Novel Methods for Atmospheric Carbon Dioxide Retrieval from the JAXA GOSAT and NASA OCO-2 Satellites

Since the beginning of the industrial age, the concentration of carbon dioxide (CO2) has increased from about 280 parts per million to over 390 parts per million to date. Furthermore, a global network of ground-based measurement sites has observed an increase in atmospheric CO2 concentration by almost 20% over the past 50 years - the most dramatic change that we have ever seen in human history. The nature and the geographic distribution of the sinks that absorb about half of the human generated CO2 are currently not well known and present important, yet unanswered questions. For example, if the efficiency of these sinks decreases in the future, will the rate of build-up of atmospheric CO2 increase? If so, how much? Can some of these natural sinks be exploited to further reduce the rate of CO2 build-up? An improved understanding of nature, location, and processes governing the efficiency of these natural sinks is therefore essential to predict the rate of build-up of CO2 in the atmosphere, and its impact on our climate.

Measurements from satellites of the atmospheric CO2 can lead to a major revolution in our understanding of the carbon cycle due to their global and dense observations. The first dedicated greenhouse gas satellite GOSAT has been in launched in 2009 by JAXA/NIES and NASA will launch their OCO-2 mission in summer 2014 and the field of greenhouse gas remote sensing has developed into a key area of Earth Observation (e.g. as part of the ESA Climate Change Initiative). One of the big challenges is to develop the best-possible methods for inferring atmospheric CO2 from such satellite measurements and our group at University of Leicester is one of the main groups worldwide in this area. The key towards for the retrieval method is the description of the physics of the transfer of light through the atmosphere and surface and in this studentship will develop improved but fast methods and apply this method to observations of the new NASA OCO-2 mission. The observations from OCO-2 will provide an unprecedented view on the atmospheric distribution of CO2 which can be a breakthrough in understanding where carbon is exchanged between the atmosphere and terrestrial ecosystems.

The overarching goal of this project is study the global carbon cycle with space-based observations from GOSAT and the new NASA OCO-2 satellite mission. Specifically, the student will 1) investigate methods for improving the treatment of plant fluorescence and desert dust aerosols and for accelerating the retrieval method; both have been identified as insufficient from our analysis of GOSAT data; 2) adapt the retrieval method to the new NASA OCO-2 satellite and 3) use OCO-2 datasets to test our understanding of the carbon cycle for key regions such as Tropics and boreal regions (in collaboration with model groups from University of Edinburgh and Leeds).


We are an equal opportunities employer and particularly welcome applications for Ph.D. places from women, minority ethnic and other under-represented groups.