Posted on 06/03/2015 7:16:51 AM PDT by SeekAndFind
This story is actually quite fascinating and it obviously has something to do with changes in the climate, but just how to explain it all remains a subject of contention. You would think that increasing temperatures would make things worse in the deserts of the world, but in a rather counterintuitive instance of planet watching, it appears that the Sahara desert may actually be shrinking.
A few thousand years ago, a mighty river flowed through the Sahara across what is today Sudan. The Wadi Howarnow just a dried-out riverbed for most of the yearsustained not just fish, crocodiles, and hippopotamuses, but also agriculture and human settlement. As late as 1,000 B.C., a powerful fortress stood on its shores. But then the Sahara dried out, turning from a green savannah into an inhospitable desert. The culprit: climate change. According to desert geologist Stefan Kröpelin, who has studied geological data for the eastern Sahara going back 6,000 years, the desert spread as temperatures dropped. Global cooling meant that the air had less capacity to hold moisture from the oceans, leading to fewer rains and more arid climes.
Now, that same process is happening in reverse. As temperatures rise, the Sahara and other dry areas are greening on the edges. Ive been studying the Sahara for 30 years and can definitely say that its getting greener, says Kröpelin, who specializes in desert archaeology and climate history at the University of Cologne. Where there used to be nothing but desert, he says, there is now not just grass but shrubs and acacia trees–and he has the photos from 30 years of extensive field study to prove it. The nomads are taking their camels to graze in areas where theyve never been able to graze before. Satellite data showing more green on the southern edge of the Sahara also bear him out. “There are always winners and losers if weather patterns change,” he says. But as a general rule, warmer temperatures inevitably mean that the air picks up more moisture from the oceans, which will lead to more rainfall. If you look at the geological records in the Sahara, there have been repeated periods where the Sahara was greener when temperatures were warmer than today.
So the desert was originally created around six thousand years ago under this theory. (Clearly caused by the hydraulic fracturing taking place in the Garden of Eden. Darned industrialist snakes…) But now the warmer temperatures are causing more rain at the edges of the desert? The subject is endlessly fascinating. Over the years I’ve heard all sorts of theories being tossed out in the scientific community regarding the planet’s biggest, baddest desert. One of the most recent ones – and for some reason I thought this was generally accepted, but perhaps not – is that the planet’s orbital tilt drifts over time. Around the same time period they’re talking about in this article, the tilt began to change, shifting the planet into a less inclined tilt from then until now.
The widely-held belief is that the Sahara dried up due to a change in the Earths orbit, which affects solar insolation, or the amount of electromagnetic energy the Earth receives from the Sun. In simpler terms, insolation refers to the amount of sunlight shining down on a particular area at a certain time, and depends on factors such as the geographic location, time of day, season, landscape and local weather.
Climate scientist Gavin Schmidt, of NASAs Goddard Institute for Space Studies, explained that around 8,000 years ago, the Earths orbit was slightly different to how it is today. The tilt changed from around 24.1 degrees to the present-day 23.5 degrees.
Additionally, the Earth had its closest approach to the Sun in the northern hemisphere (with) summer in August, Schmidt said. Today, that closest approach is in January. So, summertime in the north was warmer back then than it is now.
Earlier theories speculated that there was a growing “rain shadow” effect caused by the continually rising Himalayan Mountains, disrupting weather patterns and stopping the rainfall in some areas. Still other have said that eccentricities in the earth’s orbit around the sun (a different consideration than the orbital tilt) have periodically thrown things off kilter in either direction which also contributed to the growth or recession of major deserts.
In either event, even if we can’t nail down exactly what’s causing it and to what degree the effects are felt, this must at least be some good news for farmers and herders in Africa. Party on, folks.
I don’t like the whole climate change debate in general. I think the science gets very lost in the partisanship. But I have always wondered whether the scientific community presenting the case for climate change has not underestimated the ways in which the planet will compensate for higher temperatures in just the way that this article is arguing. And it’s not just the Sahara. There are huge areas of subarctic tundra where tree growth is exploding.
So high carbon leads to warmth, warmth leads to plant growth, plant growth soaks up excess carbon and the warming moderates again.
