Mild bloom forecast
’Berg water quality lab plays key role in algal prediction
GIBRALTAR ISLAND — This year’s harmful algal bloom on Lake Erie is expected to be of moderate severity — a 6 on a 10-point scale — according to research scientists who made the announcement Thursday.
Rick Stumpf, oceanographer for the National Oceanic and Atmospheric Administration’s National Centers for Coastal Ocean Science, made the prediction at a news conference at Ohio State University’s Stone Lab on Gibraltar Island, across the harbor from Put-in Bay.
The prediction compares to 2015’s record-setting 10.5-point bloom, the 10-point 2011 bloom and last year’s 8-point bloom.
“That’s putting it definitely below 2017,” he said. “Yes, it’s a significant bloom. Much smaller than we’ve seen last year but larger than ’16.”
Although Stumpf said the bloom can be affected by weather in the remainder of July, he said forecasts call for stable weather, which would not impact the bloom forecast.
“We’re not expecting heavy rainfall events,” he said. “We’re not expecting any significant change.”
The accuracy of the forecast depends on the use of several models to interpret data, Stumpf said.
“The fact that we have the combination is very important,” he said. “We’ve been correct in all years except maybe 2016.”
Reporting the location of blooms is assisted by the European Space Agency’s Sentinel-3A satellite, which collects data every other day, he said. The next generation — the Sentinel-3B satellite — is on the horizon.
“We’ll get an even better job of collecting forecast data,” he said.
Stumpf said this year’s bloom already has started, which is earlier than usual.
“The lake is warmer this year by about 7 degrees,” he said. “That does not mean we’re going to have a worse bloom this year. It just means it started early and timing may be a little earlier.”
The bloom is fueled by phosphorus, he said, and when the fuel supply is gone, the bloom will end.
“It’s the phosphorus,” he said. “That’s the key.”
Stumpf said the status of blooms and reporting their locations have improved over the years, and people who use Lake Erie for recreation can sign up to receive updates at www.glerl.noaa.gov.
“You can have a good time on Lake Erie,” he said. “I can’t emphasize that enough.”
Many variables cause blooms to change location and “green scum” on the water to come and go.
“Conditions vary greatly between years,” Stumpf said. Often, he said, wind mixes the water so no scum forms on the surface.
“If we have southerly winds, it becomes an Ontario problem,” he said. “If we have northerly winds, it becomes an Ohio problem.
“Most of the lake will be fine,” he said. “We have seven or eight thunderstorm days in Ohio each summer. But that doesn’t stop you from using the lake. It’s similar.”
“Please get the bulletin and look at it and use it,” he said.
In addition to the NOAA forecast, the news conference included background information and research updates about HABs.
Laura Johnson, director of Heidelberg University’s National Center for Water Quality Research, reviewed average rainfall for 1975-2017 and pointed out the amount of nutrient-laden discharge from the Maumee River. She said less rain has caused less nutrient runoff from farm fields, which means less dissolved reactive phosphorus entering rivers and ending up in Lake Erie.
“We’ve had seven high flows, but not all that crazy,” she said.
Compared to other years, she said the flow was average this year.
“We’re right in here between 2016 and 2017,” she said, pointing to a slide. “Not as high as 2014, 2008 and 2017 and those other scary years.”
Stumpf said the forecast depends on NCWQR data, and its long history of collecting water flow history from rivers.
“The key to all this is Heidelberg’s data,” he said. “I can’t emphasize that enough. It’s an extraordinary data set.”
For more information on HABs and to ask related questions, visit go.osu.edu/facts.