41–50 of 102 posts
I've heard about some efforts to regreen the desert by careful planting and geoforming. Anyone know anything about this? It would be cool if it could work, even partially.
Check out the work being done by https://justdiggit.org/
https://justdiggit.org/what-we-do/landscape-restoration/wate...
(That site breaks the url bar though; I had to get that via a search engine. Wtf.)
I think it was in Michael Palin's show Sahara, he's talking to some locals living in a village in the middle of the desert, and while I'm wondering why anyone would ever settle out there, the person being interviewed relayed that many more people used to live there before it became a desert. It wasn't that they moved out there, they were all that was left. Kind of post-apocalyptic. Edit: found the mention, he's talki…
The Earth's precession cycles driving Sahara rainfall have a period of about 23,000 years. Whatever caused deforestation there over the past 500 years likely was distinct from the Green Sahara cycles.
Earlier quoted context omitted.
What’s the proposed mechanism for that? It doesn’t seem plausible to me on the surface.
I don’t know about Arizona, but apparently, parts of the great plains were dense forest that Europeans clear cut, and they simply never recovered. Also, California used to be green in the summer, but then people introduced non-native grass that grows rapidly in spring, choking out the native plants, but dies by July. It is the reason the hills are so yellow and dusty and dry. There is some stuff along route 66 that s…
I've heard about some efforts to regreen the desert by careful planting and geoforming. Anyone know anything about this? It would be cool if it could work, even partially.
https://www.earthdate.org/episodes/darwins-terraforming-expe...
I think it was in Michael Palin's show Sahara, he's talking to some locals living in a village in the middle of the desert, and while I'm wondering why anyone would ever settle out there, the person being interviewed relayed that many more people used to live there before it became a desert. It wasn't that they moved out there, they were all that was left. Kind of post-apocalyptic. Edit: found the mention, he's talki…
Apparently Libya has a huge ancient aquifer (or several aquifers really) that they built pipelines to access, and now that's their main source of fresh water.
The aquifers, being left over from a previous era when Libya got a lot of rain, are not being refilled by anything.
Earlier quoted context omitted.
It's not really a "theory" as anyone normal uses that term. We know beyond any reasonable doubt that there's significant genetic, cultural, and political ancestry tying modern Puebloan groups to the the people who inhabited Mesa Verde (and other earlier pueblos). "Most" went east to the Rio Grande area, but plenty went west too. Some Hopi ancestry also comes from other groups to the north, west and south (into modern…
Do you have a citation on mesquite spreading from Texas with cattle? I ask because the aforementioned information boards in the Anza-Borrego State Park speak of the local Native American population consuming mesquite, and Wikipedia, too, says the same about those Cahuilla people of southern California. From what I gather, it is only certain species that have later been invasive?
So… as we finally exit the current ice age we should expect a green Sahara?
I'm not a historian, archeologist, or any sort of relevant expert. But I've long had the pet theory that the Green Sahara is the origin of the Eden Myth. Homo Sapiens origin, lush vegetation, turns to dessert for some reason beyond our comprehension...
Before agriculture, people lived as hunters and (mainly) gatherers. The life of a Hunter-gatherer is, surprisingly, mostly leisure, because of the abundance of food and the low population density. Even Kalahari Bushmen, who had been forced to live in the dessert, were found to average only about 1 1/2 to 2 1/2 hours of productive labor a day in a study [1].
In the bible, God's punishment is [2]:
“Cursed is the ground because of you;
through painful toil you will eat food from it
all the days of your life.
It will produce thorns and thistles for you,
and you will eat the plants of the field.
By the sweat of your brow
you will eat your food
until you return to the ground,
since from it you were taken;
for dust you are
and to dust you will return.”
[1] Stone Age Economics by Marshall Sahlins (https://archive.org/details/StoneAgeEconomics_201611)
[2] https://www.biblegateway.com/passage/?search=genesis%203&ver...
> The results confirm the North African Humid Periods occurred every 21,000 years and were determined by changes in Earth's orbital precession. This caused warmer summers in the Northern Hemisphere, which intensified the strength of the West African Monsoon system and increased Saharan precipitation, resulting in the spread of savannah-type vegetation across the desert. So… as we finally exit the current ice age we s…
If by "Ice Age" you mean period of glaciation - the most recent one ended ~ 11,500 years ago after starting some 120,000 years ago.
We're not currently in an "Ice Age" .. although by general expectation of this cycle we should be slowly moving into one . . . save for this recent rapid rise in C02 and atmospheric insulation increase caused by the most recent century of accelerated human activity.
See the enlarged graphic from the Nature article this thread is about:
https://www.nature.com/articles/s41467-023-41219-4/figures/1
or the full original paper:
https://www.nature.com/articles/s41467-023-41219-4
> ... we should expect a green Sahara?
Well, as noted we've rather changed the system parameters a fair bit, it's difficult to know what to expect where anymore other than a general increase in the amount of trapped energy at the lowest sea | land layers globally.
It's enough energy to eventually tip the otherwise periodically stable climate cells into all manner of not seen before new redistributions of climate activity.