Scientists Prove Clear Link Between Deforestation and Local Drop in Rainfall (theguardian.com) 16
For the first time researchers have proven a clear correlation between deforestation and regional precipitation. Scientists hope it may encourage agricultural companies and governments in the Amazon and Congo basin regions and south-east Asia to invest more in protecting trees and other vegetation. From a report: The study found that the more rainforests are cleared in tropical countries, the less local farmers will be able to depend on rain for their crops and pastures. The paper, published in the journal Nature, adds to fears that the degradation of the Amazon is approaching a tipping point after which the rainforest will no longer be able to generate its own rainfall and the vegetation will dry up. People living in deforested areas have long provided anecdotal evidence that their microclimates became drier with lower tree cover. Scientists already knew that killing trees reduces evapotranspiration and thus theorised this would result in lower local rainfall.
The team at Leeds University have now proven this using satellite and meteorological records from 2003-17 across pantropical regions. Even at a small scale, they found an impact, but the decline became more pronounced when the affected area was greater than 50km squared (2,500 sq km). At the largest measured scale of 200km squared (40,000 sq km), the study discovered rainfall was 0.25 percentage points lower each month for every 1 percentage point loss of forest. This can enter into a vicious cycle, as reductions in rainfall lead to further forest loss, increased fire vulnerability and weaker carbon drawdown. One of the authors, Prof Dominick Spracklen of the University of Leeds, said 25% to 50% of the rain that fell in the Amazon came from precipitation recycling by the trees. Although the forest is sometimes described as the "lungs of the world," it functions far more like a heart that pumps water around the region.
The team at Leeds University have now proven this using satellite and meteorological records from 2003-17 across pantropical regions. Even at a small scale, they found an impact, but the decline became more pronounced when the affected area was greater than 50km squared (2,500 sq km). At the largest measured scale of 200km squared (40,000 sq km), the study discovered rainfall was 0.25 percentage points lower each month for every 1 percentage point loss of forest. This can enter into a vicious cycle, as reductions in rainfall lead to further forest loss, increased fire vulnerability and weaker carbon drawdown. One of the authors, Prof Dominick Spracklen of the University of Leeds, said 25% to 50% of the rain that fell in the Amazon came from precipitation recycling by the trees. Although the forest is sometimes described as the "lungs of the world," it functions far more like a heart that pumps water around the region.
Revisit middle school earth science (Score:2)
And study the water cycle. Should be obvious why removing trees, bulldozing green space, and paving it over so rainfall short circuits the ground and flows into the ocean via rivers leads to local and regional drought. But hey people need strip malls
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next they will find out it also helps prevent massive flood damages
Not suprising (Score:5, Interesting)
It's not that they don't know (Score:3)
If the reduced rainfall does not affect them personally, nothing will change.
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They don't care because no one else cares. Those warning of severe ramifications are forced to drink the hemlock tea time and time again. And then the whole thing falls apart, but the money has been made, the wealthiest have made their redoubts, and the best you get is the odd king losing his head.
Humanity, with a brain that is amongst the complex organizations of matter in the universe, is still basically a bunch of angry, masturbating chimpanzees.
Living Things are made of water (Score:5, Interesting)
Humans are around 60% water, trees are around 50%. Living things constantly take in and give off water.
If you cut down 4 ton of trees, there goes about 2 ton of water that acted like a battery, taking in water when it was wet and giving off water when it was dry. That water it gives off becomes rain.
Worst of all is that if you cut down 4 tons of trees, plant 10 lbs of seeds, and every year you harvest 1 ton of food, that is removing 1 ton of water from the farm ground and shipping to cities, most of whom dump it in sewage which ends up in the ocean.
Not hard to understand how if you remove 2 tons of water right away and then remove another ton every year, you are going to have a problem.
Dry states should not farm, no matter how much sunshine they gate.
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If you get desperate, mountains are easy to build, it's just a pile of rock. And they make the air cry and you get rain.
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Cutting timber to build houses is a trivial amount of deforestation. Most deforestation is because of clearing land to farm cattle or grow food for cattle.
Meat is the problem. Just stop eating meat.
Oh no. (Score:2)
It looks great and the slash burning is truly very good for breathing, that's history there, son, alive in yer lungs. All those tractors rigs kept to 3rd world noise and pollution standards adding value to the roads they destroy an
Won’t make a difference (Score:3)
Something like this could change farming practices in the modern world, where farming companies want their land to be productive for decades. Those big agribusinesses? They might be willing to plant a bunch of trees and wait for them to grow, if it improves crop yields.
It's a desert, because it never rains (Score:2)
And it never rains, because it's a desert.
New? (Score:4, Interesting)
I remember hearing a report some time ago, I believe on NPR. that they'd found that the American Southwest was deforested by the Native Americans there hundreds of years ago and it became a desert as a result. Too much use of wood, for construction and cooking fires.
There were also similar stories told of Easter Island.
My son-in-law once told me that in Nebraska the farmers consider trees to be in competition with their crops for water, and are therefore eager to see the trees go. However trees don't export water the way crops do. We never learn.
Sounds familiar ... (Score:1)
I am getting the distinct impression that this was in the science and geography textbooks back in the 1980s.
Even can smell the mimeograph machine.