PhD studentship in atmospheric science
Understanding the global sources and sinks of atmospheric carbonyl sulfide (OCS) in order to provide insights into carbon cycle processes
One of the principal driving factors of climate change is the anthropogenic perturbation to the carbon cycle, caused by such activities as the burning of fossil fuels and deforestation. Therefore, a better understanding of the carbon cycle is currently a pressing scientific issue.
The CO2 taken up by leaves during photosynthesis can be directly measured on the leaf scale. However on the global scale, i.e. on the scale of atmospheric measurements, it is impossible to distinguish it from the CO2 released by respiration, for example from non-photosynthetic parts of plants and soil microorganisms. This severely limits our understanding of CO2 sinks and sources on land.
The sulfur-containing analogue of CO2, carbonyl sulfide (OCS), has recently emerged as a proxy for the photosynthetic uptake of CO2 because it is not emitted during respiration. However, the atmospheric sources and sinks of OCS are poorly quantified. Monitoring atmospheric OCS concentrations via satellite remote sensing is particularly powerful because it provides global coverage, unlike ground-based measurements, and a high density of data.
The general aims of this project are to:
1. extract OCS global distributions from atmospheric spectra recorded by the Infrared Atmospheric Sounding Interferometer (IASI) satellite instruments onboard MetOp-A and MetOp-B.
2. model OCS global distributions using the TOMCAT 3D chemical transport model; this part of the project is carried out in collaboration with Prof Martyn Chipperfield, based in the School of Earth and Environment, University of Leeds, and is supported by a CASE award from the National Centre for Earth Observation.
3. interpret OCS observations/model outputs to understand OCS sources and sinks, and provide insights into carbon cycle processes.
Campbell, J. E., et al., Photosynthetic control of atmospheric carbonyl sulfide during the growing season, Science, 322, 1085-1088, 10.1126/science.1164015, 2008.
Asaf, D., et al., Ecosystem photosynthesis inferred from measurements of carbonyl sulphide flux, Nature Geoscience, 6, 186-190, doi:10.1038/ngeo1730, 2013.
Illingworth, S. M., et al., ULIRS, an optimal estimation retrieval scheme for carbon monoxide using IASI spectral radiances: sensitivity analysis, error budget and simulations, Atmos. Meas. Tech., 4, 269-288, doi:10.5194/amt-4-269-2011, 2011.
This studentship is funded by the Leicester Institute for Space and Earth Observation (LISEO), and the student will be affiliated with the National Centre for Earth Observation (NCEO). The NCEO (www.nceo.ac.uk) is a distributed NERC centre providing the UK with national capability in EO science.
The supervisory team comprises three scientists.
Dr Jeremy Harrison is the NCEO's spectroscopy leader and capability leader in atmospheric radiative transfer. Based in the Earth Observation Science (EOS) group, his expertise lies in atmospheric spectroscopy and the remote sensing of trace gases.
Prof Martyn Chipperfield is the NCEO's capability leader for atmosphere-land surface data assimilation. His expertise is in chemistry-transport modelling and the interpretation of satellite observations of atmospheric chemistry.
Prof John Remedios is the Director of the NCEO, and an expert in the remote sensing of trace gases.
Interested applicants are invited to contact Dr Jeremy Harrison (firstname.lastname@example.org).
This job comes from a partnership with Science Magazine and