By Kathiann Kowalski for Inside Climate News.
Broadcast version by Farah Siddiqi for Ohio News Connection reporting for the Solutions Journalism Network-Public News Service Collaboration

Lake Erie's harmful algal blooms have started sooner and had longer peak periods over the past decade compared to earlier years, newly released data shows. Warming temperatures linked to climate change are a cause, according to researchers for NOAA's National Centers for Coastal Ocean Science, with interactions among species likely playing a role as well.

The NOAA scientists discussed the shift and forecast a moderate to above-moderate algal bloom for the lake's western basin this summer during a briefing last month at Ohio State University and Ohio Sea Grant's Stone Laboratory, off the coast of Put-in-Bay on Lake Erie.

Algal blooms occur when cyanobacteria, or blue-green algae, grow out of control due to a combination of excess nutrients, weather patterns and other ecological factors. The blooms can be a serious public health problem because some types of cyanobacteria produce toxins. Microcystin, for example, can lead to skin rashes, gut problems and liver and kidney issues. Relatively high levels of it in August 2014 prompted a two-day shutdown of Toledo's public water supply, which comes from Lake Erie.

"We were certainly caught off guard, and the impact was hundreds of thousands of people were without drinking water," said Sean Corson, director of the National Centers for Coastal Ocean Science. The total economic impact of the 2014 water crisis was around $65 million, he said.

Even when toxic strains aren't the problem, algal blooms can still affect Ohio's lake-focused businesses and other activities. Aside from the ugliness of neon green scum, people can't distinguish between toxic and non-toxic strains by eye. Such uncertainty discourages lake-based activities, such as beach visits and fishing. Blooms also add to costs for water treatment plants.

Out-of-control cyanobacteria don't provide good eating for the rest of the lake's food web, either. And they contribute to so-called dead zones, areas with very low levels of dissolved oxygen that can't support aquatic life.

For more than a decade, NOAA has worked with partners in the state, including the Ohio Sea Grant Program, the National Center for Water Quality Research at Heidelberg University, the Ohio State University and the University of Toledo, to forecast the severity of the blooms in Lake Erie's western basin. It's the shallowest part of the lake, with abundant fish. Water is likely to warm faster and blooms flourish there more readily than elsewhere in the lake. Water in Lake Erie generally moves from west to east.

Last year's bloom was significantly larger than the smaller-than-average event researchers had predicted. So the forecast team took a closer look at the data.

From 2012 through 2023, Lake Erie's algal blooms have generally started in July, compared to the previous decade when blooms usually kicked in during August, said NOAA oceanographer Rick Stumpf, who plays a leading role in the forecasting program. The lake's algal blooms during the past decade also have had longer peak periods, resembling plateaus instead of short spikes.

"Blooms are starting earlier. They're lasting longer. Their peaks are larger. So, by some measures, they're getting worse," Corson said.

"Temperature is the overall driver," Stumpf said, noting ongoing trends of warmer summers and less ice cover in winters. But it's not a simple matter of warmer water producing the changes. The team's current hypothesis is that the shift to earlier algae blooms with longer peak periods reflects both climate change and ecological interactions.

Diatoms are a type of single-cell algae found in Lake Erie, which play an important part in its food webs. They generally outcompete cyanobacteria for nutrients early in the season, when water is cooler, Stumpf explained. The diatoms provide good eating for tiny lake organisms called zooplankton. Changing conditions in the lake could be increasing the degree to which the zooplankton multiply and feast on the diatoms, perhaps suppressing their populations sooner than in earlier years. By the time that happens, cyanobacteria, which prefer warmer water anyway, may have a clearer path to use extra nutrients in the water and grow out of control.

Research is ongoing to better understand what's been happening, Stumpf said. It could help fine-tune future forecasts. But climate change is definitely a factor in the mix.

"We know that climate is changing. We know that this is happening in states here in the Great Lakes region," Corson said. Changes in Ohio include a trend toward warmer average temperatures and more intense rainfall that usually increases stormwater runoff.

