Climate change makes it harder to save Lake Erie

Heavier rains cause runoff, feeding algae

9/29/2014
BY TOM HENRY
BLADE STAFF WRITER
Thick algae washes up on the beach at Maumee Bay State Park. Scientists say climate change will exacerbate the factors that cause toxic algae blooms on Lake Erie.
Thick algae washes up on the beach at Maumee Bay State Park. Scientists say climate change will exacerbate the factors that cause toxic algae blooms on Lake Erie.

Although not the primary source of Great Lakes algae, climate change is exacerbating the problem and making it harder to reduce phosphorus and other nutrients that help algae grow, experts say.

National Oceanic and Atmospheric Administration records show a 51 percent increase in heavy storms — those that dropped 3 inches of rain or more within 24 hours — in the Midwest since the 1960s.

Jeff Reutter, Ohio Sea Grant and Ohio State University Stone Laboratory director, cited erosion, nutrient loading, harmful algae blooms, invasive species, oxygen-depleted “dead zones,” and climate change as Lake Erie’s six biggest issues at an Ohio Farmers’ Union presentation in Toledo last Monday.

“Climate change makes all of them worse,” Mr. Reutter said.

He and other members of a special task force the state of Ohio has had looking at the phosphorus issue in recent years have concluded that western Lake Erie’s algae blooms could be brought under control within two or three years — being shallow, western Lake Erie tends to respond quickly to improvements — if northwest Ohio farm and street runoff, as well as sewage spills and other sources of nutrients, were reduced by 40 percent.

That’s the task force’s goal.

“It’s a fixable problem,” Rick Stumpf, a NOAA oceanographer in Maryland studying Lake Erie’s algae outbreaks via satellite, told reporters at Stone Lab in July.

But even if a 40 percent nutrient reduction is somehow achieved in the short-term, scientists said it’ll be an uphill battle preventing recurrences if the United States, China, India, and other countries producing the majority of the world’s greenhouse gases don’t come to terms on a meaningful plan to reduce them globally.

Ohio, with its heavy reliance on coal-fired power, plays a big role in that global debate.

Last winter was Toledo’s snowiest on record and coldest in years, and the summer just ended was relatively mild. Yet NOAA records show 2013 was globally one of the hottest years on record and this August was the hottest August that NOAA has on file for records dating back to 1880, all of which makes it more difficult for Toledo-area residents to understand the problem’s magnitude.

“We tend to look at climate change very, very locally. We need to look at it globally,” Mr. Reutter said.

James Zehringer, Ohio Department of Natural Resources director, expressed frustration about the situation when the Ohio Lake Erie Commission held its quarterly meeting Thursday at the Ottawa National Wildlife Refuge near Oak Harbor, Ohio.

The Kasich administration supports efforts for more cover crops, buffer strips, and damlike control structures on farmland. The first two help prevent runoff, while the control structures allow for better-timed releases of water from drainage tiles. The ODNR is assisting with those programs.

But it might not be enough.

“The thing we can’t understand is why we are getting these massive rain events we didn’t get before,” Mr. Zehringer told the commission.

About 50 Great Lakes journalists met Sept. 19 with numerous scientists during an event focused on Great Lakes climate change. It was sponsored by the Metcalf Institute for Marine and Environmental Reporting, part of the University of Rhode Island’s graduate school of oceanography.

Don Wuebbles, a University of Illinois atmospheric sciences professor who was part of the 2007 Nobel-winning Intergovernmental Panel on Climate Change team, said a 1.5-degree increase in Earth’s temperature over the last 50 years “can only be attributed to human activity.”

“It is not the sun, as deniers say,” Mr. Wuebbles said. “It’s a very clear trend that’s occurring, particularly here in the Midwest.”

Greenhouse gases that get trapped in the atmosphere cause more of the sun’s solar energy to be retained.

“What we’re doing is like adding an extra blanket. The net effect is the Earth should warm, and that’s what is happening,” Mr. Wuebbles said.

