising sea temperatures.

“The winter temperatures are anywhere between two to six degrees higher than what we’d typically see at this time of year,” said Bruckner. “We’ve now shifted to an El Niño event … (and) because it’s already warmer than it should be this year, that could help fuel the growth.”

Where are we now?

Researchers began actively tracking the size of the belt with multiple methods, including satellite imagery, during the first bloom in 2011. Since then, the 2018 bloom has been the recordsetting standard, with 2022 as another severe event.

Thus far in 2023, the blob had an early start to its annual growth. But the final impact is yet to be seen. A sargassum outlook summary published by the University of South Florida’s Optical Oceanography Lab noted that “although the overall sargassum quantity in the central Atlantic Ocean decreased from January to February … this abundance (6.1 million tons) is still the second-highest amount recorded for the month of February. … (And) within the Caribbean Sea, sargassum quantity nearly doubled.

“The decrease in sargassum quantity from January to February is uncommon, and presents a glimmer of hope that the overall 2023 bloom may not be as large as previously feared,

While it serves many important ecological purposes, excessive quantities of the brown macroalgae known as sargassum can pose ecological and human health risks. KEYS WEEKLY FILE PHOTO although 2023 will still be a major sargassum year,” the outlook concludes.

Though beaches throughout South Florida are already starting to see sargassum arriving as March gives way to April, Bruckner said it’s too early to define the severity of this year’s event.

“One of the fears, I think, is that it’s a little earlier than normal,” he said. “And, you know, there is the potential for it to get much, much worse than it is, but it’s sort of hard to predict that.”

Where do we go from here?

With sargassum research a growing priority over the last decade, further work using satellites to track fine-scale current data should prove crucial in accurately predicting movements of algae within the belt.

Physical barriers and collection apparatuses are important pieces of the puzzle to combat large accumulations of the algae on shore, but with the belt affecting so many diverse areas, there’s no single defense method that’s perfect for all.

One possible solution may rest with SOS Carbon, a spinoff organization from the mechanical engineering department at the Massachusetts Institute of Technology (MIT) that engineers solutions for sargassum collection and disposal. A net-based Littoral Collection Module developed by the organization can continuously collect the algae, while a second Sargassum Ocean Sequestration of Carbon process periodically sinks large collections of sargassum to depths that collapse its air bladders, preventing it from resurfacing and continuing to absorb buoyant nutrient plumes from rivers. As Lapointe noted, such a process would also chip away at environmental carbon dioxide levels by sending CO2 absorbed by the macroalgae to the ocean floor for years.

For a health briefing on sargassum produced by the Florida Department of Health, visit https://www.floridahealth.gov/environmentalhealth/beach-water-quality/_documents/sargassum-factsheet-appr-final.pdf.

To visit USF’s live sargassum watch system, including an interactive map, visit https://optics. marine.usf.edu/projects/saws.html.