Current Science

The long-term research goal of the group is to understand which processes are responsible for observed variations of Earth’s atmospheric chemical composition. The chemical composition of the atmosphere directly impacts Earth’s radiative balance and consequently surface warming. It also defines the oxidation capacity of the global troposphere that determines the quality of air where we live and breathe.

Turns out that methods we have developed to study Earth's atmosphere are also really useful to understand other planetary atmospheres. 

Planet Earth - CO2, methane, and atmospheric chemistry

Computational projects

We approach this goal mainly by developing novel mathematical models to reconcile new satellite observations with current knowledge. Often these models are too complex to resolve analytically so we tend to use computational approaches. These are a sample of some very broad computational research questions that are currently keeping us busy:

• Which natural and human-driven processes are responsible for observed variations in atmospheric CO2 and methane?

• How will they respond to changes in climate?

• How can we infer combustion emissions of CO2 from atmospheric measurements of CO2?

• Which processes are driving observed changes in tropospheric chemistry and how do they affect surface air quality?

• What is the relative importance of anthropogenic, biogenic, and pyrogenic emissions?

Field campaigns and instrument development

Over the last decade or so we have also led the development of field experiments using research aircraft and ground-based instruments and have designed science requirements for new aircraft and satellite instruments. Here are our current projects:

• NEW CurFEW (Current and Future Emissions of African Wetland Methane) is a new NERC-funded large grant that starts in October 2025 and last for five years. The aim of CurFEW is to improve predictions of tropical wetland emissions and associated feedbacks in a rapidly changing climate. We are going to achieve this by developing and embedding new emission process knowledge, informed by field and laboratory data and by satellite data, into submodels that define the UK Earth System model (UKESM). This is a project is co-led with the UK Centre for Ecology and Hydrology and a team from the Met Office, the Universities of Aberystwyth and Exeter in the UK, and Universities of Botswana, Rwanda, Makerere, Jose Eduardo dos Santos University, and Game Rangers International. More details to follow. 

• GEMINI-UK (Greenhouse gas Emissions Monitoring network to Inform Net-zero Initiatives for the UK).

With the University of Leicester, we are leading the development and exploitation of a nationwide network of ground based FTIR spectrometers (Bruker EM27/SUNs). Collectively, these instruments will help estimate regional net flux estimates of CO2 and methane, as part of a broader Measurement Reporting Verification system to support the Paris Agreement commitments.

• GEMINI+Edinburgh (Greenhouse gas Emissions Monitoring network to Inform Net-zero Initiatives plus air quality measurements across the City of Edinburgh).

We are installing a city-wide network of EM27/SUNs to construct a dome across Edinburgh so we can track changes in net emissions of CO2 and methane. We are also installing a range of sensors to map air pollution across the City of Edinburgh in near-real time.

• NIMCAM (Near Infrared Multispectral Camera for Atmospheric Methane).

This is a satellite mission concept that is being developed within the group.  It has been designed to collected atmospheric methane data at a resolution of tens of metres with a sensitivity that is suitable for quantifying 95% of leaks across Europe. Currently, NIMCAM is at the field demonstrator stage.

• MicroCarb (Launch date in July 2025)

MicroCarb is the first European mission intended to characterise greenhouse gas fluxes on Earth’s surface and gauge how much carbon is being absorbed by oceans and forests, the main sinks on the planet. We are the UK science lead on this French-UK MicroCarb mission. 

Mars

We are developing an established 3-D Mars Global Circulation Model to interpret data collected by the NOMAD and ACS instruments aboard the ExoMars Trace Gas Orbiter (TGO). We are refining the network of chemical reactions, including organic chemistry and chlorine chemistry. This builds on work we have done with a 1-D model (Taysum and Palmer, 2020). We have a wide range of science questions but here are our two broad research questions:

• How rich is the atmospheric chemistry that is theoretically supported in the Martian atmospheric environment? How does it change on a seasonal basis?

• How can 3-D models help inform the development of exploratory retrievals of chemical compounds? [This will help us to better understand what is achievable with the observed spectra]

To address these questions, we are working closely with the Mars modelling community and the TGO retrieval teams.

Exoplanets

Through various collaborations we are studying the atmospheric chemical composition of Mars and exoplanets, and to interpret observed variations of brown dwarf light curves in terms of atmospheric features. Using models and data we are beginning to address some broad fundamental questions:

• What kind of atmospheric chemistry is sustainable within exoplanetary atmospheres?

How can we harness JWST data to confront our current understanding?

• What dynamical regimes are supported by tidally locked exoplanets and how do they differ from Earth?

• Can an exoplanet analogue for early-Earth support the development of pre-biotic molecules?

• How can we effectively harness machine learning methods to expedite JWST data processing?

• What can we learn about the atmospheric chemistry on Mars from new satellite observations?

Can wider atmospheric chemistry be the key to explaining observations of Martian methane?