BAYFIELD -- An idea from his dad and a push from his science teacher led Forrest Howk to uncover what may be some of the most dramatic evidence yet of a warming Northland climate.

Howk, a high school senior, this year researched ice cover between Bayfield and Madeline Island from 1857 through 2006, scouring records from the Madeline Island Ferry Line back to 1964 and then going back a century further, looking at hundreds of newspaper accounts from the old Bayfield County Press.

He wanted to know when boats made the last run each winter, when hard ice formed, and when the first boat made it through each spring when ice broke up.

Here's what he found:

* There is now about 45 days less ice cover on average than in 1857, the year Bayfield was founded and freeze records began.

* Ice cover has been declining at an average of one-third day each year for 150 years.

* From 1907 to 2006, average ice cover declined by a full month -- 31 days.

* Over the past 25 years, the decline in ice cover has been more dramatic, losing a day of ice cover every year.

* Three of the four shortest ice seasons have been in the past 10 years, including 1997, the only year in which ice did not form between Bayfield and the island.

Howk last week showed how computer plots of the dates show the lines between ice cover and ice out getting closer. Those lines likely will merge before Howk turns 50.

"The projection shows, if the trend from the last 25 years holds, there will be no ice cover at all in 30 years,'' said Howk, 17.

The findings aren't unexpected among researchers already looking at indicators and effects of climate change. University of Minnesota Duluth scientists earlier this year found that Lake Superior water temperatures are increasing at a rate even faster than Northland air temperatures.

Howk's findings echo similar studies, including by University of Wisconsin limnologist John Magnuson, that show Northern Hemisphere lakes are ice-covered weeks less than a century ago.

In fact, Magnuson helped Howk take raw data and plot the information on computers to show trends.

The more rapid decline of ice in recent decades also isn't unexpected. Scientists around the globe are saying their research shows climate change increasing quickly.

"I'm impressed with how he did the historical research to dig out the data, and that he found so much about the history of the early residents of the area,'' Magnuson said. "It's not a new finding that we have significantly less ice, but it's a new aspect of that. ... I think he can publish this.''

Gets the nudge

Howk was spurred by his science teacher, Rick Erickson, to enter a regional science symposium for Wisconsin and Upper Michigan held earlier this month in La Crosse.

"I open it up to anyone, but I don't push them into it. It takes a self-motivated kid to do this, and that's Forrest,'' Erickson said.

Forrest got the idea for the project from his dad, Neil Howk, who is assistant chief of interpretation at Apostle Islands National Lakeshore.

"We all know about Glacier National Park and how the glaciers are disappearing and will be gone soon, and the polar ice cap melting," Forrest Howk said. "I wanted to see what we had at home where we could look at what was happening here.''

Ice cover between his hometown and the island seemed to fit.

Judges agreed. The project took first place in the LaCrosse event, earned him a $2,000 college scholarship and will send him on an all-expense paid to the National Science and Humanities Symposium next April.

Howk continues a tradition at Bayfield High School, which has sent five students to the International Science and Engineering Fair and three to the National Science and Humanities Symposium in recent years.

Howk and his dad spent dozens of hours poring over old newspapers on microfilm. In most cases, the last day of boat travel in the fall and the first day each spring made front-page news in a town and era closely linked to the big lake's fishing and shipping.

"Usually it was easy to find. But sometimes it was way back in the chit-chat column. We looked at a lot of newspaper stories,'' said Howk, who's become a quick expert on the region's early history. "You find out how important the ice was to people back then.''

In decades past, the passage between Bayfield and the island would freeze up by mid-January and stay frozen for ice travel almost to April 1.

Now, recent ice seasons have ranged from just 7 days to 11 days to no days at all.

"The first day [of ferry travel in spring] has moved a little earlier. ... But the real change has come in the first day'' of ice cover when boats can't break through, Howk said. That indicates warmer air and water temperatures in fall and early winter are delaying, or preventing, the lake from freezing.

Most everyone around the Apostle Islands and Lake Superior already had a hunch that the lake didn't freeze as much as it used to. But the implications of this major change haven't been fully calculated.

Less ice road, more ferry

Already, the Madeline Island Ferry Line must operate more weeks in the winter at a loss. There isn't enough traffic to pay for the ferry's operating costs, but the boats must keep running or Madeline Island's 270 residents would have no way to reach the outside world.

That means higher fares for everyone during busier summer months to cover the winter loss. And it means passengers must pay steep ferry ticket fees rather than drive their own vehicles over a free ice road.

"It's not in our business plan to operate all year, but that's where we're headed,'' said Mike Radtke, a captain for the ferry line. "And it's more money for the people [island residents and visitors] because they can't use their own vehicles to go back and forth during the winter.''

The lack of ice also means more evaporation of Lake Superior water and could be contributing to near-record low water levels, some scientists say.

Most scientists who study the causes and effects of the warming climate say the temperature increases can't be explained by natural phenomenon, such as sun strength or volcanic activity.

The overwhelming conclusion is that greenhouse gases generated by human activity, such as carbon dioxide and methane, are warming the earth.

"It's going to affect fishing, commercial fishing and tourism. There's a lot of things here [along Lake Superior] that will be affected by this kind of change,'' Howk said.

Magnuson said Howk's research is similar to data that goes back to the 1450s, when ice dates were recorded by Japanese Shinto monks -- part of a long line of lay-person accounts of climate that have become invaluable as the issue takes center stage.

"There's no way to certify that any of these records were correct,'' Magnuson said of historical ice accounts. "But taken together, the magnitude of change they show is so much greater than you could possibly have from observer error, that they become completely credible.''

Howk said he considered other factors that may have affected the first and last boat passage each year. He looked at the change from wooden to steel boats, but noted that the biggest loss of ice cover has come since the 1960s -- well after the current model of steel-hulled boats were in service.

Howk is considering science for college studies, but he's not sure yet. He also played soccer, basketball and baseball (before knee surgery), participates in forensics and band, and was Bayfield High School's representative at Badger Boys State.

Oh, and he's also the senior class president.

Howk says he wants to add to his report before the national competition, possibly looking at air temperature records around the Apostle Islands to see how they relate to the diminishing ice cover.

"It's one thing to hear about something in Montana or in the Arctic,'' Howk said. "But to have this happening in our own back yard, that's kind of scary.''