Second of four parts
If the threat of more West Nile virus, smog, contaminated water, higher food prices, invasive species, toxic algae, lake level declines, and deaths from heat waves isn't enough to wake up people to problems associated with climate change, consider this: Ohio might lose its namesake nut to arch rival Michigan.
That's right. The buckeye.
Some fear the buckeye tree won't be able to handle the state's warming climate and will instead adapt to a more moderate climate in Michigan, a cruel fate of irony for Ohio's official tree.
But that may be the least of the region's concerns if other predictions about climate change come true - forecasts that go well beyond reduced opportunities for skiing, snowmobiling, ice fishing, and other forms of winter recreation.
Agriculture could become more difficult, with crop yields harder to maintain because of drier soils and more insects - and too much rain at the wrong times.
Soybeans, corn, and wheat might benefit from longer growing seasons some years, according to one University of Michigan study. But the frequency and duration of thunderstorms could make it more difficult to grow those and other crops, especially if soil bounces between extreme drought and flooding cycles.
The result could be higher food prices for the region's 42 million residents, according to George Kling, a University of Michigan biology professor involved with the study.
He also was the lead author of a 2003 report that predicted Ohio and Michigan would have extreme bouts of summertime heat by the end of the century, akin to what Arkansas experiences today, with as much as a 9-degree increase in Ohio's average summer temperature and as much as a 13-degree upward swing in Michigan's.
The frequency of thunderstorms could be doubled, yet soil is expected to be drier and more prone to drought because of the increased rate of evaporation. Ohio winters also are predicted to be 7 degrees warmer on average, with Michigan winters expected to be 10 degrees warmer on average, according to a report published by the Union of Concerned Scientists and the Ecological Society of America.
That, of course, is if no major changes occur soon to curb greenhouse gases.
The consequences nationally of doing nothing could include more Katrina-force hurricanes along the Gulf and Atlantic coastlines, more forest fires in California and other parts of the West, and more species going extinct, according to Stephen Schneider, a Stanford University biology professor who was on the report's steering committee.
"We are facing threats to the life support system of the Earth," said Mr. Schneider, one of America's top climatologists and a key figure in the Intergovernmental Panel of Climate Change's Nobel Prize-winning work in 2007.
Steep declines in hunting and fishing, cutting into the Great Lakes region's multibillion dollar recreation and tourism industries, are projected.
U.S. Rep. John Dingell (D., Mich.), the senior member of the U.S. House of Representatives, has met with sportsmen in his southeastern Michigan district to discuss the climate changes to come.
Warming could cause a 39 percent reduction in the region's duck population and a 42 percent decline in its trout and salmon habitat by the end of the century, Mr. Dingell's office said.
"I would prefer to legislate with more certainty from the scientists about the dangers we face in the future, but we do not have that luxury. Scientists are already observing effects now from climate change," said Mr. Dingell, chairman of the House Energy and Commerce Committee, at a June 26 hearing.
Failure to pass meaningful legislation to address climate change "could put the planet and our country at risk of even bigger and graver consequences," he said.
Falling lake levels
Equally important are the anticipated losses of fresh drinking water in the western Lake Erie watershed. The five Great Lakes - Superior, Michigan, Huron, Erie, and Ontario - hold 20 percent of Earth's fresh surface water.
Evaporation would more than offset the region's gains in precipitation, according to Frank Quinn, a retired hydrologist from the National Oceanic and Atmospheric Administration, who has studied Great Lakes water levels since the 1960s.
Lake Erie doesn't have the kind of ice fishing opportunities it had a generation ago, when ice was so thick that automobiles could drive safely over it by mid-winter.
Recent Januarys have produced more rain than snow, and Lake Erie froze over only sporadically in recent years, sometimes for only a month and sometimes not at all. Lakeside residents remember how the lake used to be frozen solid for three months at a time. Some recall the wintertime tradition of lining up discarded Christmas trees to mark safe routes for automobile traffic between the Lake Erie islands and the mainland.
In recent winters there was not enough ice to drive on the lake.
A 2007 report acknowledges that Great Lakes water levels have fluctuated over thousands of years but says lower lake levels "are consistent with many global climate change scenarios." The report was issued by the National Oceanic and Atmospheric Administration's Great Lakes office and Duke University.
Lake Erie is under the greatest stress when it doesn't freeze in winter. Evaporation is greatest in late fall and early winter because the difference between air temperature and water temperature is greatest then.
Ice seals off evaporation, but when it comes late or not at all, lake levels are much more susceptible to plunging because of the additional evaporation.
"The amount of ice on the lake can dramatically affect what happens to the lake the rest of the year," said Jay Austin, an assistant professor of physics at the University of Minnesota at Duluth.