When soil can't absorb that runoff, it carries nutrients from fertilizers into waterways, along with other pollution. Fertilizer runoff from farms is a major source of both phosphorus and nitrogen, although some amounts also come from places like golf courses and suburban subdivisions.

Researchers are seeing shifts in algal bloom patterns elsewhere in the United States. But "changes are really specific to the individual area where you are," Corson said. Many coastal areas are experiencing warming trends and changes in precipitation patterns, along with shifts in land use that increase the amount of impervious surfaces. "Those are all occurring, and the shapes of the blooms are changing as well," he said.

The Outlook This Summer

The severity of Lake Erie's algal blooms varies from year to year. Factors include the levels of nutrient loading from the Maumee River basin, which covers a large part of northwestern Ohio, along with smaller areas in Indiana and Michigan.

The basin accounts for nearly half of the total phosphorus going into Lake Erie's western basin each year, according to Laura Johnson, who heads the National Center for Water Quality Research. She and others are especially interested in the amount of bioavailable phosphorus reaching the lake's western basin each year. Bioavailable means the phosphorus is in a form algae can use.

Estimates for that loading each spring come from flow data and chemical analyses of samples pulled at stream monitoring equipment in Waterville, which accounts for roughly 96 percent of the watershed. More than 60 percent of the area's total bioavailable phosphorus loading from March 1 through June 23 happened in April, Johnson said.

That month was the wettest on record for the region, and more rainfall generally means more fertilizer runoff. However, it was also a mild winter. Relatively dry soils could absorb a fair amount of the runoff, which prevented "crazy flash floods," Johnson said. Some phosphorus remains in the lake from prior years' discharges.

Stumpf and his team fed information from Johnson's group and other data into three models to estimate how severe this year's algal bloom will be on a scale from 1 to 10. "Three models give you a better chance of bracketing the right result," Stumpf explained.

This year's work also reflects a tweak to account for the changing pattern of earlier starts and longer peaks for Lake Erie's algal blooms. "Now we're training those models on data from 2013 to 2023," Stumpf said. The more current data should improve the models' results.

For this year, NOAA predicted a Level 5 bloom, with a range of 4.5 to 6. Fortunately, Corson said, technology continues to improve ongoing monitoring of algal blooms. Water treatment plants' technology has improved as well, he noted.

"The bloom isn't all over the lake all the time," Stumpf stressed. Wind patterns and other factors determine which areas are affected at any particular time. Checking NOAA's updated forecasts can help for planning recreational activities.

"That's going to show you where the bloom is going," said Chris Winslow, director of Ohio Sea Grant and Ohio State University's Stone Laboratory. The Ohio Department of Health's BeachGuard webpage also reports sampling results for cyanobacteria toxins and E. coli bacteria.

Researchers also advise common sense. If the water appears green and scummy, "keep yourself, your kids and your pets out of the water," Stumpf said. Not all algal blooms have high levels of the toxin-producing strains, but it's not worth taking chances.


Kathiann Kowalski wrote this article for Inside Climate News.


get more stories like this via email

The fight against the effects of climate change in Illinois has more help.

Under the Biden Administration's pollution reduction plan, the U.S. Environmental Protection Agency will distribute $430 million to reduce greenhouse gas emissions. The Climate Pollution Reduction Grant will also accelerate clean energy and promote workforce training.

Angela Xu, municipal engagement manager for the Illinois Environmental Council, said the grant is another step forward in Illinois' clean energy progress.

"We have really seen significant progress on our climate and equity goals due to the passage of the Climate and Equitable Jobs Act -- or CEJA -- in 2021," Xu pointed out. "We're seeing a lot of possible federal funding from the Inflation Reduction Act. It helps us double down on the great progress that we're seeing and secure a more equitable, affordable, and healthy future for all Illinoisans."

Xu said the grant supports projects like building and industry, decarbonization, freight, electrification, climate-smart agriculture and renewable energy. A total of $4 billion in federal funds was distributed to 25 state, local, and tribal entities. A comprehensive climate action plan must be submitted by all grant recipients to the federal government in 2026.

