(Source) |
(15 million years ago, atmospheric CO2 levels in the range of 400-500 parts per million produced Antarctic melt resulting in substantial sea level rise. The above image shows the estimated location of the U.S. eastern coastline at the time. Image source: Colorado Geosystems.)
“The MMCO [Middle Miocene Climate Optimum] was
ushered in by CO2 levels jumping
abruptly from around 400ppm to 500 ppm, with global
temperatures warming by about 4°C and sea levels rising about 40m (130 feet) as
the Antarctic ice sheet declined substantially and suddenly. ” — Skeptical
Science
Human beings have never seen atmospheric CO2
values that are so high as they are today. They significantly predate our
species — even preceding our distant relative Australopithecus
by about 7 million years. And weather and climate conditions to which
we are not adapted — either as individuals or as a civilization — are well on
the way as atmospheric CO2 levels are ramping up into the lower range of those
last seen during the Middle Miocene of 14-16 million years ago at 404 parts per
million during 2016.
For the first 11 months of the year, 2016
atmospheric carbon dioxide concentrations exceeded those of 2015 by an average
of 3.45 parts per million. With no sign evident that the pace of increase has
slackened — despite a transition to La Nina during the fall — it now appears that the world
is set to experience a 3.3 to 3.5 part per million jump in the atmospheric CO2
measure for this year.
The past two record jumps were 2015 —
with a 3.05 ppm annual increase and 1998 with a 2.93 ppm annual increase. But 2016
now appears set to exceed these two values by a pretty hefty margin.
Such rapid rates of atmospheric carbon dioxide
increase are primarily caused by global fossil fuel burning — which now produces an emission that is more than 100
times greater than all the volcanoes that erupt across the Earth during any
given year. And recent reports have found that US automobile emissions alone equal the amount of
carbon dioxide emitted by the Mount St. Helens eruption every three days. This is a
heavy insult to the Earth’s climate system. One that is unprecedented for
millions of years.
[Read more here]
A 40 metres rise in sea levels, guys. 40 metres!
And yet there are still the Trumpistas living in their climate denialist
loony-tunes universe who want – Dear God! – to encourage the burning of fossil fuels.
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