Move aside, Aquaman, a new hero of the oceans has arrived! Whilst its abs may not match up to those of Jason Momoa, when combatting the two monsters of marine climate change – warming and acidification - this hero may be second to none.
When picturing reforestation projects, most people imagine vast forests on land, like an Amazon rainforest. However, below sea level lives a crucial carbon sink that could provide food and income for nearby communities, increase biodiversity, decrease ocean acidification, produce renewable energy and store carbon. This nature based solution isn’t futuristically high-tech – it’s simply, seaweed.
When picturing reforestation projects, most people imagine vast forests on land, like an Amazon rainforest. However, below sea level lives a crucial carbon sink that could provide food and income for nearby communities, increase biodiversity, decrease ocean acidification, produce renewable energy and store carbon. This nature based solution isn’t futuristically high-tech – it’s simply, seaweed.
Kelp forests are one of the most productive and biodiverse environments on the planet. They create an oasis of life wherever they grow, providing food and shelter for fish, invertebrates and marine mammals. Plus, they may be a vital tool for mitigating climate change as they can store vast amounts of carbon. Studies suggest that kelp forests may be able to store up to 250 million tonnes of carbon per year, globally (around the equivalent of the carbon emissions of Egypt).
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However, these incredible ecosystems are disappearing at an alarming rate due to rising ocean temperatures, acidification and increasingly extreme weather. Australia alone has already lost 95% of its kelp forests.
The Climate Foundation has developed a method of growing kelp forests below sea level on irrigation platforms, known as Marine Permaculture Arrays (MPAs). Nutrient-rich, cold water is pumped from deep down in the ocean to the platform, recreating pre-global warming temperatures and providing all the nutrition the plants need to grow up to 61cm a day!
As the kelp forests grow they draw the greenhouse gas, CO2, from our oceans and our ever thickening atmosphere, helping to cool the planet, whilst simultaneously improving ocean conditions for sea life by cooling the water and reducing acidification. This leads to a plethora of fish species, shellfish with stronger shells, and brightly coloured, vibrant coral reefs. |
Once harvested, the best of the kelp can be used for numerous products including food, biofuel, animal feed and fertilizer. However, the most important part is the climate-saving storage of the carbon, so the majority of the seaweed is sunk to the bottom of the ocean where the carbon can be stored for millenia. According to the Climate Foundation, each dry ton of kelp sequesters one ton of CO2.
If all of that weren’t enough, there are even further benefits:
- Farming seaweed and the increased fish catch from the restored ecosystem, generates income for nearby communities,
- Using biofuel produced from seaweed for electricity reduces our dependence on fossil fuels,
- Feeding seaweed to cattle has been proven to reduce their methane emissions by up to 90%,
- Algae from the Marine Permaculture Arrays can be used as a plant-based source of omega-3, reducing the pressure on fish farms.

The MPAs are completely sustainable, using wave energy to pump the cold water to the platform and produce enough kelp to maintain a harvest every 90 days, while being at a depth of 25metres protects the platforms from damage by extreme weather or shipping.
As with all reforestation projects, this does not let us off the hook in terms of preventing climate change through other measures like flying less, eating less meat and burning less fossil fuel, but it may be a vital part of the solution to keeping global temperature rise below 2°C.
The Climate Foundation’s trials have proven that their marine reforestation technology works. That’s why JUST ONE Tree has joined forces with them on this exciting venture to sequester carbon from our oceans.
The Climate Foundation’s trials have proven that their marine reforestation technology works. That’s why JUST ONE Tree has joined forces with them on this exciting venture to sequester carbon from our oceans.