In 1965,without suggesting how reflective grains would be made, Revelle and others published the idea of floating small reflective grains on oceans to reduce global warming.
In 2021, Haley and Nicklas proposed making such grains as small tiles of glass foam and floating them in the North Atlantic Gyre to reduce hurricane damage while achieving long life before the tiles wash onto beaches. The tiles can also increase alkalinity of the surface water to increase absorption of CO2 and can release nutrients to stimulate organic growth to fix carbon and sink to the bottom of the ocean.
Methods of producing these tiles are varied but use readily accessible materials like sand and can be achieved using power attained by low-carbon methods, like photovoltaic panels. Following Mie theory, transparent material such as glass can be made highly solar reflective by forming alternating pockets of air and glass where the air pockets and glass pockets each have average diameters of roughly one micron. This is why snow and clouds are white.
The objectives are to:
1. Reduce absorbance of solar energy and reduce water temperatures to reduce tropical cyclone damage and reduce coral damage;
2. Increase absorbance of CO2 from the atmosphere by maintaining high pH at the water surface over months and by reducing solar heat gain of the water;
3. Increase absorbance of CO2 from the atmosphere by supplying at the surface nutrients to promote the growth of organisms that fix carbon;
4. Reduce acidity to reduce suppression of coral growth when deployed up-current from coral reefs; and
5. Reduce the Earth’s energy imbalance to reduce global warming by reflecting solar energy to space.