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Samples originating from the time period after 1950 can be radiocarbon dated utilising the 14C bomb peak as a calibration curve. The applicability of “radiocarbon dating” of recent organic human material for the determination of the time of death of humans was tested. The radiocarbon results from hair and lipid samples from individuals with known date of death were compared with the results from two individuals with unknown time of death. An estimate of the year of death for the unknowns could be derived by this way. Due to the long turnover time of collagen in human bones it is not possible to use the radiocarbon content of bone collagen for a reliable estimate. In order to study the time dependence of the collagen turnover we tested “soft” chemical methods for the isolation of collagen from the bone matrix. First radiocarbon results of this investigation are presented.

In addition to 14C, a large set of δ13C data was produced at NOSAMS as part of the World ocean circulation experiment (WOCE). In this paper, a subset of 973 δ13C results from 63 stations in the Pacific Ocean was compared to a total number of 219 corresponding results from 12 stations sampled during oceanographic programs in the early 1970s. The data were analyzed in light of recent work to estimate the uptake of CO2 derived from fossil fuel and biomass burning in the oceans by quantifying the δ13C Suess effect in the oceans. In principle, the δ13C value of dissolved inorganic carbon (DIC) allows a quantitative estimate of how much of the anthropogenic CO2 released into the atmosphere is taken up by the oceans, because the δ13C of CO2 derived from organic matter (∼−27‰) is significantly different from that of the atmosphere (∼−8‰). Our new analysis indicates an apparent discrepancy between the old and the new data sets, possibly caused by a constant offset in δ13C values in a subset of the data. A similar offset was reported in an earlier work by Paul Quay et al. for one station that was not included in their final analysis. We present an estimate for this assumed offset based on data from water depths below which little or no change in δ13C over time would be expected. Such a correction leads to a significantly reduced estimate of the CO2 uptake, possibly as low as one half of the amount of 2.1 GtC yr−1 (gigatons carbon per year) estimated previously. The present conclusion is based on a comparison with a relatively small data set from the 70s in the Pacific Ocean. The larger data set collected during the GEOSECS program was not used because of problems reported with the data. This work suggests there may also be problems in comparing non-GEOSECS data from the 1970s to the current data. The calculation of significantly lower uptake estimates based on an offset-related problem appears valid, but the exact figures are tentative because the data set is small and the cause for an offset remains unknown. Therefore, it would be desirable to extend this comparison to the Indian Ocean where it is believed that better GEOSECS δ13C data are available.

The huge amount of raw data collected during routine 14 C AMS measurements requires sophisticated processing tools to guarantee the quality and reliability of the resulting radiocarbon dates. This paper discusses the automatic evaluation system, that is in use and under continuous development at the Vienna Environmental Research Accelerator (VERA) laboratory. It includes a calibration program which is able to handle the bomb-peak. The flexibility of the system allows its use for other rare isotopes also.

This paper presents a brief recollection of the discovery of the Iceman “Otzi”, an extraordinary archaeological find which opened up a window to prehistoric life some 5000 years ago. A selected number of investigations are also presented, with particular emphasis on the 14C dating method.

The possibilities of computer-assisted and automated accelerator mass spectrometry (AMS) measurements were explored. The goal of these efforts is to develop fully automated procedures for “routine” measurements at the Vienna Environmental Research Accelerator (VERA), a dedicated 3-MV Pelletron tandem AMS facility. As a new tool for automatic tuning of the ion optics we developed a multi-dimensional optimization algorithm robust to noise, which was applied for 14C and 10Be. The actual isotope ratio measurements are performed in a fully automated fashion and do not require the presence of an operator. Incoming data are evaluated online and the results can be accessed via Internet. The system was used for 14C, 10Be, 26Al and 129I measurements.

VERA is a new 3-MV Pelletron tandem AMS facility in Vienna, which was installed during the last months of 1995. This report will discuss the performance characteristics of the facility established during the test operating phase and present first measurements of 14C standards.