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There is an interesting News Focus story in this week’s Science journal, that helps to confirm the different climate histrories for the East and West Antarctic ice sheets – a phenomenon that persists in modern times:

ANTARCTICA: Freeze-Dried Findings Support a Tale of Two Ancient Climates

A surprising cache of ancient plant material adds evidence for divergent climate histories of the East and West Antarctic ice sheets over the past 14 million years

Excerpt: These findings appear to be contradictory at first glance, but in fact they buttress an evolving view among scientists that the two major features of the continent, the western and eastern ice sheets, have experienced vastly different climate histories. Data from the Dry Valleys reveals an East Antarctic Ice Sheet that is high, dry, cold, and stable, at least in its central area. And the ANDRILL cores suggest a more volatile West Antarctic Ice Sheet that is subject to the changing temperatures of the sea in which it wades. “It reaffirms the fragility of the West Antarctic Ice Sheet [WAIS] and the stability of the central part of the East Antarctic Ice Sheet,” says Peter Barrett, a sedimentologist at the Victoria University of Wellington (VUW) in New Zealand, who advised the ANDRILL project.

I find this really amusing for a number of reasons. I refer to an article in this week’s Nature entitled ‘A large discontinuity in the mid-twentieth century in observed global-mean surface temperature’ by Thompson, Kennedy, Wallace and Phil Jones.

The abstract states:

“Data sets used to monitor the Earth’s climate indicate that the surface of the Earth warmed from approx 1910 to 1940, cooled slightly from approx 1940 to 1970, and then warmed markedly from approx 1970 onward. The weak cooling apparent in the middle part of the century has been interpreted in the context of a variety of physical factors, such as atmosphere–ocean interactions and anthropogenic emissions of sulphate aerosols. Here we call attention to a previously overlooked discontinuity in the record at 1945, which is a prominent feature of the cooling trend in the mid-twentieth century. The discontinuity is evident in published versions of the global-mean temperature time series, but stands out more clearly after the data are filtered for the effects of internal climate variability. We argue that the abrupt temperature drop of approx 0.3 °C in 1945 is the apparent result of uncorrected instrumental biases in the sea surface temperature record. Corrections for the discontinuity are expected to alter the character of mid-twentieth century temperature variability but not estimates of the century-long trend in global-mean temperatures.”

Amusement number one is the fact that AGW supporters have tried to explain the 1940s to 1970s ‘cooling’ using emissions of sulphate aerosols as an excuse – an explanation that I have previously challenged

Amusement number two is the unverifiable data used by Phil Jones et al 1990, which was relied upon by the IPCC to diminish the effect of urbanisation on the surface temperature record.

Amusement number three is that Steve McIntyre of Climate Audit first noted the discontinuity in the sea surface temperature record in June 2005.

Zip over to Climate Audit and read Nature “Discovers” Another Climate Audit Finding