Laboratory of Environmental Chemistry
The surface chemistry research group investigates multi-phase chemical processes relevant for atmospheric chemistry and the analytical chemistry research group reconstructs environmental and climatic conditions from high-altitude glaciers.
The Latest News
Congratulations to Sven Avak
On 31 January 2019 Sven successfully defended his PhD entitled “Impact and Implications of Melting on the Preservation of Trace Elements in High-Alpine Snow and Glacier Ice" at the University of Bern. Congratulations! This thesis formed part of the collaborative project Microscale Distribution of Impurities in Snow and Glacier Ice (MiSo) in co-operation with LUC's Surface Chemistry research group and the WSL-SLF Davos. The project was funded by the Swiss National Science Foundation.
Congratulations to Dimitri Osmont
Dimitri successfully defended his PhD at the University of Bern, entitled "Reconstruction of forest fires through chemical analysis of black carbon in ice cores from high- alpine glaciers". This thesis formed part the collaborative project paleo fires with ETH Zürich and University of Bern funded by the Swiss National Science Foundation.
Current Scientific Highlight
Why the Little Ice Age ended in the middle of the 19th century
In the first half of the 19th century, a series of large volcanic eruptions in the tropics led to a temporary global cooling of Earth's climate. That Alpine glaciers grew and subsequently receded again during the final phase of the so-called Little Ice Age was due to a natural process. This has now been proven by PSI researchers on the basis of ice cores.
Light from the particle accelerator helps to understand ozone decomposition
PSI researchers have developed an experimental chamber in which they can recreate atmospheric processes and probe them with unprecedented precision, using X-ray light from the Swiss Light Source SLS. In the initial experiments, they have studied the production of bromine, which plays an essential role in the decomposition of ozone in the lower layers of the atmosphere. In the future, the new experiment chamber will also be available for use by researchers from other scientific fields.
Coexistence of Physisorbed and Solvated HCl at Warm Ice Surfaces
The interfacial ionization of strong acids is an essential factor of multiphase and heterogeneous chemistry in environmental science, cryospheric science, catalysis research and material science. Using Near Ambient Pressure X-ray Photoelectron (NAPP) spectroscopy, we directly detected a low surface coverage of adsorbed HCl at 253 K in both molecular and dissociated states and interpret the results as physisorbed molecular HCl at the outermost ice surface and dissociation occurring upon solvation deeper in the interfacial region. This study gives clear evidence for nonuniformity across the air−ice interface and questions the use of acid−base concepts in interfacial processes.
The Latest Publications
A Holocene black carbon ice-core record of biomass burning in the Amazon Basin from Illimani, Bolivia
Climate of the Past 15, 579-592 (2019).DOI: 10.5194/cp-15-579-2019
A new method for the determination of primary and secondary terrestrial and marine biomarkers in ice cores using liquid chromatography high-resolution mass spectrometry
Talanta 194, 233-242 (2019).DOI: 10.1016/j.talanta.2018.10.042