About 10% of the world's surface is desert, which is cheap, uninhabited, unproductive land that is drenched in some of the most powerful solar radiation on the planet. This approach seeks to leverage these attributes by flooding the desert with water to create millions of 1 km2 oases (shallow reservoirs with water) that can absorb and retain carbon with the potential benefit of creating newly habitable areas.
This system of oases would be used to grow phytoplankton. With additional desalinated water, it could irrigate the surrounding area to propagate vegetation as well as provide fresh water to nearby communities. These oases would operate similarly to the ocean phytoplankton cultivation concept but executed in a relatively controlled and, thereby, safer environment than in the ocean. Unlike BECCS, the oases would absorb CO2 via phytoplankton growth - phytoplankton produce biomass faster than agriculture, reducing the necessary surface area by almost 4x - which would be periodically harvested to extend the length of sequestration and set up downstream use as fertilizer or other higher value products. This would be the largest infrastructure project undertaken, making its scale the main challenge.