Media's Green Dream of Decarbonization Hits Roadblocks

Measurement challenges, lack of standards make implementation elusive

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In 2022, the global conversation about the role of corporations ebbing the climate crisis finally reached the marketing world.

In January of that year, ad-tech pioneer Brian O’Kelley co-founded Scope3, a company aimed at helping the digital advertising industry measure and reduce its carbon emissions. In July, GroupM, the world’s largest media buyer, released a global framework for measuring the carbon emissions of the media supply chain. Later that year, U.K. trade body Ad Net Zero, which aims to help the advertising industry address climate change, announced it was working on creating global standards on media decarbonization after the group launched its global expansion at the Cannes Lions International Festival of Creativity.

One year later, implementation of media decarbonization remains elusive, according to conversations with more than half a dozen industry sources. While there is more recognition of the role of digital advertising in contributing to climate change, and some early movers have made strides, further progress is held back by challenges in measurement, a lack of standards and a persistent lack of awareness about the connection between media and sustainability in the broader advertising sector.

“This isn’t a robust conversation in the space,” said Danielle Azoulay, a sustainability consultant who has held executive positions at companies like Bed, Bath and Beyond and L’Oréal. “The folks that are internally responsible for media buying don’t really concretely understand how their function can play in contributing to sustainability.”

Media has not always been an area of focus for climate change activists, and its level of carbon impact pales in comparison to industries like oil and gas and agriculture.

Nonetheless, digital advertising creates carbon emissions; extra energy can be expended depending on how a website is designed, how many ad requests a publisher sends and how many ad-tech vendors those requests run through. While data on the carbon impact of digital advertising is a hard number to come by, the internet contributes to about 3.7% of global greenhouse emissions, similar to the emissions produced by the airline industry, according to a 2020 BBC report. Programmatic advertising generates 215,000 metric tons of CO2 every month across five major economies, equivalent to 24 million gallons of gas consumed, according to recent data from Scope3.

Measuring, reducing, offsetting

Broadly, the main pillars of media decarbonization require measuring existing emissions, reducing those emissions and paying to contribute to carbon offsetting projects.

To clean up its media plan, household products company iRobot works with Scope3 and Sharethrough, which offers a Green PMP product that targets low-emission, direct-only inventory and offsets the remaining emissions of a campaign with carbon removal efforts. IRobot pays a higher CPM though the costs of carbon offsets can also be shared by the ad-tech firm and the publisher. IRobot is not working currently on a campaign that cuts out publishers according to emissions, though that is under consideration, said iRobot digital media strategist Jennie Mucciarone.

“The end goal is to cut out the bad actors and to cut out high carbon domains,” she said.

GroupM is getting closer to this goal, recently running a campaign costing $124,400 (£100,000) that removed hundreds of publishers with overly bloated carbon emission rates. The agency removed 29% of emissions and exceeded the core campaign performance KPI by 30%, which included conversions.

The carbon emission piece is so new to the market I don’t know how much advertisers have fully bought into the idea.

Anjlee Majmudar, vp of programmatic, Brainlabs

Proponents of media decarbonization want to make the case that removing carbon from media supply chains is good business, too. Scope3 is also a proponent of another ad-tech trend, supply path optimization (SPO). This growing movement is meant to help buyers create more direct and efficient media supply chains. More direct supply chains lead to fewer dollars spent on middlemen, and websites with fewer ad slots are theoretically more premium, creating a better experience for the user and the advertiser. Fewer middlemen and fewer ad slots also mean lower carbon emissions.

There is some research that bears out this vision. A November 2022 study from Scope3 and media investment analysis firm Ebiquity analyzed over $375 million of ad spend and found that 15% went toward junky “Made for Advertising” websites. These websites generated 26% more emissions than non-MFA websites. Meanwhile, trusted news websites, as determined by the Global Disinformation Index, generated 52% fewer emissions than MFA websites.

Too much data to prove a direct correlation

Despite some findings that clean media can lead to good business outcomes, not all the data proves a direct correlation, leaving some media buyers skeptical.

