As little as 6,000 years ago, the vast Sahara Desert was covered in grassland that received plenty of rainfall, but shifts in the world's weather patterns abruptly transformed the vegetated region into some of the driest land on Earth. A Texas A&M university researcher is trying to uncover the clues responsible for this enormous climate transformation – and the findings could lead to better rainfall predictions worldwide.
Robert Korty, associate professor in the Department of Atmospheric Sciences, along with colleague William Boos of Yale University, have had their work published in the current issue of Nature Geoscience.
The two researchers have looked into precipitation patterns of the Holocene era and compared them with present-day movements of the intertropical convergence zone, a large region of intense tropical rainfall. Using computer models and other data, the researchers found links to rainfall patterns thousands of years ago.
"The framework we developed helps us understand why the heaviest tropical rain belts set up where they do," Korty explains.
"Tropical rain belts are tied to what happens elsewhere in the world through the Hadley circulation, but it won't predict changes elsewhere directly, as the chain of events is very complex. But it is a step toward that goal."
(Score: 0, Insightful) by aristarchus on Saturday December 03 2016, @04:15AM
Two possibilities:
One: It was Tropical because God had not yet divided the light from the dark, on the first Day, which was already quite light or he couldn't have seen what he was doing . . .(actually, that explains a lot, even jmorris!). This is the Young Earth Moron explanation. (Did you just see aristarchus mock religion? Did you?)
Or Two: The Sahara was tropical because it lay between the two tropics of Cancer and Capricorn, which, by the way, it still does? So what is at issue here? (No, I did not RTFA! Nobody else does, why should I? Eh? I am Tropical to you! Ha Ha! )
(Score: 0, Troll) by Anonymous Coward on Saturday December 03 2016, @05:11AM
Because nobody makes an ass of themselves like you do. Perhaps a step in the right direction would be for you to actually read the comments you respond to like most other folks on this site do.
(Score: 0, Troll) by aristarchus on Saturday December 03 2016, @06:13AM
Umm. Frost Piss? There were no comments to respond to! What are you talking about? I would really like to understand you, AC, but you are making it most difficult. All I can say now is that I hope a male camel finds your mother in a compromised position.
(Score: 2) by Gaaark on Saturday December 03 2016, @04:51PM
and poops on her? :)
--- Please remind me if I haven't been civil to you: I'm channeling MDC. ---Gaaark 2.0 ---
(Score: 3, Funny) by Hyperturtle on Saturday December 03 2016, @02:19PM
Oh, I was told that the deser itself intelligently created, and was located between the tropics of Cancer and Capricorn, because the chimeric (I'm trying to tie in the Capricorn here without getting goofy with astrology to explain the latter) dinosaur overlords (whose rule ended about 6001 years ago in a sudden and quite unexpected flash of light from the sky)--were actually serious about farming and smoking the good parts of the plants (hence the former).
They drained the swamps, used synthetic fertilizers (having not found any mammals yet to cover the land in BS) planted cash crops like hemp and poppies, and ended up turing that area into an arid, cancer causing (tobacco was a cash crop, too) desert of only junk food oasises. The desserts of the deserts, they called it. Very profitable to addict your customers; the problem was that the farmers were users as well.
So, it is of no surprise when then they all got too big and fat. And so they died when they were spaced out and something came out of space. [*documented in the historical allegory known as Airplane] The big thing of light was probably related two of these things: a fungal based cash crop later determined to be manna from the heavens, and an alien spaceship suffering from a hard landing which was called a space arc, from how it was perceived to enter and how it was later documented when that flood from the impact that drained what was left of the Sahara finished the swamps for good, leaving no ruling party from the dinosaurs left to continue with the status quo.
That the arc itself released a bunch of mated pairs of mammals upon crash landing and sealed their fate; the animals ate what was left in all of the convenience stores, grazed the grasslands to nothing and them moved out of Africa to populate the rest of the world, leaving the dinosaurs with just cartons of cigarettes and twinkies. This is enough for some folks, we can see how evolution has selected for this.
To lend credence to this, note that a similar modern-day example can be seen in places like Texas--big, filled with oil, food deserts in real deserts they call suburbia, and a few folks that too big and fat that live throughout the deserts. I am not sure about the arc having a modern day precedent there, but they do have walmart, where the progeny of such historical relics like those overly sized specimens can still be found grazing today; twinkies are known to have a long shelf life.
