Scope3 has opened up its ad emissions database as it bids to set the standard for measuring the carbon impact of ads end-to-end.

The move comes as advertisers grapple with how to reduce the emissions from advertising, which Scope3 said runs to “millions of metric tonnes” from digital ads alone.

The first step, per the firm, is standardised and reliable measurement. Opening up its database means that “there’s no excuse for inaction”, said Scope3 COO and Co-Founder, Anne Coghlan.

The company claims its platform means advertisers can gauge carbon emissions by platform and publisher across web, apps and connected TV as well as the digital supply chain. Shortening that supply chain, founder Brian O’Kelley has previously told Mi3, is the fastest way to cut carbon, and most likely budget wastage.

He suggested brands can halve their carbon footprint within 12 months if they stop buying “crap” ads that “no human sees”, ditch “gamed” viewability metrics and instead buy on attention, while never buy another outstream video ad.

Via the platform brands can also access rankings across media and track their carbon emission changes over time.