GreenWave is a North American nonprofit focused on the development of regenerative farming techniques for aquaculture, called "3D ocean farming", to create blue carbon.^[1][2][3] Their focus is on developing polyculture practices for farming shellfish and seaweeds and kelps.^[2][4] These practices include using many layers of the water column, emulating high activity water ecosystems like reefs, to increase productivity and biomass.^[5]

The organization focuses on developing globally accessible techniques for this kind of farming.^[6] As of 2019, they had a waitlist of over 4,000 farmers in 20 countries needing support in starting such farms.^[3] Starting such a farm usually costs between US$20,000–50,000.^[3] The nonprofit was created by Bren Smith to spread methods first developed on his Thimble Island Ocean Farm in Long Island Sound.^[7][8] Emily Stengal is the co-founder and deputy director of the non-profit.^[9]

In 2015, the organization's 3D ocean farming method won the Buckminster Fuller Institute's Fuller Challenge.^[8] The organization also won a 2017 The Index Project prize.^[10]