Nicholas Shackleton

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Sir Nicholas John Shackleton (born June 23, 1937 in London , † January 24, 2006 in Cambridge ) was a British geologist and paleoclimatologist . He specialized in researching the most recent sediments on the ocean floor, which for him could provide information about the climate development from the beginning of the Ice Age in the Quaternary to the present day.

Life

Nicholas Shackleton, called "Nick", was born into an important family of British scientists. He was the great-nephew of the polar explorer Sir Ernest Shackleton and the son of the geologist Robert Millner Shackleton . He was given the opportunity to study at Clare College , Cambridge , where he graduated with a bachelor's degree in physics and then specialized in geochemistry for his dissertation . During this work he was in close contact with Cesare Emiliani , the founder of paleoceanography and isotope stratigraphy. Shackleton stayed in Cambridge after completing his doctorate in 1967 and eventually became Professor of Earth Sciences at Cambridge University .

Ice effect

Shackleton was a key figure in the field of paleoceanography and a pioneer in the field of the use of mass spectrometry to determine the 16 O / 18 O isotope ratio in calcite of fossil microorganisms ( foraminifera ). By determining and defining oxygen isotope levels , Shackleton was not only able to improve the age determination of marine sediments (isotope stratigraphy), but also to draw conclusions about the Earth's climate in the Quaternary . An important finding by Shackleton was that the isotopic composition of seawater is based on fractionation during evaporation. Due to the accumulation of the light isotope 16 O in the polar ice, the sea water becomes isotopically heavier in ice ages ( ice effect ). The isotope signal in the foraminifera thus reflects the global ice volume.

In 1976, his contribution to the scientific journal Science , in which he and his colleagues Imbrie and Hays showed that climate fluctuations over the past few million years correlate very precisely with changes in the earth's orbit around the sun and the position of the earth's axis ( Milanković Cycles ). This led to the fact that the theory of the Serbian mathematician Milutin Milanković , which had been discussed since 1929, was generally accepted, according to which the distribution of solar radiation on the earth's surface is one of the decisive factors for medium-term climate change. Shackleton later showed that these climatic variations were accompanied by changes in the carbon dioxide content of the atmosphere. Further work focused on creating precise scales for the geological periods of the Quaternary. Shackleton also found that the last reversal of the Earth's magnetic field must have occurred 780,000 years ago.

Shackleton had since 1985 a member of the Royal Society and was founded in 1998 for his services in the geosciences by the Queen to Knight Bachelor beaten ( "Sir"). Since 1995 he has been the director of the Godwin Institute for Quaternary Research . From 1999 to 2003 he was President of the International Union for Quaternary Research (INQUA). He was also known for his collection of old woodwind instruments, especially clarinets , which he could also play excellently.

Awards

Web links

Commons : Nicholas Shackleton  - collection of images, videos and audio files

Individual evidence

  1. ↑ JD Hays, J. Imbrie, NJ Shackleton: Variations in the Earth's Orbit: Pacemaker of the Ice Ages . In: Science . tape 194 , no. 4270 , December 10, 1976, p. 1121–1132 , doi : 10.1126 / science.194.4270.1121 .
personal data
SURNAME Shackleton, Nicholas
ALTERNATIVE NAMES Shackleton, Sir Nicholas John (full name)
BRIEF DESCRIPTION British geologist
DATE OF BIRTH June 23, 1937
PLACE OF BIRTH London
DATE OF DEATH January 24, 2006
Place of death Cambridge