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Floating membranes to reflect sunlight to prevent ocean absorption of solar energy and thereby resist greenhouse warming.



Take a plastic bag from the grocery store. Pour in a glass of water. Squeeze out most of the air and seal the bag air/water tight. Toss it into the ocean.

Since fresh water is less dense than salt water, the bag will float. Since water wants to find its level, the water in the bag will spread itself out on the surface of the ocean, which will result in the bag being spread out over the surface of the ocean. Since the bag is white, it will reflect sunlight and prevent the water from absorbing solar energy.

The idea is scaleable. Bags the size of houses or city blocks or even bigger might be cheaper due to less seams.

Freshwater requirements are reasonable, because we only need a thin layer of water. The wastewater generated by a single household in a modern economy could cover 2-3 hectares with a layer 1 cm deep (about 1 acre at 3/8 of an inch deep) every day.

Unwanted negative environmental impact could be reduced by using a biodegradable plastic material.

Category of the action


What actions do you propose?

Who will take these actions?

Where will these actions be taken?

In oceans everywhere across the globe.

What are other key benefits?

Could be cheaper for coastal cities to "dispose" of their wastewater this way instead of building expensive waste water treatment facilities.

Local/targeted effects:

  • In the arctic, could slow the loss of sea ice.
  • In tropical seas, could reduce the energy of hurricanes/typhoons.

Really, really big bags might exhibit interesting behavior. Artificial atolls? Atolls are incredibly productive ecologically.

What are the proposal’s costs?

Time line

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