(Phys.org) -- The amount of "green" advertising rises and falls in conjunction with key indicators of economic growth.
That's what three Penn State researchers found when they examined 30 years of environmental advertising in National Geographic Magazine, America's leading nature publication, and compared it to what was happening with the gross domestic product at various points in time.
"Because advertisers do a lot of research into public attitudes before they create and place ads, we took advertising as a reliable proxy for environmental concern," said Lee Ahern, an assistant professor in the Department of Advertising/Public Relations in the College of Communications. "We found that changes in GDP do indeed predict the level of 'green' advertising."
Ahern, Denise Bortree, an assistant professor in the Department of Advertising/Public Relations, and Alexandra N. Smith, a doctoral candidate in the College of Communications, are the authors of a paper in the journal, Public Understanding of Science, which is available online now and is forthcoming in print. Their work was supported by a grant from the Arthur W. Page Center for Integrity in Public Communication.
The researchers learned that between January 1979 and December 2008, National Geographic ran 692 pages of "green" ads. These were defined as " ... all ads that invoked environmental protection in some meaningful way." Most were placed by corporations. Some came from advocacy organizations and business association or industry front groups.
They found a significant statistical correlation between the health of the gross domestic product and the number of green ads. For the past three decades, there has been a theorized relationship between economic well being and environmental concern (known as Inglehart's post-materialist values shift thesis). This study is one of few to offer empirical evidence of this connection.
"Marketers have their fingers on the pulse of public sentiment," Ahern said. "Using the level of green advertising as a proxy for general environmental concern, we can see that economic trends significantly produce this 'greenness' indicator."
Another thing they found was that green advertising has evolved over time, both in the types of ads that run and in the messaging.
There were, for example, no greenhouse gas ads in the first 10 years studies because global warming was not then on many radar screens. In that first decade, ads promoting the energy efficiency of products was predominant. In the period between 1989 and 1998, species and habitat preservation ads were dominant. Greenhouse gas ads began to appear in that second decade and there was a decline in energy independence messages.
"The most recent decade," said Ahern, "was characterized by a continued increase in the percentage of ads focused on greenhouse gas reduction and a decrease in energy independence messages, as well as an increase in messages that focus on the general state of the environment."
Image ads promoting corporate social responsibility have become the primary type of environmental ads run in National Geographic. Ads touting the green points of products have declined in number.
Advertising messages, Ahern says, move on a continuum. Early ads provide information or an argument and later, as a brand develops, emotional appeals predominate. That's happening with environmental advertising, too. "Green appeals have evolved over time," he said. "Now they are more emotional in nature."
The researchers found that the latest corporate-sponsored green ads studied tended to be emotional appeals aimed at linking the firm with environmental protection. Ads run by environmental advocacy groups, by contrast, tended to offer more information and argument. And the fact that corporate ads far outnumber advocacy ads has caused some "... advocacy organizations to fear that their messages are drowned in a sea of green advertising appeals."
Many have hypothesized that environmental concerns wax and wane based on economic conditions, but this study is among the first to document it.
"Results support the idea that key economic indicators affect the level of green strategic messaging," said Ahern. "This perspective argues that environmental concern will be greater in stronger economies and better economic times. By extension, consumers will be more attuned and receptive to green appeals when the economy is improving, and marketers will employ more green advertising."
The paper by Ahern, Bortree and Smith is titled "Key Trends in Environmental Advertising Across 30 Years in National Geographic Magazine."
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