From the salmon-rich waters of Southeast Alaska to the white sand beaches of Florida's Gulf Coast to Downeast Maine's lobster, lumber and tourist towns, coastal residents around the U.S. share a common characteristic: their views about coastal environments divide along political lines. That's a primary finding of a new study by University of New Hampshire sociologists published this month in the journal Society and Natural Resources.

"We found a lot of environment-related differences from place to place to place. Each environment is different so that's just what you'd expect. But underneath there's a common pattern: partisanship," says Lawrence Hamilton, professor of sociology at UNH and lead author of the paper.

"On almost every issue in every place, Democrats express greater concern about environmental problems than Republicans."

"From other research we knew there might be party-line divisions, but we didn't realize they would be so pervasive on coastal issues, down to local scale," he adds.

On 35 out of 36 comparisons in one analysis, Democrats were more likely than Republicans to see environmental problems as a serious threat.

The partisan gap was the widest, ranging from 21 to 42 points, on a survey question related to climate change: concern about sea-level rise. Yet even on more local issues widely agreed to be serious - seafood contamination in the Pacific Northwest, for instance, or coastal development in Florida - partisan divides exist.

The study provides a broad comparative look, the first of its kind, at how residents of different coastal areas view the challenges and threats to their unique environment.

The researchers synthesized data from surveys of attitudes on coastal or marine environmental problems from eight U.S. coastal regions: Downeast Maine, Gulf Coast Florida, Gulf Coast Louisiana, Columbia River in Oregon and Washington, Puget Sound and Olympic Peninsula in Washington, Ketchikan and Southeast Alaska. The surveys reflect the viewpoints of more than 7,000 interview subjects.

While the political divide on environmental issues was common across geographic regions, Hamilton and co-author Thomas Safford, associate professor of sociology at UNH, found distinct regional responses to various issues. Some differences are general: in areas of high unemployment, for instance, there was less concern about global warming issues.

Where employment in resource industries like fishing was high, concern about environmental issues affecting those resources was similarly high. And where population growth is high, respondents expressed more concern about coastal development.

"If they're paving over your favorite beach, you might think we need some new rules," Hamilton explains.

Other responses were unique by region or, in some cases, within a region. On the Gulf Coast, for example, development was a prime concern in tourist-heavy Florida, while Louisianans, surveyed during the Deepwater Horizon blowout, were very concerned about beach pollution and seafood contamination.

"They're close to each other, but they're geographically different," says Hamilton. "You find these place-to-place effects that are tied to local environment-society relationships."

Hamilton surmises that the divide between Democrats and Republicans on local as well as global coastal issues speaks to increasing fidelity to party ideology, particularly as it relates to government intervention. "If something is a problem, whether it's overfishing or sea level rise or beach pollution, maybe something should be done," he explains.

"For most of those, it's hard to imagine who could do that other than government. If you reject government regulation as a solution, you work backwards to say it's not a problem."

He also suspects that polarization over climate change, which he documented in a Carsey School of Public Policy brief earlier this year, has bled over into other environmental issues. "There are people who think simply, 'If Al Gore's for it, then I'm against it,'" he says.

Hamilton notes that the partisan divide on environmental issues is a relatively new phenomenon. Much of the landmark environmental regulation of past decades - the Clean Air, Clean Water, and Endangered Species acts - were passed with bipartisan support. Now, policy on coastal environmental issues is likely to be stymied by the deep political division.

"Anyone who's trying to manage resources now is aware of how hard it is to get public support for anything that inconveniences anybody. And now there are these automatic political fault lines," Hamilton says, adding that other data from this study could help.

"Understanding local place effects could help to offset the otherwise immobilizing force of partisanship in building public support for science-based marine policies."