According to the Chicago Metropolitan Agency for Planning, roughly two-thirds of the northeastern Illinois region's emissions come from buildings, in the form of electricity or natural gas for heating and cooking. The funding supports the switch to electric appliances, heating and cooling, building equipment and more.

Xu noted other areas also stand to benefit from the grant.

"The funding enhances the workforce development programs already established by CEJA," Xu explained. "The Climate and Equitable Jobs Act and the federal Inflation Reduction Act are working together to bring historic climate investments home to our communities, with particular attention to low-income and disadvantaged communities across the state who need clean air affordable, energy and clean energy jobs the most"

Roughly $172 million will be allocated to decarbonize Illinois' buildings, which currently comprise nearly 70% of Chicago's carbon footprint. Another $115 million is budgeted for electrifying Illinois' transportation sector to boost infrastructure and ramp up acquiring electric freight vehicles, and more than $3 million is designated for a freight hub data collection and analysis program.

Ohio is becoming a focal point in the fight against climate change, thanks in part to its industrial might and a growing interest in carbon capture technology.

As the state looks to balance its economic needs with environmental responsibility, carbon capture utilization and storage is emerging as a critical tool. Critics of carbon capture voice concerns it could prolong the use of fossil fuels.

Simone Stewart, senior industrial policy specialist for the Climate and Energy program at the National Wildlife Federation, said in industrial states like Ohio, the technology will be important to curb the effects of carbon emissions.

"There's a big industrial component to their economies but at the same time, we want to act on climate action and address the climate crisis," Stewart pointed out. "We can't continue to emit CO2, so this allows us an alternative pathway."

Ohio's heavy industries, especially in manufacturing and raw materials, are both a strength and a challenge. Stewart acknowledged the sectors are hard to decarbonize, due to the emissions generated in the production processes. However, carbon capture utilization and storage provides a way to reduce the environmental impact while maintaining industrial productivity.

Stewart noted carbon capture is more than an industrial solution, it is also about protecting wildlife and preserving natural habitats, a connection of which she stressed the National Wildlife Federation is keenly aware. She stressed the importance of considering the ecological impact of industrial activities.

"While preserving the economy, while thinking about how infrastructural buildout is going to affect conservation and affect ecology, it really became important to us -- as a federation, and specifically as a climate team -- to participate in these conversations," Stewart added.

The privately owned energy company Tenaska is building a Tri-State Carbon Capture and Storage Hub to serve industrial customers in Ohio, Pennsylvania and West Virginia.

New York and the nation have seen sweeping impacts since the Inflation Reduction Act's passage two years ago. New York received $34 billion from the IRA for large-scale clean energy generation and storage. Along with funds to expand the state's clean energy sources, it's also provided resources for homeowners to make their homes climate efficient.

Actress Yetide Badaki says the law's passage creates an equitable climate future.

"To achieve equality, we must solve and work for environmental justice for all. The Inflation Reduction Act's focus on environmental justice and justice for the areas is historic and it puts us on that path," Badaki said.

Environmental justice communities have been a priority across New York State as storm damage worsens. This year, the state has seen an estimated $23 billion in damage from 'billion-dollar disasters'. Though New York City is a concentrated hub of E.J. communities, they can be found across the state. IRA funds are being provided for homeowners across the state to prepare their homes for blustering storm impacts.

Many elected officials see the Inflation Reduction Act as a way to make the U.S. energy independent. Creating energy through wind, solar, and other renewable means reduced dependence on other countries for national energy needs.

Alex Cornell du Houx, president of Elected Officials to Protect America, said this benefits national and global security.

"The U.S. produces a decent amount of oil and gas, but it can never supply the world, and this infrastructure is extremely vulnerable, as we've seen in Ukraine. So, to make sure that we're energy secure we've got to be able to move away from oil and gas. It's as simple as that," he said.

He added the IRA's clean energy funds can reduce the influence of groups like the Organization of the Petroleum Exporting Countries or OPEC. The Russia-Ukraine War has made energy independence a rising concern. The World Population Review finds the U.S. imported 405,000 barrels of oil from Russia in December 2021.