Atmospheric scientist at the University of Bristol
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 Continue reading An alternative explanation for recent methane increases
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 Continue reading BBC Radio 4 Counting Carbon
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 – Continue reading Measuring greenhouse gases during India’s monsoon
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 Continue reading Comment for BBC report on nitrous oxide from agriculture
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 Continue reading Resolving discrepancies in reported HFC 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 Continue reading Estimating the UK’s greenhouse gas 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 Continue reading Quantifying aluminum and semiconductor PFC emissions
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 Continue reading Hierarchical Bayesian inversions
Inverse modeling for atmospheric trace gas inversions describes the statistical estimation of emissions given a set of atmospheric concentration data. By measuring the composition over time and knowing how material is transported through the atmosphere, we can estimate the emissions Continue reading Inverse modeling 101
One of my main research interests is in measuring the concentrations of greenhouse gases in South Asia, an area that holds significant implications for global climate and climate policies. Despite its importance, this region of the world is poorly monitored Continue reading In situ greenhouse gas measurements in India