“There’s no linear relationship between the emissions that a [brand’s ad] produces and its effectiveness,” consumer neuroscientist Shannon Bosshard told Adweek in March. 

Bosshard led a report from ad-tech firm GumGum, which found that ads driving higher attention metrics also had lower carbon emissions. But the link between digital advertising and carbon emissions could only be clarified by finding the right intervening variable, Bosshard said.

IPG-owned Kinesso found that removing high carbon emitters did not have any negative impact on KPIs. But the agency still lacks the tools to optimize toward sustainability at scale, said Jean Fitzpatrick, svp of North America addressable investment at Kinesso.

“Today, we have to sync carbon emission data to post-delivery data,” she said, noting that matching data sets require maintenance. “Today, there is not a button to press within the platforms that automatically optimizes on carbon data.” 

Fitzpatrick still believes the future of SPO initiatives are rooted in sustainability.  “As the automation ramps up, we’ll be able to do it more broadly,” Fitzpatrick added.

Publicis Groupe, an early mover in measuring media’s carbon impact, is also taking a measured approach when evaluating the scope of media decarbonization efforts.


In 2017, the agency created a tool called ALICE (Advertising Limiting Impacts and Carbon Emissions), which reviews carbon emissions on all client projects, including, though not limited to, media. Since its launch, the tool has been used for 180 clients. The agency said it has been able to make reductions of up to 50% in energy consumption.

Still, Yale Cohen, evp of global digital standards at Publicis Media Exchange said he wouldn’t advise media buyers to make rigid exclusion and inclusion lists of publishers based on emission data alone. It can be hard to track and isolate one campaign in a large flow of data.

And the data that does exist is concentrated on publishers available on the open web, not within the walled gardens, where much of digital advertising budgets are spent.

It’s hard. You have to try to figure out where you can make the most impact.

Geoff Litwer, vp, Tinuiti

“We’re not getting it for social and search,” said Mary O’Brien, programmatic media director at PMG digital agency. “That’s a long-term challenge we would need to solve.”

Even so, Scope3 is talking to all the major players, who range from curious to engaged, said O’Kelley.

Another challenge is that there is currently no universal standard to measure the carbon emissions generated by media, as trade bodies and agencies hammer out standards.

“I can empathize [with publishers and platforms that say], ‘I don’t know if I can give you this data,’” said Krystal Olivieri, global chief innovation officer of GroupM and Choreograph, on a recent Green Media Summit panel. “It’s not feasible for them to operationalize.”

A lack of awareness hampering action

Even if standard metrics for carbon emissions existed, for many agencies, the toughest challenge is a lack of knowledge among clients.

“We don’t have a client yet that is specifically optimizing toward or against it,” said Anjlee Majmudar, vp of programmatic, North America, at performance agency Brainlabs, noting the agency offers options like green PMPs and is measuring carbon emissions to develop benchmarks. “The carbon emission piece is so new to the market, I don’t know how much advertisers have fully bought into the idea.”

Demand-side platform Adform estimates that fewer than 5% of requests for proposals have any mention of sustainability, said vp of sales, America Joseph Dressler on a Green Media Summit Panel.

For some agencies, media decarbonization is one of many corporate responsibility priorities for brands, which have to choose the causes they want to prioritize, said Geoff Litwer, vp of programmatic and display media at performance agency Tinuiti.

Brands must choose between efforts to stop “funding extremist websites or polluting the Earth or making inequality worse,” said Litwer. “It’s hard. You have to try to figure out where you can make the most impact.”

And while there are multiple announcements of companies working with providers to help with decarbonization efforts, evidence of impact is harder to come by, resulting in a classic chicken-and-egg problem, said Vivian Chang, head of the DTC practice at Clorox, at the recent Green Media Summit event.

“More of those examples would move the needle to enable tests,” Chang said.

Correction: An earlier version of this article misstated a quote from Krystal Olivieri. The quote should say that Olivieri can empathize with platforms and publishers, rather than with brands, about their ability to provide data.

This story is part of Adweek’s The State of Sustainability digital package, which spotlights climate-focused marketing solutions across the beauty, experiential and media spaces, and examines how an industry that was built to drive consumption is adapting to reduce its impact.