https://cleantechnica.com/2019/04/10/study-finds-earths-atmosphere-is-strongly-sensitive-to-small-changes-in-carbon-dioxide-levels/
[links in online article]
Study Finds Earth’s Atmosphere Is Strongly Sensitive To Small Changes In
Carbon Dioxide Levels
The Potsdam Institute for Climate Impact Research says its latest
computer models reveal that small changes in the level of carbon dioxide
in the atmosphere correlate strongly to periods of higher and lower
average global temperatures. Based on an analysis of ocean sediments, it
says the last time CO2 levels were this high was 3 million years ago
during the Pliocene Era when ocean levels were 60 feet higher than they
are today and both poles were covered in forests.
Breakthrough Based On Analyzing Ocean Sediments
“We know from the analysis of sediments on the bottom of our seas about
past ocean temperatures and ice volumes, but so far the role of CO2
changes in shaping the glacial cycles has not been fully understood,”
says Matteo Willeit of the Potsdam Institute for Climate Impact
Research, lead author of the study now published recently in Science
Advances.
“It is a breakthrough that we can now show in computer simulations that
changes in CO2 levels were a main driver of the ice ages, together with
variations of how the Earth orbits around the sun, the so-called
Milankovitch cycles. These are actually not just simulations: we
compared our results with the hard data from the deep sea, and they
prove to be in good agreement. Our results imply a strong sensitivity of
the Earth system to relatively small variations in atmospheric CO2. As
fascinating as this is, it is also worrying.
“It seems we’re now pushing our home planet beyond any climatic
conditions experienced during the entire current geological period, the
Quaternary, a period that started almost 3 million years ago and saw
human civilization beginning only 11,000 years ago. So, the modern
climate change we see is big, really big even by standards of Earth
history,” says Willeit.
Sea Levels Were Once 60 Feet Higher
The Pliocene was a “proper analogy,” Martin Siegert, a geophysicist and
climate-change scientist at Imperial College London, tells The Guardian.
“The headline news is the temperatures are 3-4º C higher and sea levels
are 15-20 meters higher than they are today. The indication is that
there is no Greenland ice sheet any more, no West Antarctic ice sheet
and big chunks of East Antarctic [ice sheet] taken.”
Co-author Andrey Ganopolski says, “The fact that the model can reproduce
the main features of the observed climate history gives us confidence in
our general understanding of how the climate system works. The
simulations we develop have to be simple enough to allow for thousands
of calculation runs of many thousands of years, and yet have to capture
the critical factors that drive our climate. This is what we have
achieved. And it is confirming how outstandingly important changes in
CO2 levels are for Earth’s climate.”
Jane Francis, director of the British Antarctic Survey, tells The
Guardian, “This is an amazing discovery. They found fossil leaves of
southern beech. I call them the last forests of Antarctica. They were
growing at 400 ppm CO2, so this may be where we are going back to, with
ice sheets melting at times, which may allow plants to colonize again.
We know that is where the change happens first and where it is most
dramatic.”
The Idiocy Of William Happer
Princeton professor William Happer, who is now a science adviser to the
Tramp administration, says carbon dioxide is good for growing plants.
Martin Siegert agrees, pointing out that during the Cretaceous period
100 million years ago, CO2 levels reached 1,000 ppm. Antarctica was 25º
C warmer than today and was covered in great forests.
“If we keep carbon emissions going at the current rate, by the end of
the century we will have 1,000 ppm,” he says. The amount of carbon
dioxide actually fell to 280 ppm prior to the start of the industrial
revolution. That was because all that vegetation removed it from the
atmosphere and sequestered in all those plants that Happer loves so much
and then was buried. “It formed coal seams, gas and oil fields. And what
we have been doing for the last 150 years is digging it all up and
putting it back into the atmosphere. It’s crazy.”
So hooray for William Happer. If we take the long view, there is
absolutely nothing to worry about because the Earth will restore itself
in 40 or 50 million years. Sadly, however, every living thing on the
planet will dead and buried long before then. Let us fervently hope the
next species to preside over the Earth is not as intellectually
deficient as Dr. Happer or else the whole process will begin anew. One
thing we know for sure is that no descendants of William Happer will be
around to celebrate his perspicacity and erudition.
Perhaps on some future date millions of years from now, archaeologists
will unearth a Chevy Suburban or a Ford F-150 and announce the mystery
of why humans failed to survive has been solved. Presumably by then
transportation will no longer rely on fossil fuels and automakers won’t
still be whining about how nobody wants to buy an electric car.
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