Lake Erie continues to receive heat and solar radiation as long as there is open water, causing the lake to keep evaporating in winter, said Jia Wang, a Great Lakes ice climatologist at the National Oceanic and Atmospheric Administration.
'A warmer region'
"Unequivocally, we're already observing changes in the Great Lakes region," said Joel Scheraga, national program director for the U.S. Environmental Protection Agency's Global Change Research Program. "On average, it is becoming a warmer region. But I emphasize 'on average.' "
Some parts of the region, such as the Ohio River Valley, have actually cooled a bit. The same phenomenon has occurred in other parts of the country because of their unique climatic conditions. In other words, not all areas are necessarily getting warmer.
"There's a regional texture," Mr. Scheraga said. "We're seeing wetter conditions, more intense rainfall and precipitation. Some of the consequences are lower lake levels, earlier ice break-up, an early spring, and longer growing seasons. The key point here is we are already seeing changes in climate in the Great Lakes region."
The best hatches of walleye and yellow perch - Lake Erie's most prized sportfish - come after winters with good ice cover, said Jeff Tyson, a supervisor for the Lake Erie Fisheries Research Unit that the Ohio Department of Natural Resources operates in Sandusky.
Walleye and yellow perch are cool-water species. So are lake trout and brook trout. They thrive when competitors get displaced or killed off by the cold.
The lake likely will grow more algae as the climate warms, said Jeff Reutter, Ohio Sea Grant director and OSU's Stone Lab director.
Some algae is always in the water. Small blooms help block out sunlight for underwater plants that fish use as habitat, which can help spawning. But excessive amounts rob the lake of its oxygen, killing fish while causing noxious odors and driving down property values of lakefront homes.
Phosphorus runoffs from farms into the Maumee River, Lake Erie's largest tributary, have been on the rise since 1997, reversing a 25-year decline and bringing back the lake's algae problem. Phosphorus is a common soil nutrient that helps algae grow. A warmer climate could lead to more rain and more phosphorus runoff in the wintertime, officials said.
Anomalies can be found in any point of the Earth's climate history. The focus needs to be kept on climate trends, Mr. Reutter said.
The region can expect more on-again, off-again winters with a mix of rain and snow, with perhaps the biggest change being warmer winter nights that keep Lake Erie from freezing as early as it has in the past.
During summer, daytime highs in Ohio have not changed all that much yet, but evening temperatures have.
Jeffrey Rogers, Ohio's state climatologist, wrote in a report earlier this year that summer nights in Ohio are on average 3 degrees warmer than they were in the 1960s, most likely because of climate change.
"In Ohio, we don't have a clear signal of global change like you have in the Arctic, where sea ice is melting, but these rising nighttime lows are the next closest thing," said Mr. Rogers, an Ohio State University geography professor.
A dire forecast
On July 17, the U.S. Environmental Protection Agency issued the most comprehensive report it has ever published about the anticipated effects of climate change on the United States.
It predicted more smog, more deadly heat waves, more drought, and more extreme rainfall with flooding in the Great Lakes region.
Mr. Scheraga, the lead spokesman for that report, is in charge of the U.S. EPA's Global Change Research Program. He's also that agency's representative on the U.S. Climate Change Science Program. The latter is a consortium of 13 federal agencies assessing the potential impacts of climate change, the highest empaneled by the U.S. government.
Mr. Scheraga said climate change "poses real risks to human health."
He said the United States and developing countries are often "cavalier about how we can adapt to a changing climate because we're wealthy and we're technologically advanced."
Each region of the country will experience unique effects.
"There's no one size fits all," he said.
Climate-related factors are at least partially responsible for quadrupling the rate of asthma in the United States over the past 20 years, according to Dr. Paul Epstein, associate director of the Center for Health and the Global Environment at Harvard medical school and one of the nation's preeminent experts on the public health effects of cli-mate change.
Expect more sneezing from pollen and ragweed, plus a variety of other health issues from more mushroom spores, mold, and poison ivy, he said.
Portions of North America are now being affected by dust clouds emanating as far away as Africa's expanding deserts. Now that oceans have started to warm, the dust has been carried by stronger winds across the Atlantic Ocean, causing more respiratory irritants for Caribbean islanders, according to research Dr. Epstein had published in a new report issued by the National Academy of Sciences.
More plant pollen and soil fungi may be coming too. Ragweed growth under elevated levels of carbon dioxide also have been shown to grow 10 percent taller and produce 60 percent more pollen, his paper said.
A wake-up call
Major storms are expected to become more frequent and devastating as the Earth's climate warms.
Hurricane Katrina, for example, gained a lot of speed and force after ripping across South Florida and coming in contact with warm air rising from the Gulf of Mexico before slamming into New Orleans.
