The Paris Agreement aims to keep global mean temperatures to within 2o C Celsius of pre-industrial levels, with an aspirational aim of remaining within 1.5o C. To achieve this, global carbon emissions (principally CO2) have to at least halve every decade over the next century. In line with the agreement, Scotland has committed to achieving net-zero emissions by 2045. We therefore require accurate and frequently updated knowledge of human-driven emissions. Robust monitoring is essential if we are to verify progress.

At present, greenhouse gas (GHG) emissions for Scotland are published annually, approximately 18 months after the period to which they relate. The current approach combines annual production and usage statistics with estimates of how much carbon is emitted per unit measure of production and usage. An alternative approach is to look to the atmosphere. This study examines how satellite observations of the atmosphere could be used to build on existing modelling efforts and report GHG emissions well in advance of the present estimates.

In this report, we describe the software we have developed to download and interpret publicly available satellite observations of tropospheric NO2, as a proxy for fossil fuel emissions of CO2 (ffCO2). The observations cover three spatial areas: onshore Scotland; the Scottish zone of the UK continental shelf; and the subset of the Scottish zone corresponding to the location of oil and gas platforms.

We used data from two satellite instruments: the Ozone Monitoring Instrument (OMI) and the TROPOspheric Monitoring Instrument (TROPOMI).

In the longer-term, the data collected can be used to improve emission estimates of ffCO2 over Scotland in the context of its commitment to achieving net-zero emissions by 2045.