Atmospheric nuclear weapons testing (NWT) resulted in the injection of plutonium (Pu) into the atmosphere and subsequent global deposition. We present a new method for continuous semiquantitative measurement of ²³⁹Pu in ice cores, which was used to develop annual records of fallout from NWT in ten ice cores from Greenland and Antarctica. The ²³⁹Pu was measured directly using an inductively coupled plasma–sector field mass spectrometer, thereby reducing analysis time and increasing depth-resolution with respect to previous methods. To validate this method, we compared our one year averaged results to published ²³⁹Pu records and other records of NWT. The ²³⁹Pu profiles from the Arctic ice cores reflected global trends in NWT and were in agreement with discrete Pu profiles from lower latitude ice cores. The ²³⁹Pu measurements in the Antarctic ice cores tracked low latitude NWT, consistent with previously published discrete records from Antarctica. Advantages of the continuous ²³⁹Pu measurement method are (1) reduced sample preparation and analysis time; (2) no requirement for additional ice samples for NWT fallout determinations; (3) measurements are exactly coregistered with all other chemical, elemental, isotopic, and gas measurements from the continuous analytical system; and (4) the long half-life means the ²³⁹Pu record is stable through time.

Item Type:	Refereed Article
Keywords:	239Pu, ice cores, Arctic, Antarctic, plutonium
Research Division:	Earth Sciences
Research Group:	Geochemistry
Research Field:	Isotope geochemistry
Objective Division:	Expanding Knowledge
Objective Group:	Expanding knowledge
Objective Field:	Expanding knowledge in the environmental sciences
UTAS Author:	Curran, M (Dr Mark Curran)
ID Code:	114873
Year Published:	2016
Web of Science® Times Cited:	25
Deposited By:	CRC-Antarctic Climate & Ecosystems
Deposited On:	2017-03-01
Last Modified:	2017-11-03
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