Scottish Air Quality Advisory Group advice note 2, March 2026

Where are the key opportunities for maximising co-benefits for both air pollutant and greenhouse gas reductions?

Electrification of the vehicle fleet using renewable and low-carbon electricity will likely maximise co-benefits in populated areas particularly. Encouragement to increase active travel in place of motor vehicle journeys will also result in co-benefits.

A substantial switch to the use of (green) hydrogen and ammonia as fuels is likely to deliver the largest co-benefits at the national level in terms of both greenhouse gas and air pollutant reductions (with the exception of ammonia). The unwanted effect of additional ammonia emissions on sensitive habitats and designated sites needs to be evaluated.

Reducing the amount of meat and dairy products in the diet has major potential to decrease ammonia and GHG emissions from agricultural practices (alongside practical and technological interventions on farming practices) which could reduce climate impacts (due to GHG reduction), environmental impacts (due to ammonia reductions) and benefit human health by reducing the formation of secondary particulate matter. There may also be benefits in terms of optimising the production and transport of food from farms and productivity increases due to reduced congestion.

Strategies which tackle 'super-pollutants' such as black carbon (often associated with combustion) and ozone (note, though, there tends to be an inverse relationship with NO₂, in high NOx emission source regions such as cities, another gas recognised to have adverse effects on human health) will be expected to have benefits for both climate change and air pollution.