ice core

2010 the 9000th Warmest Year

The year 2010 was one of weather extremes due mainly to the transition from El Nino to La Nina. The year has been much touted as the warmest in the last 150 years or at least the warmest since it was cooler. But, looking at a longer perspective, the 10,500 years of our current interglacial period, 2010 was cooler than about 9,000 of those years.

That is the contention of geologist Dr. Don J. Easterbrook. “One of the best ways to look at long-term temperatures is with isotope data from the GISP2 Greenland ice core, from which temperatures for thousands of years can be determined.” By looking at the ratio of oxygen- 16 to oxygen-18, the temperatures at the time snow fell over the glaciers can be determined. “The age of such temperatures can be accurately measured from annual layers of accumulation of rock debris marking each summer’s melting of ice and concentration of rock debris on the glacier.”

Cuffey and Clow

See Easterbrook’s full article here.

Al Gore’s Favorite Graph

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.”

460000-years

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.

Sources:

Jaworowski,Z., Segalstad,T.V. andHisdal,V.,1992, Atmospheric CO2 and global warming: A critical review., Meddelelser 119, Norsk Ploarinstitutt, Oslo.

Mudelsee, M, 2001. The phase relations among atmospheric CO2 content, temperature and global ice volume over the past 420 ka, Quaternary Science Reviews 20:583-589.

Petit, J.R., et al., 1999. Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica. Nature 399: 429-436.

Siegenthaler, U. Et al., 2005. Stable carbon cycle-climate relationship during the late Pleistocene. Science 310: 1313-1317.