Nicholas Shackleton

From Wikipedia, the free encyclopedia

"Nick" Shackleton

Sir Nicholas John Shackleton FRS (23 June 1937—24 January 2006) was a British geologist and climatologist who specialised in the Quaternary Period. He was the great-nephew of the explorer Ernest Shackleton and the son of the noted geologist Robert Millner Shackleton.

He earned a bachelor's degree in physics and a Ph.D. in geochemistry from Clare College, University of Cambridge. He spent his entire career there, eventually becoming a Professor in the Department of Earth Sciences, working in the Godwin Institute for Quaternary Research.

The Glacial effect describes the change of the oxygen isotope composition of sea water, due to growing ice sheets in high latitudes during glacials.

Shackleton was a key figure in the field of palaeoceanography, and was a pioneer in the use of mass spectrometry to determine changes in climate as recorded in the oxygen isotope composition of calcareous microfossils. He also found evidence that the earth's last magnetic field reversal was 780,000 years ago. He is probably best known for his contribution to the "Hays, Imbrie and Shackleton" paper in Science in 1976 which, using ocean sediment cores, demonstrated that oscillations in climate over the past few million years could be correlated with variations in the orbital and positional relationship between the Earth and the Sun (see Milankovitch cycles).

Much of Shackleton's later work focused on constructing precise timescales based on matching the periodic cycles in deep-sea sediment cores to calculations of incoming sunlight at particular latitudes over geological time, a method which allows a far greater level of stratigraphic precision than other dating methods, and also helped to clarify the rates and mechanisms of aspects of climate change.

In September 2000 he published an innovative study of the relationship between the oxygen isotope record of the oceans and isotope records obtained from the ice in Antarctica (glacial effect). This helped to pin down the relative contribution of deep water temperature changes and ice volume changes to the marine isotopic record, and also highlighted the close interdependency between carbon dioxide levels and temperature change over the last 400,000 years.

In 1995 became the director of the Godwin Institute of Quaternary Research. In 1998, he was knighted for his contributions to science. From 1999 to 2003 he was president of the International Union for Quaternary Research (INQUA). He also had a fine collection of early clarinets and other woodwind instruments, which he played and studied.