One of the problems with climate change is that its effects on precipitation aren’t evenly distributed across America or the world.

California, for example, is mired in an extensive drought, while the Great Lakes region — one of the most water-blessed in the world — gets pounded by more rain.

“The tendency is for the wet to get wetter and the dry to get drier,” Mr. Wuebbles said.

Scientists said it’s not just a matter of precipitation volume, though. A key point is the type of storm. Those that dump 3 or more inches of rain within 24 hours aren’t well absorbed by soil, resulting in a lot of nutrient runoff.

Julie Winkler, a Michigan State University geography professor, said heavy precipitation is not evenly distributed from one season to another, either.

Average temperatures have increased in the Midwest since 1900 too, she said.

Barring a rapid reduction in greenhouse gases, the “number of days with heavy precipitation should continue to increase for the rest of this century,” Ms. Winkler said.

But people need to be careful how much they attribute to climate change.

Evidence strongly links the number and strength of today’s hurricanes to climate change, for example, though no single hurricane or other weather-related event can specifically be attributed to it.

The jury’s still out on tornadoes, the Midwest’s most notorious severe-weather event.

Tornadoes are a freakish event and hard to study because they form and die out so quickly. Largely a result of warm and cool air masses colliding, they don’t consistently form under nearly identical circumstances.

“What we’re really talking about here is climate-change forensics,” said Peter Snyder, a University of Minnesota climate scientist.

Drew Gronewold, a hydrologist and physical scientist at NOAA’s Great Lakes Environmental Research Laboratory in Ann Arbor, said the Great Lakes only recently returned to historic average water levels even though the region’s annual precipitation has been above average nearly each of the last 15 years.

That’s because evaporation had a greater effect on lake levels than rain or snow up until last winter’s massive ice and snow — which, after 15 years of low water, replenished the lakes back to average levels, he said.

“There’s been less cloud cover for the past 15 years, allowing more solar energy to penetrate the water and keep the lakes warm,” Mr. Gronewold said. “This month is likely to be the first month in 15 years that all of the Great Lakes are expected to be at or above their historic averages.”

Climate change has the potential of wreaking havoc on anything from public health to food production, with the possibility of more mosquito-borne infectious diseases, air pollution, asthma, and crops either flooded or devastated by drought in the Great Lakes region, scientists said.

It also could impact fisheries. Recreational fishing, which is more common in United States waters, has a $7 billion economic impact on the Great Lakes region, while commercial fishing, which is more prevalent in Canada, is valued at $20 billion.

How much can be directly attributed to climate change remains open to debate.

“It’s hard to tell when somebody had a heart attack and dies if that’s from heat or if that person would have died otherwise,” Tracy Holloway, a University of Wisconsin environmental studies professor, said.

Karen Sands, sustainability manager for the Milwaukee Metropolitan Sewerage District, said many Great Lakes cities don’t have infrastructure prepared for more acute effects of climate change coming this century, such as heavier and more intense rainfall — which also could exacerbate algae problems.

“You don’t typically design a sewer system for the largest storm you’ve ever seen, because of costs,” Ms. Sands said. “You have to put the crystal ball on the table and try to figure that out.”

Part of the problem might be how people think of climate change.

Patrick Parenteau, a law professor at Vermont Law School, told The Blade at the recent Society of Environmental Journalists conference in New Orleans that people should stop calling the phenomenon by that name.

“We should be calling it ‘climate disruption,’ ” he said. “Because that’s what it is. It’s the disruption of our preconceived notions of what our climate should be. We should stop calling it climate change. People often think of change as something good.”

He echoed that sentiment during a video conference with reporters last week.

“This is profound. There’s nothing simple about this,” Mr. Parenteau said of the challenge. “We’re going to suffer significant harm from what we’ve done so far.”

Contact Tom Henry at: thenry@theblade.com, 419-724-6079, or via Twitter @ecowriterohio.