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by SeniorSenior 1760 days ago
On TED talks, Allan Savory promotes intensive rotational grazing as a proven means of reversing desertification. He observes that grass and herbivores and predators co-evolved. If you remove the predators, the herbivores thrive until the grass is gone. He shows a photo of adjacent parcels of land. One photo is of bare ground, dry stream bed, and leafless trees; The other photo is of running water, tall grass, brush and trees. The difference between parcels is attributed to managing grazing as if the predators were still there.

A third of Earth's land is desert. Alfalfa produces roughly ten tons per acre or 6400 tons per square mile. There are about 65 million square miles of desert. If 20 million square miles could be "greened" that would represent 128 billion tons of carbon per year removed from the atmosphere. Side effects would be healthier animals, higher quality food, and increased land area suitable for habitation.

In 2019 about 43 billion tons of CO2 were released into the atmosphere. Planting a third of the deserts to alfalfa would remove three times that annually.

Posit: We know how to cleanse the atmosphere.

Question: How do we make it happen?

Proposed: Revive the Homestead Act. Give people 160 acres of trash-land if they will make it grow. (A flaw in the original Homestead Act was the requirement that people live on their homestead. We should not require that, but I imagine people will want to settle on their homesteads once greened.)

Water is a necessary part of this plan.

Airwells are cold spots that condense water from air absent the conditions for rain or fog – if you’ve got dew spots on your windshield, you’ve got an airwell. Grass that condenses dew, is an air well. Basements that are moldy might be an airwell.

History and archaeology tell us that man-made airwells have been around for a long time. They come in many styles and have many names. Byzantine Rockpile, Crusader Siege Pond, Dew Pond, Ship Pond, Cloud Pond, Russell Dew Reservoir, Gravel Mulch, Herodotus’ Persian Palace Spring, WaterSeer…

I’m not interested in any version of an airwell that uses fuel. The ones I’ve named are all passive with the exception of the Siege Pond which benefits from a little muscle twice a day.

With $20k I’d build a Neolithic air well because I’m pretty confident it will work. With $200k I’d build them all to compare how well they work. Give me $2M and I’d build of each style in every state, because we need to know how each style performs in different environments.

Given water and free land as an economic incentive to grow grass, we can cleanse the atmosphere.

I am confident I can make a Neolithic Dew Pond the old way, with grass and clay and rocks. Would it work the same if built of foam-board and concrete? To be determined.

We know that low mass air wells work because we can see them work and we can buy the book “Dew Harvest.” Low mass devices do work but their production is not agriculturally and economically significant; Production is about five liters per day and seasonal.

According to the literature an eight hundred square-food Neolithic Dew Pond produces 660 gallons per day. That is a little less than three-quarters of an acre-foot per year.

Three-quarter acre-foot of water is agriculturally significant.

Economic significance depends on capital cost and productivity in diverse climates. Give me the $2M and I’ll find out if they can be made economically significant.

PS: States and companies which have bet on “scarce water” would be hurt by a thriving airwell industry.

PSS: If airwells become as common as they once were, manufacturers of home water-purification equipment will prosper.