Alexander Zapf
Oeschger Centre for Climate Change Research
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Publication
Featured researches published by Alexander Zapf.
Radiocarbon | 2013
Fang Cao; Yanlin Zhang; Soenke Szidat; Alexander Zapf; Lukas Wacker; Margit Schwikowski
Carbonaceous particles that comprise organic carbon (OC) and elemental carbon (EC) are of increasing interest in climate research because of their influence on the radiation balance of the Earth. The radiocarbon determination of particulate OC and EC extracted from ice cores provides a powerful tool to reconstruct the long-term natural and anthropogenic emissions of carbonaceous particles. However, this 14C-based source apportionment method has not been applied for the firn section, which is the uppermost part of Alpine glaciers with a typical thickness of up to 50 m. In contrast to glacier ice, firn samples are more easily contaminated through drilling and handling operations. In this study, an alternative decontamination method for firn samples consisting of chiselling off the outer parts instead of rinsing them was developed and verified. The obtained procedural blank of 2.8 ± 0.8 μg C for OC is a factor of 2 higher compared to the rinsing method used for ice, but still relatively low compared to the typical OC concentration in firn samples from Alpine glaciers. The EC blank of 0.3 ± 0.1 μg C is similar for both methods. For separation of OC and EC for subsequent 14C analysis, a thermal-optical method instead of the purely thermal method was applied for the first time to firn and ice samples, resulting in a reduced uncertainty of both the mass and 14C determination. OC and EC concentrations as well as their corresponding fraction of modern for firn and ice samples from Fiescherhorn and Jungfraujoch agree well with published results, validating the new method.
Quaternary Science Reviews | 2013
Pierre-Alain Herren; Anja Eichler; Horst Machguth; Tatyana Papina; Leonhard Tobler; Alexander Zapf; Margit Schwikowski
Journal of Glaciology | 2012
I. G. M. Wientjes; R. S. W. van de Wal; Margit Schwikowski; Alexander Zapf; Simon Fahrni; Lukas Wacker
Journal of Glaciology | 2016
Elena M. Aizen; Vladimir B. Aizen; Nozomu Takeuchi; Paul Andrew Mayewski; B. Grigholm; Daniel R. Joswiak; Stanislav A. Nikitin; Koji Fujita; Masayoshi Nakawo; Alexander Zapf; Margit Schwikowski
The Cryosphere | 2016
Chiara Uglietti; Alexander Zapf; Theo M. Jenk; Michael Sigl; Sönke Szidat; Gary Salazar; Margit Schwikowski
Radiocarbon | 2013
Alexander Zapf; Atle Nesje; Sönke Szidat; Lukas Wacker; Margit Schwikowski
The Cryosphere Discussions | 2016
Chiara Uglietti; Alexander Zapf; Theo M. Jenk; Sönke Szidat; Gary Salazar; Margit Schwikowski
Archive | 2015
Chiara Uglietti; Alexander Zapf; Sönke Szidat; Gary Abdiel Salazar Quintero; Douglas R. Hardy; Margit Schwikowski
Archive | 2012
Fang Cao; Yanlin Zhang; Alexander Zapf; Sönke Szidat; Lukas Wacker; Margit Schwikowski
Archive | 2012
Alexander Zapf; Atle Nesje; Sönke Szidat; Lukas Wacker; Margit Schwikowski