March 31, 2017
“The Earth is sick and probably getting sicker.”
That ominous warning came from Dr. John P. Smol, a professor and the Canada Research Chair in Environmental Change at Queens University in Ontario, during one of his several presentations for ASU’s 2017 WTMA Distinguished Lectureship in Science.
Considered one of the world’s leading authorities on climate change, Smol also founded the Paleoecological Environmental Assessment and Research Lab (PEARL) at Queens University. He and his PEARL colleagues have conducted paleolimnology research on all seven continents, studying the physical, chemical and biological information stored in lake sediments to track environmental and ecological changes over years, centuries and beyond.
“Lake sediments are a history book or memory of the lake and the ecosystem around it,” Smol said. “All day every day, mud is slowly accumulating at the bottom of lakes. In that mud is a remarkably clear record of what happened within and outside the lakes.”
In his first public lecture, Smol detailed how he and his team collect and section core samples of lake sediments, date the sections using a uranium isotope, distinguish the physical and chemical fossils, and then analyze the data to track the history of a lake. He then showed how they used those methods to illustrate how recent climate warming is affecting Arctic lakes and ponds in far northern Canada.
“I focus on the Arctic because climate change in the Arctic shows the biggest changes and the earliest changes,” Smol said. “What happens in the Arctic is a harbinger of what is going to happen farther south and will affect all of us soon.”
“We often refer to those changes in the Arctic as ‘canaries in the coal mine,’” he added. “They are like those early smoke detectors miners used to detect gasses in the mines. The Arctic is the first to show environmental changes.”
Smol’s research showed that Arctic ponds are drying up faster than predicted because of warmer temperatures and subsequent increased evaporation, which has led to lower water levels, higher salinity and disappearing wetlands.
“Everyone is dependent on the environment, and we aren’t really treating it all that well,” Smol said. “Climate warming is the great threat multiplier. Nature is also very slow to forgive our mistakes.”
“We have to start taking control of our environment, if not for ourselves, then for our children and grandchildren.”
For his second public presentation, Smol concentrated more on how humans have become the dominant geological force on Earth, causing dramatic changes to the land, water and atmosphere through the spread of various contaminants, including pesticides, fossil fuels and heavy metals.
Again the Arctic was his beginning focal point as he showed how contaminants from all over the world are becoming concentrated there and in the Antarctic through what is colloquially known as “the grasshopper effect.”
“Contaminants hop across the planet from warm areas to cold areas,” Smol said. “Pesticides and other organic contaminants vaporize in warm temperatures and go up into the atmosphere. Then they condense in the colder atmosphere and come back down in precipitation. Where they land then warms up, and the cycle repeats so the contaminants move farther. They eventually get to cold regions that become like ‘sinks,’ and they don’t move anymore.”
Contaminants are also being spread through ocean currents and lake discharge, as well as through Arctic-nesting seabirds, causing various ecological problems that are affecting every part of the environment. And, since birds are basically a global distribution system, these issues will not be confined to the Polar Regions.
“Just in my lifetime, we have crossed serious ecological thresholds,” Smol said. “We may think the Arctic is far away and it’s not our problem, but we only have one Earth and I think it’s time we started dealing with some of these issues. We have to start taking control of our environment, if not for ourselves, then for our children and grandchildren.”
“Now is not the time for crippling pessimism or delusional optimism,” he added. “I think it’s time for clear and constructive thinking on how we can best deal with these problems. As scientists, we owe nothing less to our students, our colleagues and the public at large.”
(While on campus, Smol also offered research advice to ASU science faculty at an informal dinner.)