We’ve got atmospheric temperatures shown at the top, shown in blue, and the atmospheric concentration of carbon dioxide (CO2) sown in green.
The creator of this graphic claims that the data came from a “Vostok” ice core operation, from data built on the supposition that a scientist (or group of scientists) can accurately assess both the temperature and carbon dioxide (CO2) content of the earth’s atmosphere 420,000 years ago by measuring chunks of ice extracted in Antarctica.
In January 1998, a collaborative ice-drilling project between Russia, the United States, and France at the Russian Vostok station in East Antarctica yielded the deepest ice core ever recovered, reaching a depth of 3,623 m. Ice cores are unique with their entrapped air inclusions enabling direct records of past changes in atmospheric trace-gas composition. The Vostok ice core reached back 420,000 years and seemingly revealed several past ice ages.
As we can see from the graph made from their data, about 25,000 years ago the air temperatures indicated by Vostok ice core were about 10 degrees Celsius colder than current day. That’s 50 degrees Fahrenheit colder. Which suggests that the earth was largely covered with ice, near the end of what many scientists believe was our most recent ice age.
The Vostok ice core data suggests (to me, at least) several ice ages:
One lasting from 110,000 BC until about 20,000 BCE;
One lasting from about 225,000 BC until about 140,000 BCE;
One lasting from about 300,000 BC until about 240,000 BCE;
And the earliest one indicated by the Vostok ice cores, lasting from about 360,000 BC until about 330,000 BCE.
In between those ice ages, the temperature seems to have increased to a level higher than our current day temperature, for a relatively short period of time.
Here’s the Vostok chart once more, for reference.
This chart makes it appear that variations in atmospheric CO2 and atmospheric temperatures happened at the same exact moment in time, but the graph may be a bit misleading in that regard. Yes, the CO2 levels rose and fell in a similar pattern — but the changes in CO2 levels actually happened about 800 years after the temperature changes, according to the Vostok ice cores, and other similar ice cores.
Scientists cannot easily explain this strange situation. Anyone with any sense would conclude that — if the CO2 increases and decreases happened 800 years after the corresponding temperature increases and decreases — then the CO2 could obviously not be the cause the temperature increases or decreases, but may have been caused by the temperature increases.
Scientists, especially “climate scientists,” cannot easily explain this data because they really want to believe that additional CO2 in the atmosphere causes the earth’s temperature to increase. When the data doesn’t match their preconceived notions, scientists do what they have done for centuries: they concoct a complicated theory to try and explain why the data looks wrong.
Here’s a little quote from the website, RealClimate: Climate Science from Climate Scientists, taken from an article by guest contributor Jeff Severinghaus, Professor of Geosciences at Scripps Institution of Oceanography.
From studying all the available data (not just ice cores), the probable sequence of events at a termination goes something like this. Some (currently unknown) process causes Antarctica and the surrounding ocean to warm. This process also causes CO2 to start rising, about 800 years later. Then CO2 further warms the whole planet, because of its heat-trapping properties. This leads to even further CO2 release. So CO2 during ice ages should be thought of as a “feedback,” much like the feedback that results from putting a microphone too near to a loudspeaker.
In other words, CO2 does not initiate the warmings, but acts as an amplifier once they are underway. From model estimates, CO2 (along with other greenhouse gases CH4 and N2O) causes about half of the full glacial-to-interglacial warming.
But… we have warmings… and we have coolings.
As we notice in the Vostok graph, the temperature of the earth climbed rather quickly (5,000 years) at the end of each ice age, and then about 800 years later, the CO2 began climbing as well. But when the CO2 was at its highest height, the earth’s temperature had already begun falling, and continued falling slowing for thousands of years.
How, then, did the temperature fall? When the atmosphere was chock full of CO2, the “greenhouse gas”? Suddenly, the CO2 lost all its magic warming powers. Professor Severinghaus doesn’t attempt to try and explain the ice age cooling process in his article. (More of the “currently unknown processes,” perhaps?)
A friend of mine explains it this way:
Let’s review the basic “global warming” hypothesis, and see where it fails to meet a standard of proof worthy of general academic acceptance — let alone worthy of reformulating the entire global energy economy around.
In the case of anthropogenic (human-caused) global warming, the basic hypothesis is that excess man-made greenhouse gases (primarily CO2 from burning fossil fuels) are accumulating at unprecedented levels and dangerous rates. These greenhouse gasses are trapping heat that would otherwise be radiated into space, and are causing the entire atmosphere, oceans, and thus the surface temperature of the earth to steadily warm. Over time, according to the hypothesis, this will cause great disruption in global climate, rising of sea levels through melting of existing glaciers and ice caps, destruction of habitats for wildlife, chaos, mass starvation, endless dust bowls, monster storms. In the end, Earth turns into a molten hell like the planet Venus.
Pretty scary, but basically a good testable hypothesis so far. In order to prove this hypothesis, you’d need to show a few things. Like, the earth is actually warming and at an otherwise unexplainably accelerated rate it. (It isn’t even warming, and hasn’t for 18 years now, let alone at an accelerated rate.) You’d need to show you understood all or most of the biggest contributing natural mechanisms that might otherwise impact warming, eliminate them as causes, and link your observed warming effects solely to excess man-made greenhouse gas production. And you’d need to be able to accurately predict the amount of that warming over, say, the next decade or two as a function of those man made CO2 levels.
It has now been over 20 years since the first doomsday predictions of global warming started to accumulate and gain popular political momentum. While it is true CO2 levels have been steadily increasing, atmospheric temperatures actually have not. According to satellite measurements, there’s been no net global warming since approximately the late 1990s — despite increasing levels of CO2.
It turns out there are other greenhouse gases we don’t hear talked about much. Like methane from plant decomposition and intestinal distress of animals (and certain humans).
And… water vapor.
Read Part Four, tomorrow…
Bill Hudson founded the Pagosa Daily Post in 2004 in hopes of making a decent living writing about local politics. The hope remains.