GEMINI-UK: Towards improved carbon flux estimates for the UK using a national network of ground-based greenhouse gas observing spectrometers

The UK has a long-term goal in place to achieve net-zero greenhouse gas (GHG) emissions by 2050. As part of the UK Greenhouse gas Emissions Measurement Modelling Advancement programme (GEMMA), which aims to provide regular, timely, data-driven emissions estimates for the UK at a regional scale, scientists from the National Centre for Earth Observation have set up a network of ground-based shortwave infrared spectrometers around the UK. This network, called GEMINI-UK (Greenhouse gas Emissions Monitoring network to Inform Net-zero Initiatives for the UK), will provide continuous observations of the column concentrations of carbon dioxide and methane during cloud-free conditions from locations around the country.

Through the GEMMA programme data from GEMINI-UK will be used in a Bayesian inversion framework, along with other sources of GHG concentration data in the UK, to constrain regional flux estimates of carbon dioxide and methane. We have designed GEMINI-UK to deliver the biggest uncertainty reductions in carbon dioxide flux estimates, working closely with host partners that include UK universities, a research institute and a secondary school to promote the open access and transparency of the collected data. The network comprises ten new Bruker EM27/SUN spectrometers, which we operate in automated weatherproof enclosures using a design developed by University of Edinburgh researchers, allowing year-round autonomous observations across multiple sites.

In this presentation we describe the status, network design, first data, and longer-term goals of GEMINI-UK, including an ongoing evaluation of the GEMINI-UK station located alongside the high resolution TCCON (Total Carbon Column Observing Network) spectrometer at the Rutherford Appleton Laboratory in Harwell, Oxfordshire. In addition, we show the potential for GEMINI-UK data to constrain carbon dioxide and methane fluxes for the UK using a regional Bayesian inversion framework, and demonstrate the opportunities that GEMINI-UK provides for regional scale validation of existing and future greenhouse gas observing satellite missions.