Conference focuses on effects of climate change
August 11, 2016
by Diana Zimmerman
On June 17 at the Vancouver Hilton in Vancouver, the 2016 Science to Policy Summit sponsored by the Lower Columbia Estuary Partnership, scientists and policy makers talked about climate change and how it could affect the lower Columbia River.
“It’s not that it's changing,” Jan Newton, the Senior Principal Oceanographer for the University of Washington Applied Physics Laboratory said. “Things are always going to change. It’s that the rate of change is rapid and to some extent, unprecedented. The rate of acidification is nearly 10 times faster than any period over the last 50 million years.”
Catherine Corbett, the chief scientist and director for technical programs for the Estuary Partnership gave an overview of what she and her colleagues were concerned about when it came to the lower Columbia.
• impacts of sea level rise on the lower Columbia;
• loss of wetlands and habitat in the flood plain;
• more intense storms and increased wave energy;
• increased erosion;
• changing patterns in upwelling;
• ocean acidification and hypoxia entering the Columbia more frequently and further up with sea level rise;
• warming temperatures in the main stem which would increase droughts;
• possible shifts in what is considered native species, and
• changing precipitation patterns, with more falling as rain than as snow creating less snowpack.
According to Corbett there were three strategies to mitigate for the impacts of climate change.
• Try to predict what is going to be inundated and changed by changing water runs cause by flooding in order to protect future wetlands and infrastructure.
• Locate, restore and protect cold water refuges to help cold water acclimated species like salmon and steelhead.
• Discuss habitat and large fauna shifts.
According to Corbett, two long term monitoring stations are showing that the lower Columbia functions similarly to a lake.
The main stem has been warming for decades, Corbett said.
“It’s going to continue to warm up. When the water reaches 19 degrees Celsius it starts to stress some of the fish. It’s been 19 degrees Celsius every August for many years and scientists are starting to see it reach those temperatures in July and into September. There is little we can do to change the main stem temps because the tributaries do little to influence it but we can locate, restore and protect cold water pockets.”
According to Newton, they know climate change is happening because of the data time series.
“Data informs knowledge,” she said, “knowledge informs power, especially in a changing environment.
Scientists have documented an increase of CO2 not only in the atmosphere, but in the ocean, according to Newton. Increased CO2 reduces the pH of the ocean, leading to acidification.
Newton is quick to point out that there is a difference between acidic and acidified.
Ocean acidification is a global scale event, she said, and it’s due to fossil fuel burning and cutting down photosynthesizers which cut CO2.
“Are we increasing that rate at a rate where some of the species that we care about can’t keep up?” she asked. “That’s the scary bit.”
Oysters and other organisms like terrapods, a food source for salmon, rely on certain levels of pH to make their shells. They will be affected.
“When you don’t have as much carbonate dissolved in the sea water,” Newton said, “they have to expend more energy to get it. It’s harder and they are littler with an increase in the chances of deformities.”
Fewer shellfish will in turn affect water quality.
Higher CO2 will make harmful algal blooms more toxic. They’ll grow faster.
Not every species will be affected. Jellyfish and worms will still thrive. According to Newton, some species may be able to adapt.
“The Columbia River Estuary is fed by the low pH, low aragonite saturation in state waters of the Columbia River,” Newton said, “but it is also influenced by the upwelled oceanic water that has low pH, low aragonite and low oxygen. Some people would call this a double whammy.”
“How will climate change influence this situation?” she said. “People are calling the blob a marine heat wave. As climate change occurs, we have heat waves and now they are becoming more common. The idea is that the marine heat waves will also become more common. And how far will oceanic intrusion penetrate with sea levels rising?”
Lara Whitely Binder, the Senior Strategist for the University of Washington Climate Impacts Group spoke for a while about rain dominant systems and snow dominant systems and how they affect rivers.
She expects there to be an increase in temperature and precipitation with drier summers and wetter winters. Heat waves will be hotter and longer in duration. There will be heavy rain events with more flooding over longer durations and a significant loss in snow pack.
Snow dominant systems like the Columbia River will change to a rain dominant system. It will affect the timing of runoff and reduce the generating capacity in the summer for hydroelectric.
“People talk a lot about the uncertainties around climate change,” Binder said. “I would gladly take the uncertainties of climate change over the uncertainties of human responses to climate change. It’s easier to predict the climate system than it is to predict the human system.”