by Stockholm University, August 27, 2019 in WUWT/fromNature
34 million years ago the warm ‘greenhouse climate’ of the dinosaur age ended and the colder ‘icehouse climate’ of today commenced. Antarctica glaciated first and geological data imply that the Atlantic meridional overturning circulation, the global ocean conveyor belt of heat and nutrients that today helps keep Europe warm, also started at this time. Why exactly, has remained a mystery.
“We have found a new trigger to explain the start-up of the Atlantic current system during the greenhouse-icehouse climate transition: During the warm climate, buoyant fresh water flooded out of the Arctic and prevented the ocean-sinking that helps power the conveyor. We found that the Arctic-Atlantic gateway closed due to tectonic forces, causing a dramatic increase in North Atlantic salinity. This caused warming of the North Atlantic and Europe, and kickstarted the modern circulation that keeps Europe warm today,” says David Hutchinson, researcher at the Department of Geological Sciences, Stockholm University, and lead author of the article published in Nature Communications.
The team of scientists, from the Bolin Centre for Climate Research, used a combination of geophysical data and climate modelling to show that the freshwater transport through the Arctic-Atlantic gateway plays a critical role in controlling the overturning circulation.
by Scott Denning, August 22, 2019 in LiveSci=nce
Fires in the Amazon rainforest have captured attention worldwide in recent days. Brazilian President Jair Bolsonaro, who took office in 2019, pledged in his campaign to reduce environmental protection and increase agricultural development in the Amazon, and he appears to have followed through on that promise.
The resurgence of forest clearing in the Amazon, which had decreased more than 80% following a peak in 2004, is alarming for many reasons. Tropical forests harbor many species of plants and animals found nowhere else. They are important refuges for indigenous people, and contain enormous stores of carbon as wood and other organic matter that would otherwise contribute to the climate crisis.
Some media accounts have suggested that fires in the Amazon also threaten the atmospheric oxygen that we breathe. French President Emmanuel Macron tweeted on Aug. 22 that “the Amazon rain forest — the lungs which produces 20% of our planet’s oxygen — is on fire.”
Don’t hold your breath
Even though plant photosynthesis is ultimately responsible for breathable oxygen, only a vanishingly tiny fraction of that plant growth actually adds to the store of oxygen in the air. Even if all organic matter on Earth were burned at once, less than 1% of the world’s oxygen would be consumed.
In sum, Brazil’s reversal on protecting the Amazon does not meaningfully threaten atmospheric oxygen. Even a huge increase in forest fires would produce changes in oxygen that are difficult to measure. There’s enough oxygen in the air to last for millions of years, and the amount is set by geology rather than land use. The fact that this upsurge in deforestation threatens some of the most biodiverse and carbon-rich landscapes on Earth is reason enough to oppose it.
by Donna Laframboise, August 23, 2019 in BigPicturesNews
Politicians and government officials like to talk as though it’s possible to stamp out fake news. It isn’t.
Fake news is as old as humanity. After Aristotle incorrectly claimed women had fewer teeth than men, generations of highly educated people believed it.
Rajendra Pachauri was called “the UN’s top climate scientist” by the BBC – and a “Nobel laureate” by the New York Academy of Sciencesmagazine. Neither statement was true.
Pachauri’s doctorate wasn’t in climatology, but in industrial engineering and economics. And the fact that he accepted the 2007 Nobel Peace Prize on behalf of the UN organization he chaired doesn’t make him or any other person affiliated with that organization a Nobel laureate.
Published in 2008 and 2009, these inaccurate statements have never been corrected. In other words, we’re surrounded by fake news. And always will be. Humans are frequently mistaken. Organizations, as well as individuals, post things on the Internet before double-checking.
While media outlets are supposed to be more reliable than your brother-in-law, that seems less true every day. Over the past week, people have shared a CNN headline on Facebook that declares: “The Amazon rainforest is burning at a record rate” (see the screengrab from my own Facebook feed, at the top of this post).
If you click through to the CNN website, you’ll find a few extra words: “…research center says.” But the primary statement is misleading. Which means that millions have been alarmed unnecessarily – including a lovely, smart, young mother of my acquaintance.
Over at the website of National Geographic, a headline falsely declares: Brazil’s Amazon is burning at record rates – and deforestation is to blame. The second half of that assertion is vigorously disputed here.
Why Everything They Say About The Amazon, Including That It’s The ‘Lungs Of The World,’ Is Wrong
Amazon fires: how celebrities are spreading disinformation
The Amazon Is Not Earth’s Lungs: Humans could burn every living thing on the planet and still not dent its oxygen supply
Is Amazon Rainforest Burning At Record Rates? What Is The Way Forward?
Lies, Damn Lies, And Rainforest Fear-Mongering
Annual Amazon farmland burn sets records for international outrage
Amazon fires: What about Bolivia?
Stop Sharing Those Viral Photos of the Amazon Burning
The Three Most Viral Photos of the Amazon Fire Are Fake. Here Are Some Real Ones to Share.
What Satellite Imagery Tells Us About the Amazon Rain Forest Fires
The myth of ecocide: So many lies are being told about the Amazon fires
Why shouldn’t Brazilians burn down trees?
Sugar cane, Palm oil, and Biofuels in the Amazon