Also, none of this is wrong because we can't prove a falsehood so I cannot be proven false. Please don't encourage me to think otherwise, because I am happy living in my fantasy world where dinosaurs farmed psychedelics before space mammals landed and gave us steaks.
(Score: 1, Informative) by Type44Q on Saturday December 03 2016, @04:20AM
That's easy: goats. Next question?
(Score: 2) by Dr Spin on Saturday December 03 2016, @07:36AM
Exactly. Goats. And camels. They don't just eat the grass - they pull up the roots to make sure it won't grow back.
Warning: Opening your mouth may invalidate your brain!
(Score: 1, Interesting) by Anonymous Coward on Saturday December 03 2016, @04:54PM
No, goats do not pull up grass by the roots. I have a herd of 24 goats and there's plenty of grass in their pasture. Goats are browsers https://en.wikipedia.org/wiki/Browsing_(predation). [wikipedia.org] I think you're thinking of sheep.
(Score: 0) by Anonymous Coward on Saturday December 03 2016, @11:36PM
Goats and camels... The two animals most closely associated with Muslims. Coincidence that the Sahara was turned into a wasteland? Ecological terrorism more like it.
(Score: 0) by Anonymous Coward on Saturday December 03 2016, @09:02AM
Overgrazing by cattle could even be a valid reason why this changed. It is even a process that is currently going on (the Sahara is still increasing its size). It is a gradual effect where soils become dryer (less absorption of rain water), less plants that transport water from the soil into the air and washout of nutrients by the non-absorbed rain.
(Score: 3, Informative) by Runaway1956 on Saturday December 03 2016, @10:36AM
Yes, cattle - but the people who live in and around the sahara are traditionally sheep and goat herders. For the most part, at least. And, camel jockeys. You don't find a lot of cowboys around the Sahara.
Here in the US, overgrazing by cattle has happened, but our dust bowl is attributed to farmer's plows. Likewise, in Arizona, the land could and did support a lot of flora and fauna, until those plows tore the ground up. It's possible that the Sahara got it's start when more and more people discovered agriculture. Chop the ground, kill the root networks, watch the ground dry, then blow away. It's a beautiful formula, isn't it?
Abortion is the number one killed of children in the United States.
(Score: 1) by Type44Q on Saturday December 03 2016, @01:07PM
Nodded down by the uninformed assuming I was trolling?? It's well understood that overgrazing played the largest part in the desertification of the Sahara, so whoever modded me down... now would be the time for some self-realization [i.e. that you're a fucking idiot]. ;)
(Score: 0) by Anonymous Coward on Saturday December 03 2016, @04:23PM
To be fair your answer was short and comical sounding. Undoubtedly more than goats happened, I thought it was understood that over farming is what happened? (includes goats)
(Score: 3, Interesting) by HiThere on Saturday December 03 2016, @08:00PM
That's the traditional answer, but the evidence is scant. Goats *do* tend to eat young trees, and thus kill off forests and scrub, but that doesn't hurt grass. And the time period doesn't match herds of goats being protected by humans, so one might ask why carnivores didn't keep them in check. It's just as likely that the arrow of causation points the other direction: The land turned into a desert, so the only mammals that could live, even around the fringes, were goats (and camels).
Also, the traditional story ignores the role of sheep, if you assume that over grazing was the cause of desertification. Sheep are a much more reasonable culprit. But assuming that overgrazing was the cause is a bit presumptive when there's no real evidence. That overgrazing degraded an already inhospitable land *is* clear, but it's not at all clear that this was what originally caused the land to become inhospitable.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: -1, Troll) by Anonymous Coward on Saturday December 03 2016, @04:29AM
&nigger;
(Score: 2) by frojack on Saturday December 03 2016, @05:50AM
The two researchers have looked into precipitation patterns of the Holocene era
Rainfall for something that long ago has got to be guesswork?
Find a petrified forest, guess how much rain?
No, you are mistaken. I've always had this sig.
(Score: 2) by Runaway1956 on Saturday December 03 2016, @10:39AM
Yeah - that's what I was thinking too. I really think that a lot of our so-called experts are goofy bastards who sit around trying to imagine stuff while getting paid. After a lifetime of applying for grants, new people think the old bastard is an expert, so they believe the silly shit he spouts.
