Hi Alex here. Is climate change really human-made?
There's been a lot of research and reports published over the years and
I don't blame you if you don't want to read it all so here is what we know for sure
in 3 minutes. Let's get drawing! It all started in 1998
when an ice-drilling project was undertaken
in the Russian Vostok Station in Antarctica. The project yielded the
deepest
ice-core ever recovered giving access to ice that was 420,000 years old
at a depth of 3,623 meters.
It supplied data about atmospheric composition
and climate through 4 climate cycles. So here is how it all works:
the formation of the glaciers results from the transformation
of water into ice during this process
which can last thousands of years sediments
air and rocks are stuck into the ice making millions of layers
one above the other in chronological order. Over the time,
the glacier becomes a million page history book
with the last chapter on the top. The deeper you drill
the older the compounds are. The ice core gave access to climate data
including local temperature, precipitation rate, wind strength,
etc.
but also and this is what we are interested in here
the ice core provided direct records of past changes
in atmospheric trace-gas composition thanks to their
entrapped air inclusions. Then it was possible to determine the levels
of carbon dioxide (CO2) and methane
(CH4) at a given time so
here is what global temperature and atmospheric concentrations
of carbon dioxide and methane look like
over for climate cycles 420,000 years
So you can clearly see the four climate cycles
and you also see that they have very similar spikes and patterns
there is clearly a relationship between temperature
carbon dioxide and methane. The upper and lower boundaries
up the three variables are tightly constrained which is typical
a self-regulating system. Our body is also a self-regulating system
and does something similar in a way: when you exercise
your body sweats as a way to regulate its temperature
well on Earth when concentrations of carbon dioxide
and methane go up global temperature
goes up too. Now here is what happened
with the concentration of atmospheric CO2 since 1960:
it increased by about 70 parts per million
that is more than one part per million each year
indicating significant human perturbation in the self-regulating
of Earth since the beginning of the Industrial Revolution
As this concentration is now way
over the upper boundary noted during the last 420,000 years
and as the Earth seems to be a self-regulating system
well we can expect the global temperature
to increase as well and we are already seeing this worlwide.
Since the Vostok research was published
more recent ice cores were performed by the European Project for
Ice Coring in Antractica (the EPICA)
they provided data for the last 800,000 years
and confirmed the findings in Vostok so
as the Intergovernmental Panel on Climate Change simply puts it
in their 2013 report: "human influence on the climate system is clear"
and we can safely say that we human beings
are responsible for climate change
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