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ENV East Doctoral Training Partnership


Applications to the EnvEast Doctoral Training Partnership are now closed.

Below you can browse some of the PhD projects we have previously funded; if you would like to be informed when applications open, or if you have any questions about EnvEast and our application process, please email us.

Projects previously funded by EnvEast


New threats to the ozone layer: Exploring ozone-depleting substances in the upper troposphere and stratosphere

Project description

The stratosphere contains ≈20 % of the mass of the atmosphere and extends from about 10 to 50 km. It is home to the ozone layer, which also protects life from harmful UV radiation. The large-scale depletion of this layer is a man-made problem that has persisted for decades. It is however not only an ongoing problem, but of renewed concern. 

Previously undetected ozone-depleting substances (ODSs) have been found to be present in the atmosphere, and some of these are increasing in concentration (Laube et al., Nature GeoScience, 2014). Moreover, some other ODSs that are not controlled by international treaties are also increasing in concentration. Of particular interest here are the rapidly developing economies of many countries in South and East Asia (Leedham Elvidge et al., ACP, 2015). Another major concern is changes to transport patterns within the stratosphere, which are hard to track. The recently discovered isotopic ‘fingerprints’ of ODSs in the stratosphere (Laube et al., Science, 2010) could provide new insights to such transport changes.

This studentship will investigate ODSs and their isotopes in the stratosphere through unique data and air samples from a variety of sources, including two upcoming high-altitude aircraft campaigns above northern Sweden and India. The student will work with the most sensitive gas chromatography-mass spectrometry (GC-MS) system for atmospheric trace gases in Europe and, in addition, with a new, next generation Time-of-flight GC-MS system which is ideal for finding new ODSs. These will be exciting new avenues to explore the stratosphere and improve the understanding of ODSs and their past and future impact on the ozone layer.

The student will be trained in these techniques and will also acquire skills in handling the latest instrument and retrieval software as well as a detailed understanding of the analytical and atmospheric background. This project is very international through a variety of collaborators and the student will be networking with those partners as well as attending national and international conferences.


Laube, J., Kaiser, J., Sturges, W., Bonisch, H., Engel, A. (2010) Chlorine isotope fractionation in the stratosphere in : Science 329. pp. 1167

Laube, J. C., Newland, M. J., Hogan, C., Brenninkmeijer, C. A. M., Fraser, P. J., Martinerie, P., Oram, D. E., Reeves, C. E., Röckmann, T., Schwander, J., Witrant, E., Sturges, W. T. (2014) Newly detected ozone-depleting substances in the atmosphere in Nature Geoscience 7. pp. 266-269

Leedham Elvidge, E. C., Oram, D. E., Laube, J. C., Baker, A., Montzka, S. A., Humphrey,S., O'Sullivan, D. A., Brenninkmeijer, C. A. M. (2015) Increasing concentrations of dichloromethane, CH2Cl2 in Atmospheric Chemistry and Physics 15. pp. 1939-1958

Mahieu, E., et al. (2014) Recent Northern Hemisphere stratospheric HCl increase due to atmospheric circulation changes in Nature 515. pp. 104–107

  • Start date September 2016