Abortion is the number one killed of children in the United States.
(Score: 1) by khallow on Saturday December 03 2016, @05:41PM
Rainfall for something that long ago has got to be guesswork?
Lakes and rivers are often around that long. Look at silt deposits in them. Something like the Nile River probably has silt deposits going back millions of years.
(Score: 2) by HiThere on Saturday December 03 2016, @08:04PM
One can also attend to the kinds of trees, and the thickness of their growth rings. It's not guesswork even if it's not perfect. (Silt deposits also have their non-weather based variations, but again it's largely weather. Etc.) And I'm sure there are other measures that I don't know about because I'm not a specialist in that area, but silt deposits and growth rings are known even by the intelligent layman.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 1, Offtopic) by aristarchus on Saturday December 03 2016, @06:16AM
How the hell, OK, I am not really surprised, did I get an "overrated" mod, when the only other mod was "troll"? Should I be getting a message?
(Score: 2) by Azuma Hazuki on Saturday December 03 2016, @06:50AM
Can you ever GET a -1/Overrated without first getting positive modification? Something's whacky here...
I am "that girl" your mother warned you about...
(Score: 3, Funny) by aristarchus on Saturday December 03 2016, @07:30AM
My point exactly. Am I being paranoid? I have been being paranoid, lately. But I thought that SoylentNews was a safe zone of support and fluffies. I could be wrong.
(Score: 2) by Runaway1956 on Saturday December 03 2016, @10:43AM
Yes, you're paranoid. And, yes, we are all out to get you. I don't know anything about those fucking fluffies you're talking about. Someone around here probably killed them and ate them. If you want support, there's a group that meets here alongside AA and NA after we all go home. Paranoids Anonymous, I think they call themselves. Watch out for Big Ben though - he'll hit on you, and hates to hear the word "no". 'Course, you may like Ben.
Abortion is the number one killed of children in the United States.
(Score: 2) by Phoenix666 on Saturday December 03 2016, @03:22PM
Are "fluffies" a naughtier version of "furries?"
Washington DC delenda est.
(Score: 2) by Gaaark on Saturday December 03 2016, @04:55PM
You're thinking of 'fluffer', lol.
--- Please remind me if I haven't been civil to you: I'm channeling MDC. ---Gaaark 2.0 ---
(Score: 2) by Runaway1956 on Saturday December 03 2016, @07:55PM
I'm not real sure, but I think the fluffies and bronies are related. I'm not part of the culture, so I get confused.
Abortion is the number one killed of children in the United States.
(Score: 0) by Anonymous Coward on Saturday December 03 2016, @04:25PM
Do you ever get tired of being an asshole? Don't worry, rhetorical question.
(Score: 2) by Azuma Hazuki on Saturday December 03 2016, @08:00PM
From what I've seen of him, no, no he doesn't. And unlike any sane human being, who would stop and think "y'know if perfect strangers are calling me an asshole maybe I should reflect on my behavior," he'll simply take it as validation.
Rebels-without-a-clue aren't funny or endearing after age 14 or so :/
I am "that girl" your mother warned you about...
(Score: 0) by Anonymous Coward on Saturday December 03 2016, @04:17PM
I had something weird like that happen when I modded someone else, it didn't appear to change but still said I had modded the comment :/
(Score: 2) by q.kontinuum on Saturday December 03 2016, @05:29PM
Probably because "rating" can refer to your posts current score, not only to the scores awarded by others? So, if your post is rated "0" someone could still consider this too high.
(I don't know which exact post you are talking about, don't have any opinion on that, just commenting on the logic of the rating system as I understand it)
Registered IRC nick on chat.soylentnews.org: qkontinuum
(Score: 1, Insightful) by Anonymous Coward on Saturday December 03 2016, @06:52AM
maybe imagine a oil guzzeling society that needs fuel to fertilize crops,
build housing, transport, build places of worship, cook food and then they also
use the same fuel for housing and tools.
now replace above "oil" with "wood" and imagine how the lush sahara
forests were bleed dry and then how the gazillion missing photosynthesizing
organisms stopped retaining water with small shades called leafs,
making oxygen, perspiring water, cooling the air ... making the weather.
voila, crazy idea .. the ancient egyptians made the sahara by chopping down the
forest?
