Ice Cores - Society for Interdisciplinary Studies

Some interesting ideas on the ice cores. Are the mainstream dates acceptable because they fit into the uniformitarian model as they appear to rely on oxygen isotopes for dating the cores. An alternative method of dating the cores may have been rejected because the dates did not match the theory. This fascinating debate can be found at

The rejected alternative, microparticle concentration variations rather than oxygen isotopes (loved by uniformitarians) can be viewed at www.igsoc.org:8080/journal/14/72/igs_journal_vol14_issue072_pg433-444.pdf … and the lead author turned out to be Lonnie Thompson who went on to study various mountain glaciers around the world and came up with the idea they were melting as a result of global warming. In the 1970s to 1980s the worry was global cooling and the onset of a new Ice Age. Funny how these things change with different personalities and different fashions.

The interesting thing that caught my eye in the Thompson et al paper is that if bedrock was reached at 27,000 years ago and then this is not much out from the beginning of the Late Glacial Maximum. Not exactly – but not too far away. The microparticle chronology was attacked on the basis that it was deemed more unreliable than oxygen isotopes. The ice core research appeared to be backed up by sediment cores from the N Atlantic – which are also based on oxygen isotopes in the shells of foraminifera plankton. Indeed, the whole basis of 100,000 year cycles for the Ice Ages revolves around these oxygen isotopes. They are of course supplemented by very minor changes in orbit – the 100,000 year Milankovitch cycle, but basically the latter could not run without the oxygen isotopes. How reliable are they?

One outcome of the joining at the hip of ice cores, sediment cores and Milankovitch, was that interglacial periods were limited to relatively short periods of 10,000 years. Although this has been stretched in recent years as field evidence appears to contradict the idea all interglacials were short affairs, at the time it caused something of a stir. Some scientists, as seems to be their want, started warning the world that the present interglacial episode was about to reach its end. They even went so far as to browbeat Richard Nixon, the then president of the US (shows how long ago all this took place). Some things never change. Its not an Ice Age that we are being warned about nowadays but a supersonic heat wave that is going to fry everyone. Clearly, scientists of the time were completely convinced of the validity of oxygen isotopes to the same degree that scientists prone to over-hyping their profession are convinced of the idea that co2 is a greenhouse gas that threatens doom and destruction. That is cause to pause and ponder. What if?