The use of online ad blocking software, which is growing by double digits globally and is now moving into mobile as well as desktop devices, could cost marketers nearly $22 billion this year, according to a new study from PageFair and Adobe. Unless publishers can find better ways to earn revenues, ad blocking's rapid growth poses an "eminent threat" to the Web as we know it, PageFair's co-founder and CEO said.

Worldwide, the number of people using ad blockers over the past 12 months has grown by 41 percent, to 198 million monthly active users, according to the study released today. The use of ad blocking has seen even faster adoption in the U.S., which experienced a 48 percent increase to 45 million users -- about 16 percent of the country's entire online population -- between Q2 2014 and Q2 2015.

"The Cost of Ad Blocking" report predicts that $41.4 billion in online advertising will be blocked globally by 2016, with nearly half of that amount -- $20.3 billion -- affecting online ad revenues in the U.S. Based in Ireland, PageFair was founded in 2012 to "help create a more sustainable advertising ecosystem" that supports online revenues for Web sites without alienating users.

A 'Threat' to the Open Web

"It is tragic that ad block users are inadvertently inflicting multi-billion dollar losses on the very Web sites they most enjoy," said PageFair CEO and co-founder Sean Blanchfield. "With ad blocking going mobile, there's an eminent threat that the business model that has supported the open Web for two decades is going to collapse."

The use of ad blocking software is especially prevalent among users who are young, technically savvy and more typically male, according to PageFair's third annual study. Those demographics are reflected in the types of sites most likely to see their ads blocked: gaming sites come in at number one, with an average global ad blocking rate of 26.5 percent, followed by social networking (19.1 percent), tech/Internet sites (17.0 percent), education (16.9 percent), sports/recreation (15.5 percent) and financial services (13.3 percent).

"By working with PageFair, our goal with this research is to shed light on the effects of ad blocking so the industry can develop better solutions for content publishers, advertisers and consumers alike," said Campbell Foster, director of product marketing for video solutions at Adobe.

Johnny Ryan, PageFair's innovation and sustainable media leader, told us the new report makes it "clear that publishers must address the crisis posed by ad blocking in a new way."

Ryan compared the current state of online publishing to that of the music industry in the early 2000s, when startups like Napster began challenging that industry's status quo.

"Ultimately, even despite successful legal action against Napster and others, that industry was forced to opt into a set of rules imposed by Apple because the music labels failed to give digital consumers a viable alternative to piracy," said Ryan, the author of "A History of the Internet and the Digital Future." We do not want to see publishers make the same move into apps and walled gardens like Facebook. We believe that the open Web of freely available content paid for by audience attention can be saved."

'Users Demanding More Say'

"I can definitely tell you that we are seeing a steady, high download rate of Adblock Plus (upwards of 3M per week), and increased demand from our users for additional mobile solutions," Ben Williams, a spokesperson for the Germany-based ad blocking software company, told us. "It's exciting that users are demanding more say in their online experience, and it demonstrates where the wind is blowing: toward total user control."

That wind is likely to begin blowing more in the smartphone and tablet space with the coming fall release of Apple iOS 9. Noting that the new mobile operating system will allow users to easily install ad blocking via Apple's iTunes App Store, the PageFair-Adobe study said iOS 9 "may be a game changer."

"Makes sense -- mobile is the next logical step for ad blocking," Williams said. "Things like Apple's announcement just prove that ad blocking is going mainstream."

In the afterword to this year's study, Blanchfield noted that online advertisers cannot win a "cat-and-mouse" battle with ad blockers.

"A deeper problem is that ad blocking is endemic only because online advertising has become so invasive that hundreds of millions of people are willing to take matters into their own hands," he said. "To sustainably solve ad blocking, we must treat these users with respect, not force feed them the popovers, interstitials and video ads that they are trying to get rid of."