In his presentations on global warming, profiteering, prophet Al Gore likes to use a graph similar to the one below from Vostok, Antarctica, ice core to show apparent correlations between temperature and carbon dioxide. When pressed about cause and effect, Gore says the relationship is “complex.”
The scientists working on the Vostok ice core report that temperature changes PRECEDE changes in CO2 concentration by about 800- to 1,300 years. This should not be surprising because temperature has great influence on CO2 solubility in the ocean. Notice that the temperature cycles occur in approximately 100,000 (±20,000)-year intervals. This coincides with the variation in the precession of the Earth’s elliptical orbit around the Sun. Can you think of anything that would make CO2 cycle this way if it were the driver rather than temperature? And what would stop the rise of CO2 if it were the controlling variable?
You may have heard climate alarmists say something like this: “There is more carbon dioxide in the atmosphere today than at any time during the past 650,000 years, based on analyses of the chemical composition of air bubbles entrapped in Antarctic ice over that time.”
That contention relies on an unproven assumption. The assumption is that entrapped bubbles are an accurate measure of the ancient atmosphere. In fact, there is good evidence that, with increasing pressure and time, the bubbles undergo chemical and physical changes which deplete CO2, so it is unlikely that they contain true ancient atmospheric compositions. Furthermore, reconstructions based on ice core bubble composition data disagree with reconstructions from most other proxies.
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