aganesan

PhD positions available for NERC GW4+ competition

See Vacancies for more information and get in touch if interested. Please visit the NERC GW4+ website for eligibility criteria regarding residency and other requirements.

Stable methane emissions from India

Our study has found that India’s methane emissions have been stable and were not rising between 2010 and 2015. This is in contrast to other countries such as China, where emissions have risen due to increased fossil fuel emissions, or the United States, where emissions may in fact be falling. …

An alternative explanation for recent methane increases

Our new study, led by Matt Rigby, which has been published in the Proceedings of the National Academy of Sciences, demonstrates the role of methane oxidation by the hydroxyl radical to explain the post 2007 growth in atmospheric methane concentrations. Several recent studies have proposed a variety of mechanisms that could explain …

BBC Radio 4 Counting Carbon

Listen to the BBC Radio 4 documentary Counting Carbon. In it, I am speaking along with other scientists about the problems associated with greenhouse gas reporting and the implications of this on climate agreements. A write-up of the story is featured on the BBC.

Measuring greenhouse gases during India’s monsoon

This past summer, researchers across the UK and India are teaming up to study the Indian monsoon as part of a £8 million observational campaign using the NERC research aircraft BAe-146. India receives 80% of its annual rainfall in three months – between June and September. There are large year-to-year differences in …

Comment for BBC report on nitrous oxide from agriculture

I was asked to comment on a BBC article reporting on a study published in PNAS, which has found that nitrous oxide emissions from streams (where nitrogen added to the soil can often end up), is much larger than previously thought. The authors have speculated that this source could be underestimated by as …

Resolving discrepancies in reported HFC emissions

In a new study published in the Proceedings of the National Academy of Sciences, we investigated the sources of discrepancy between HFC emissions reported to the UNFCCC and “top-down” emissions inferred from atmospheric observations. We found that the majority of the gap can be attributed to non-reporting or developing nations. …

Estimating the UK’s greenhouse gas emissions

In parallel with efforts to create a detailed bottom-up inventory (National Atmospheric Emissions Inventory) for the major greenhouse gases, the UK has funded four monitoring stations to infer emissions for the purposes of verification. In our new study, available on Atmospheric Chemistry and Physics Discussions, we have used two years …

Quantifying aluminum and semiconductor PFC emissions

Colleagues at the Scripps Institution of Oceanography (lead author: Dr Jooil Kim) and institutes around the world have recently published work detailing the breakdown of perfluorocarbon (PFC) emissions from the aluminum and semiconductor industries. While we found in earlier work that reports to the United Framework Convention on Climate Change only …

Hierarchical Bayesian inversions

One of the main issues in trace gas inversions is in being able to correctly quantify the uncertainties in the system, as the inversion is very sensitive to these parameters. These errors include a complete understanding of uncertainties in the instrument, uncertainties in the model and uncertainties in the a …