I don’t like the whole climate change debate in general. I think the science gets very lost in the partisanship. But I have always wondered whether the scientific community presenting the case for climate change has not underestimated the ways in which the planet will compensate for higher temperatures in just the way that this article is arguing. And it’s not just the Sahara. There are huge areas of subarctic tundra where tree growth is exploding.
So high carbon leads to warmth, warmth leads to plant growth, plant growth soaks up excess carbon and the warming moderates again.
Huge self adjusting systems? Sounds right to me. It’s a natural.
The earth’s climate is always changing, but those changes have nothing to do with molecular level changes in CO2 produced by human activity. Why did the Sahara dry up 6,000 years ago when human activity at the time added little to the global levels of CO2? The sun, the oceans, variations in the tilt of the earth’s axis and volcanic eruptions have far more to do with alterations in climate than any amount of CO2. The big lie is that human caused increases in CO2 resulting in global warming is the only significant cause of climate change.
“Its a natural.”
What do you mean nature? Why, that implies something other than our self-appointed gods control the Earth. Can’t have that!
Before you know it, the people will be worshiping God...
Humans debating global warming is like three mites claiming to push the elephant they are hitching a ride on.
“Now, that same process is happening in reverse. As temperatures rise, the Sahara and other dry areas are greening on the edges. “
Another ‘warm globally, cool locally’ alert!
You can say that again!
2015 Southern Ocean Iceberg Forecast | Mini Ice Age 2015-2035
https://www.youtube.com/watch?v=T4aVclYH5xI
Earth is Doomed to Decades of Cooler Temperatures
http://drsircus.com/world-news/earth-is-doomed-to-decades-of-cooler-temperatures
June all-time record low shattered in Boston
http://iceagenow.info/2015/06/june-all-time-record-low-shattered-in-boston/
Norway snow driver Never experienced anything like this before
http://iceagenow.info/2015/06/norway-snow-driver-never-experienced-anything-like-this-before/
Ive been in this job for many years, and in my time we have never had to close because of bad weather in June, but today we had no choice, says Tor Helge Tveit, who has coordinated plowing service on Hardangervidda many years.
Norway School bus blown off road in snowstorm
http://iceagenow.info/2015/06/norway-school-bus-blown-off-road-in-snowstorm/#more-16503
Blizzards in Scotland
http://iceagenow.info/2015/06/blizzards-in-scotland/
And all this heat is making the glaciers grow!
http://www.iceagenow.com/List_of_Expanding_Glaciers.htm
A clear easy to understand from lush to desert.
Now let’s move to the California desert. Dingbat Brown is running around on the global warming witch hunt and California has no water. Maybe he should try and increase global warming along the coast to increase rainfall. Simple idea and positive results.
“Before you know it, the people will be worshiping God...”
its awkward.. but it’s inevitable!
OH NO THE GREEN GRASS, LUSH VEGETATION AND WATER ARE CREEPING IN ON THE CAMELS.
WE CAN'T HAVE THAT.
WE NEED TO SEND MORE MONEY TO THE GLOBAL WARMING SCIENTISTS SO THEY CAN COME UP WITH A SOLOUTION.
NEXT THING YOU KNOW WE WILL BE CALLING THE CAMELS LLAMAS. OH YEAH RIGHT, LLAMAS AND CAMELS ARE RELATED.
Very cool and unexpected by me. I will say, the Earth has her own buffer systems to maintain world temperatures in a fairly well known range. We know the temperatures at the height of the ice ages and the temperatures for the warming periods between ice ages.
It is nature folks. Man has a negligible impact on the climate or the direction or magnitude of long term trends in world temperature changes.
Amazing how an entire propaganda machine has spun that fact on its head. I can’t wait until the theory of anthropomorphic global warming from CO2 emissions is so widley debunked that it is common knowledge to every layman in the nation.
It would be funny if the changes that scientists make to combat global warming would cause an ice age!
Note: this topic is from 6/03/2015. Thanks SeekAndFind.
Note: this topic is from 6/03/2015. Thanks SeekAndFind.
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