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0 pointsbcrosby952y ago0 comments

The Sahara desert is 3.5 million square miles. That will never be re-forested.

0 comments

Never is a pretty long time. One of my favorite authors: Doris Lessing, wrote a book called: "Mara and Dan" which has a very interesting take on climate change. I would recommend all of her books to anyone who wants to stretch their perception of our world.

VintageCool2y ago

Okay, sure, if you look at geologic timescales then eventually Africa will move and the region of northern Africa will cease to be desert.

Within a human timescale, I think "never" is an acceptable term.

Atmospheric circulation means that the latitude of the Sahara is blasted with cool dry air from the upper atmosphere. Humans planting trees might slow the spread of the desert, but will not vanquish it.

To disrupt the effects of atmospheric circulation (ie Hadley cells) creating deserts at those latitudes, you'd need mountain ranges and oceans.

https://en.m.wikipedia.org/wiki/Hadley_cell

dev1ycan2y ago

"For several hundred thousand years, the Sahara has alternated between desert and savanna grassland in a 20,000-year cycle caused by the precession of Earth's axis (about 26,000 years) as it rotates around the Sun, which changes the location of the North African monsoon."

https://en.wikipedia.org/wiki/Sahara#:~:text=For%20several%2....

evandale2y ago

Why are we working in human timescales? It's like saying the sun will never burn out because humans won't be around to see it happen.

To me, that's a pretty bold and naive claim.

2 more replies

bigbillheck2y ago

Not with that attitude.

hooverd2y ago

Found the Shai-Hulud.

j / k navigate · click thread line to collapse