Did Humans Create the Sahara Desert?

sciencedaily.com

16 points·martian··6 comments

Some think that the Amazon could flip to desert, with enough deforestation.

Amazon is on the equator, whereas Sahara is on tropic (north limit). Different kind of climate happens on those two latitudes.

Well, much of the Amazon is south of the equator. And reduced temperature difference between equator and poles will arguably weaken circulation.

If it was destroyed by humans, maybe it can be restored by humans.

If a change in planetary albedo can disrupt weather patterns, then gross control should likely afford for a reversal. If you could change the reflective surface of country-sized zones, would the opposite be possible?

What if the general reflective surface of uninhabited areas were darkened across the spectrum, but especially in the radiative thermal and infrared region? Would monsoons return?

10,000 years is pre-historic. I wonder how many seasons were required to transform the region, given that the desert continues to expand even today.

If monsoons were returned, figure 2 generations of monsoons (40 years) might show significant reversal?

"What if the general reflective surface of uninhabited areas were darkened across the spectrum, but especially in the radiative thermal and infrared region? Would monsoons return?"

When you "darken" something it means that the amount of energy in that portion of the spectrum is absorbed, naturally as heat. Hot bodies emit in infrared wavelength, i.e. will "leak" that heat. So, it's not enough to darken an area, you also have to make sure the energy gets used/consumed somehow, at least partially. Vegetation does that naturally.

So, if the albedo consumes infrared thermal energy with solar collectors, and converts to electricity, stored in batteries which then perform work, the concept holds water.

Reply on news.ycombinator.com