Katrina was not the worst hurricane in history, but it was a wake-up call in that it showed Americans how unprepared some of its major cities were for handling disasters.
It served as a wake-up call in another sense too - that more such disasters could be in the making as gulf water and ocean currents continue to warm.
Mr. Scheraga said more hurricanes and other climate-driven disasters "may impose the greatest challenge to public health" because of what they put into the air, as well as the mold they leave behind after floodwater recedes.
Floods are often followed by outbreaks of disease and sicknesses, as downpours force rodents out of their burrows, disperse mosquitoes, and promote the growth of fungus. Major coastal storms trigger harmful blooms of toxic algae, which can lead to "dead zones" in waterways because of a lack of oxygen, according to the National Academy of Sciences.
The Great Lakes are not immune from such effects. Just last month, remnants of Hurricane Ike left much of southern Ohio and other parts of the Midwest under water and without power for days.
Residents of Findlay and Ottawa, Ohio, are still cleaning up from record floods in 2007, with the Hancock County commissioners last month voting to raise the county's sales tax to pay for flood-control projects.
The Great Lakes region is woefully behind on sewage-treatment needs, largely the result of sprawling growth patterns that have pushed antiquated systems well beyond their capacities. Cities that can't handle a rush of rainfall end up releasing tons of untreated waste into streams to keep homes from flooding.
Congress is now considering legislation to fund more than $10 billion in sewage treatment projects in the Great Lakes region.
But is that enough? Mr. Scheraga said Great Lakes communities may find such vast projects, even if they are ever funded, falling short of keeping pace with the impacts of climate change.
"In other words, they will not be getting the intended outcomes," he said.
Some people, though, question if the focus on hurricanes and tornadoes diverts too much attention from the more immediate and simple problem of prolonged heat exposure.
Heat waves typically kill more people than hurricanes and other climate-related events combined. Those at greatest risk are the poor, the sick, and the elderly - people who often lack access to air conditioning.
That can be especially true in northern states where air conditioning is not considered as essential as in the Sun Belt.
A report produced by the federal EPA's office of research and development stated it is "very likely that heat-related illnesses and deaths will increase over the coming decades."
The agency said that is especially likely in the Northeast and the Midwest.
Though it did not project numbers for future heat-related deaths, it noted there were at least 4,780 deaths resulting from heat waves between 1979 and 2002.
That figure was likely underestimated because heat is seldom listed on a death certificate. And heat often exacerbates chronic health problems, such as heart, renal, and lung diseases, and diabetes, the report stated.
The Great Lakes region will likely see more heat waves like the one in 1995 that killed 700 people in the Chicago area, according to Don Wuebbles, a University of Illinois professor of atmospheric sciences.
He said he expects Illinois to warm so much by the end of the century that it feels like eastern Texas does today, and for Minnesota's frigid climate to someday have the extreme summer heat that is found these days in Kansas.
As temperatures rise, expect more mosquitoes carrying the West Nile virus into the Great Lakes region, Dr. Epstein said.
Ticks carrying Lyme disease and other diseases have been found to move north as winters become warmer, while mosquitoes - which carry many diseases other than West Nile - reproduce in greater numbers and stay around longer. They have already been found moving to higher ground in mountainous regions as permafrost thaws and glaciers retreat.
There are numerous biological changes in store given the fact that the oceans have absorbed 22 times as much heat as the atmosphere since 1957. That has resulted in more water vapor and hot air rising, Dr. Epstein said.
Assessing the risk
How good are the projections?
Scientists give themselves mixed reviews.
"Scientists tend to be conservative. Most of the predictions you see are going to be underestimated," said Daniel Schrag, director of Harvard University's Center for the Environment. "[But] this whole assumption that we scientists know what the Earth's system is going to do is crazy."
Linda Mortsch, a Canadian who authored a chapter of the Nobel-winning Intergovernmental Panel on Climate Change report, agreed that predictions have been made by "extremely conservative" scientists who are leery of overcommitting themselves.
But there are signs of problems emerging for the Great Lakes region as far west as Colorado, where the devastating mountain pine beetle is thriving.
Canada, the world's largest source of pine trees, is on guard for them. Because of a warmer climate, the beetle appears capable of crossing the Continental Divide and ruining Canada's pines. It is expected to come south from Canada into Minnesota, Wisconsin, and Michigan.
A warmer climate also makes latent problems such as algae worse, said Ms. Mortsch, former head of the Canadian Climate Centre's lakes climatology unit and now a senior researcher of the adaptation and impacts research group for the Meteorological Service of Canada.
"That's the one thing I can tell you for sure, that the climate's going to be changing in the future," she said.
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