(Score: 0) by Anonymous Coward on Saturday December 03 2016, @07:03AM
hey! maybe we can get kevin costner from rapa-nui to play a
a agyptian aristocrat-philosopher that sees the warning signs when the desert
starts to encroach on his egypten summer retreat far from the london-smog-like
cairo?
maybe we can make a popular multi-part plot were he then is reborn in china and sees
the semi ancient chinese chop down huge old trees to build their famous world
circumventing "treasure fleet" as captain sinbao-o with his warnings
coming true after the weather becomes violent because of missing trees
and lighning strikes the throne of the chinese emperor and the subsequent ejection
of the emperor because of these bad omens leading to china once again retreating into its
now treeless self? ^_^
(Score: 2) by Runaway1956 on Saturday December 03 2016, @11:04AM
I've always blamed the Ethiopians, but, at this point, what difference does it make?
Abortion is the number one killed of children in the United States.
(Score: 0) by Anonymous Coward on Saturday December 03 2016, @07:08PM
Lol, no. The process of desertification started about 6000BC [sciencedaily.com]. The oldest signs of bronzemaking in the fertile crescent is about 4500BC and much later (3000BC) in Egypt.
People without metal tools don't clear cut forests.
(Score: 2) by HiThere on Saturday December 03 2016, @08:08PM
No, but goats *do* kill forests by eating the young trees. However the summary said it was grassland, and that lets out the wood burning civilization theory as well as "the goats ate the forest".
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: -1, Flamebait) by Anonymous Coward on Saturday December 03 2016, @07:15AM
According to a close reading of the Bible, the earth is 6000 years old. And it started with two humans living in a tropical paradise; it seems they mucked things up.
Really, you could've gotten this info from Sarah Palin.
(Score: 3, Informative) by WalksOnDirt on Saturday December 03 2016, @08:12AM
The world was warmer 6000 years ago. Warmer worlds have more rainfall, and it just so happened that the extra rain that fell on the Sahara was more important than the extra evaporation. It's cooler now and it has dried up. I don't know why it hit the Sahara so hard; climate is very complicated.
No, human caused warming probably won't have the same effect.
(Score: 0, Informative) by Anonymous Coward on Saturday December 03 2016, @11:09AM
QED
(Score: 2) by Azuma Hazuki on Saturday December 03 2016, @08:02PM
Islam hasn't even been around 1500 years you complete dipshit.
I am "that girl" your mother warned you about...
(Score: 0) by Anonymous Coward on Saturday December 03 2016, @08:02PM
Mudhammed wasn't even around 6000 years ago, dummy. Or Moohamed, or whatever the bastard's name is.
(Score: 5, Insightful) by datapharmer on Saturday December 03 2016, @02:57PM
This is nothing mind-blowing. As an anthropologist I can answer you definitively: people. People caused this and people will make more deserts. If you follow the history of people our oldest civilizations are all in what were lush forests and what are now deserts. From Egypt and Mesopotamia to Lesvos Greece to Easter Island to the British Isles to even more recently areas of North Korea, Northeastern Brazil and the U.S. Southwest (the Colorado river delta was once lush and green, but all the water was diverted to cities so it now dries up before reaching the ocean). Every place people go they chop down the forests, exploit the soils and eventually end up with a desert.
(Score: 3, Informative) by fliptop on Saturday December 03 2016, @05:22PM
Is it something that's not being considered? It's a process that takes thousands of years [wikipedia.org]:
To be oneself, and unafraid whether right or wrong, is more admirable than the easy cowardice of surrender to conformity
(Score: 3, Interesting) by Runaway1956 on Saturday December 03 2016, @08:07PM
I've referred to that a number of times, but never used it's proper name. The earth has naturally occurring ice ages, but everyone has forgotten that the earth is - right now - coming out of an ice age. Climate changes, over time. Mankind has seen and recorded a few thousand years of climate, and he believe that he know all there is to know. But, precession. You got it. Given time, most of the earth will be tropical forest again. The lowlands will be flooded, the inland seas will probably refill, the uplands will support our current lowland flora and fauna, and more. The only thing that never changes is, everything keeps on changing. Mankind will adapt, or die.
Abortion is the number one killed of children in the United States.