Ad Net Zero updates sustainability guidelines to drive media decarbonisation

After launching its Global Media Sustainability Guidelines at last year’s Cannes Lions festival, Ad Net Zero has returned with the first big update to the framework.

Announced during the Cannes Lions at a panel (video below) featuring Mastercard, IAB Europe and Impact Plus, the updated framework completely operationalises the methodology for measuring greenhouse gas emissions across the three largest advertising channels: digital, TV, and OOH. Guidance for print, audio and cinema has also been developed and is set to roll out by the end of the year.

These updates address key challenges like data fragmentation and inconsistencies in emissions calculations, offering advertisers, agencies, and media owners a unified system for estimating and reporting emissions.

The GMSF was developed collaboratively with input from 53 marketers, all six holdcos, 31 media owners, and 27 industry associations across 42 markets.

Media emissions, which account for up to 55% of total emissions for marketing agency holding companies and up to 35% for some advertisers, represent a critical area of focus for sustainability efforts.

Mastercard’s ‘Priceless’ campaign featuring Lionel Messi was talked about as an example of how simple changes can drive effective carbon reductions without sacrificing commercial success. By compressing a video file from 125 megabytes to around two, the company reduced its carbon impact by 90%, according to Jay Altschuler, Mastercard’s SVP of global media and agency relations, who spoke on the panel.

“This is the big aha and insight,” Altschuler said. “You don’t have to compromise your ultimate business goals while at the same time reducing carbon. Both can play into each other,” he added, noting that digital and social video remain Mastercard’s most effective channels for ROI. 

The framework includes detailed workflows and formulae to estimate emissions across the three stages of media campaigns: creation, distribution, and consumption. It also offers tools like emissions data hacks to fill gaps when granular data is unavailable and a voluntary data request form to standardise how emissions information is collected across the supply chain.

Sebastian Munden, global chair of Ad Net Zero, explained: “We believe tracking and calculation provide the best platform for reduction, helping to inform decisions which reduce waste without decreasing effectiveness. By doing this, we aim to make a significant difference to the carbon impact of the global advertising ecosystem.”

Ad Net Zero’s updates are designed to meet growing regulatory demands, with 63% of supporters citing compliance as a key driver for adopting the framework. The GMSF aligns with international reporting standards, such as the EU’s Corporate Sustainability Reporting Directive (CSRD), and ensures that industry stakeholders can meet legal and sustainability requirements more easily.

Cinema is the final media frontier to receive fully operational emissions formulae. Ad Net Zero will continue refining the GMSF with future updates, and include audit specifications and centralised data solutions.