Global warming may affect tourism

Scientist James Lofgren of the National Oceanic and Atmospheric Administration’s office in Ann Arbor discusses the effects of global warming on the Great Lakes region during a presentation Thursday at Siena Heights University in Adrian. — Telegram photo by

Increasing temperatures and changes in the overturning of water in the Great Lakes are due to global warming.

By David Panian

Daily Telegram Staff Writer

ADRIAN — Tourism and shipping in the Great Lakes region could be affected by the warming of the Earth, a National Oceanic and Atmospheric Administration scientist told an audience Thursday in Adrian.

Increasing air and lake temperatures, changes in the “overturning” of water in the Great Lakes, less ice and changes in the seasonality of water runoff are all likely due to global warming, Brent Lofgren of NOAA’s Ann Arbor office told the audience at Siena Heights University. He was speaking as part of “Focus the Nation,” a teach-in at schools across the country.

“I’m here to present you with what we believe are the best scientific facts,” Lofgren said.

Winter temperatures in the Great Lakes region are expected to increase during the 21st century from the current 34 degrees average to 43 degrees, Lofgren said, with winter precipitation increasing from about 22 inches per year to about 30 inches per year.

“That’s not necessarily snow,” he said. “If it’s rainfall … that converts runoff into lakes at a different time of year (than usual).”

It could mean less runoff into lakes and streams in the spring.

How that would affect lake levels is unclear, Lofgren said, explaining that some studies show lake levels increasing and others show them declining.

“My opinion is that it is more likely to go down in the next 50 years,” he said. “After that it may change.”

Should lake levels decrease, that could affect shipping, Lofgren said, as ships would have to carry less cargo in order to navigate the shallower waters.

However, he said, many lakefront property owners like having the wide beaches created by lower lake levels. Then again, pleasure boaters tend to like higher lake levels that keep the water closer to their existing docks.

Less ice would also affect shipping lanes as well as animals’ winter habitats, he said.

With changes in water temperature and the thermal structure of the Great Lakes come possible changes in the suitability of the water for the animals and other organisms that live in them, Lofgren said. The lakes also currently “overturn” twice a year where the water inverts and mixes nutrients from the lake bottoms throughout the water. That could change to only once a year, he said.

Global warming is caused by the collection of various kinds of gases in the atmosphere, primarily carbon dioxide, nitrous oxide, methane, chlorofluorocarbons and water vapor, Lofgren said. Those gases help retain infrared radiation rather than letting that which reflects off the Earth to return to space. Water vapor is a significant contributor to global warming because it is caused by warming.

“If it wasn’t there, the warming due to carbon dioxide would be quite small,” he said.

There have been models explaining global warming since the 1960s, Lofgren said, with those models becoming more detailed over time. Now they have atmospheric gases broken down into various types, with some acting as coolants, and take into account non-atmospheric changes, such as changes in vegetation growth.

The relationship between the greenhouse gases and coolants can be tricky, Lofgren said. For example, he said sulfate aerosols are emitted by automotive exhaust along with carbon dioxide. While the sulfate aerosols reflect heat radiation before it gets to the Earth, it may only be masking the true effects of the carbon dioxide. Lofgren explained that the sulfate aerosols stay in the atmosphere for only a few weeks while carbon dioxide remains much longer. He said if automotive emissions were to be completely reduced, the sulfate aerosols would dissipate, leaving the longer-lasting carbon dioxide behind without the cooling effect of the sulfate aerosols.

As part of the teach-in, a panel of Siena and Adrian College students talked about what students can do to protect the environment.

Sharon Parks, an Adrian College senior, suggested eating and shopping locally, meaning buying food and products made within 100 miles. She said that would promote Michigan businesses and use fewer resources to transport the goods. She also said students should learn at least a little bit about environmental issues because they can be put to use in their future careers.

Cat Griebe, an Adrian sophomore, talked about her experiences at the Power Shift 2007 conference in Washington and lobbying Congress to pass legislation to reduce carbon emissions, not allow new coal-fired electricity plants and promote “green” jobs. She encouraged Thursday’s attendees to write letters to their representatives in Congress and to join or start environmental groups on their campuses.

As an alternative to using plastic drink bottles, Siena junior Kayla Palmer suggested using a reusable stainless steel bottle. She said getting away from plastic bottles would reduce the amount of energy used to make and ship them.

Siena junior James Felan promoted recycling, shopping locally and using products made from organic materials. He suggested they make even small changes in their lifestyles, including recycling and turning off lights in unused rooms.

“As students … college is a time where you develop habits that will carry through your lives,” he said. “If we can all take small steps together, it’s one large step.”