A recent study conducted by Dr. Andrew Fountain, a Portland State geology professor, shows that global climate change has affected local glaciers. According to the study, Mount Adams, located 31 miles from Mount St. Helens in the Southeast Washington Cascade Range, is experiencing severe changes due to the warming of the planet.
A recent study conducted by Dr. Andrew Fountain, a Portland State geology professor, shows that global climate change has affected local glaciers. According to the study, Mount Adams, located 31 miles from Mount St. Helens in the Southeast Washington Cascade Range, is experiencing severe changes due to the warming of the planet.
Fountain found that in the period between 1904 and 2006, Mount Adams lost nearly half of its glacial mass, a significant increase over glacier loss in other parts of the Cascade Range. The study, completed in 2010, said that the “total glacial area decreased by 49 percent.”
“This was unexpectedly large because Rainier’s loss is 24 percent and Hood’s is 32 percent,” Fountain said.
The study cites recent changes in temperature as a potential factor in the loss of glacial mass. Summer air temperature has increased by approximately 1.5 degrees Celsius, and higher temperatures can reverse growth in the glaciers that was stimulated by winter precipitation.
“The main driver of glacier recession appears to be summer air temperature, as little change in precipitation has occurred over the past century,” the study states.
For Dr. Robert Scheller, assistant professor of environmental sciences and management at PSU, this is a significant indicator that climate change is real.
“Climate change isn’t some abstract thing that happens to people in Bangladesh,” said Scheller.
The loss of glacial mass is more than just an indicator of climate change. It could have serious geological and ecological effects on the areas surrounding Mount Adams. According to Fountain, some of these effects are already observable, especially with regard to erosion concerns.
“Glaciers erode their bed and transport the rock to the glacier margin called a moraine. Once the glacier retreats the moraines are over-steepened because the glacier is no longer there to buttress the moraine and they are susceptible to failure causing debris flows,” Fountain said.
Fountain cited 2006 flows that caused damages to roads in Government Camp, Hood River, Mount Hood Meadows Ski Area and Mount Rainier National Park.
“In November 2006, a heavy rain storm caused the collapse of numerous moraines around Hood and Rainier, resulting in debris flows. One of these flows crossed OR-35 cutting the roadway between Mount Hood Meadows Ski Area and Government Camp and the town of Hood River. Some roads in Mount Rainier National Park were closed for two years because of the same thing,” Fountain said.
Kendra Williams from the Oregon Department of Geology & Mineral Industries and program chair of the Willamette Rotaract said, “A debris flow is a type of landslide. What distinguishes debris flows are that they are constricted in a channelized area and they involve a saturated mix of rock, sediment and organic material.
“Debris flows can be very dangerous; they move extremely fast and are very devastating. They pose a threat to infrastructure in their way and human life when homes are built in debris flow hazard areas,” Williams said.
Williams found that through her research, the link between glacier loss and debris flows is not specifically correlated. Her study showed that “percent glacial coverage is directly proportional to debris flow occurrence and average annual rainfall is inversely proportional to debris flow occurrence.”
Williams said her findings were based on examinations of drainages and glacial mass. “I found that drainages with a higher percent glacial coverage were more likely to have debris flows. These things seem to contradict each other, but in reality the situation is just very complicated.”
“Drainages with a high percent glacial coverage most likely had debris flows because glaciers act as an impermeable surface funneling extra water into that drainage. The added water, which entered the drainage in a short period of time in November of 2006, caused slope failures and resulted in a debris flow,” Williams said.
According to Williams, the loss of glacial mass is the lesser concern with regard to erosion, but that the connection of glacial diminishment to climate change can have adverse effects.
“So the amount of rainfall entering drainage and what it falls onto—rock, ice and unconsolidated material—is really more important in the occurrence of a debris flow than the glacial loss. But glacial loss, in connection with climate change will most likely result in less snowfall and more rain,” Williams concluded.
The changes caused by the loss of glaciers in the Mount Adams area could be permanent. Although there are ways to reduce carbon emissions, some problems still trouble Fountain.
“We can reduce CO2, cool summer and winter temperatures. That’s the easy thing,” said Fountain. “The harder thing would be to increase winter precipitation. I don’t know how to do that.”
Lack of glaciers can also affect the climate resilience of an area or the ability of an area to recover from natural disasters such as fires. “In a nutshell, [the correlation] is between managed systems and how resilient they are,” said Scheller, who has examined case studies of areas similar to that of Mount Adams.
Currently, Fountain is continuing his research of glaciers in Antarctica, examining the state of the glaciers in that zone.
“We are monitoring glacier change in the McMurdo Dry Valleys, a polar desert of sandy gravel surrounded by glaciers. The glaciers in this region of Antarctica, unlike on the Antarctic Peninsula, are in equilibrium.”
Fountain noted that Antarctic glaciers are also facing trouble. “Our measurements are showing an increasing negative trend, meaning the glaciers are beginning to lose mass. We’re not sure at this time whether this is the beginning of a long term trend or just a temporary period of low snow winters and high melt summers.”
