|About 10 percent of the Earth’s land area is covered with glacial ice, which includes ice caps, glaciers, and ice sheets / Photo by: NejroN via 123RF|
About 10 percent of the Earth’s land area is covered with glacial ice, which includes ice caps, glaciers, and ice sheets. They are thickened ice masses made up of fallen snow that was formed over many years. But, no thanks to the current climate crisis, the Earth’s glaciers are melting away.
A recent study reported that our planet is losing up to 390 billion tons of ice and snow every year. Lead author of the study Michael Zemp from the University of Zurich stated that almost all regions where glaciers exist are losing mass for the past 30 years. Since 1961, the world has already lost 10.6 trillion tons of ice and snow mainly due to man-made climate change. The burning of fossil fuels has been releasing greenhouse gases such as carbon dioxide and methane into the atmosphere. As a result, the global temperature is increasing.
Aside from glaciers, glacier-fed rivers are also in danger.
Glacier-Fed Rivers are Disappearing
Glacier-fed rivers or glacial rivers are those that flow from the margin of a glacier. They are usually extremely affected by the large supply of sediment that arrives at the glacier terminus and the highly seasonal water supply from the glacier. These rivers have served as testing grounds for scientists to examine ecological concepts. However, there’s a high chance that these bodies of water will also disappear in due time.
The 2018 State of the Mountains Report conducted by researchers from the University of Alberta revealed the extent of the impact of the melting glaciers in Canada. For instance, a “Piracy Event” occurred in the Slims River, southwestern Yukon, causing the river to dry up. This is after the Kaskawulsh Glacier receded so much that its dwindling meltwaters started to flow in a completely different direction.
|Glacier-fed rivers or glacial rivers are those that flow from the margin of a glacier / Photo by: Leonid Tit via 123RF|
Joerg Schaefer of Columbia University’s Lamont-Doherty Earth Observatory stated that mountain glaciers are vanishing way, way faster than it was at the end of the ice age. “What we have seen over the last 150 years, all over the planet, is that these mountain glaciers record a retreat corresponding to 1 degree Celsius to 1.5 degrees Celsius warming over 150 years, with the biggest part of that retreat happening over the last decade,” he said.
According to Truthout.org, a non-profit, subscriber-supported news website devoted to the principles of equality, democracy, human rights, accountability, and social justice, there’s a great danger when glacier-fed rivers disappear as more than one-sixth of the entire global population will be at risk. Scientists expressed their concern not only with the worsening trend of glacial loss but also the impacts on fundamental water sources for ecological systems and humans alike.
Glacier-Fed Rivers Help in Draining Supraglacial Lakes
In 2016, scientists confirmed that thousands of pristine blue lakes have appeared on the ice sheets of East Antarctica. But this is not something to be celebrated about. Science Alert, a leading scientific publisher dedicated to publishing peer-reviewed significant research work, reported that a team of UK researchers analyzed hundreds of satellite images and meteorological data taken of the Langhozvde Glacier in East Antarctica.
The researchers discovered that between 2011 and 2014, Greenland had lost a massive 1 trillion tons of the ice sheet. The findings of the study suggested that the nearly 8,000 supraglacial lakes are the reason behind this. These lakes appeared to have been draining the ice sheets that led to the instability of the entire ice shelf. While they don’t last long because they either drain vertically through the floating ice, disappear through refreezing or overflowing into rivers on the surface that drains into the ice below, they remained harmful.
However, glacier-fed rivers have the potential to address this problem. Alison Banwell, a glaciologist at the University of Colorado Boulder, and her colleagues conducted a study to know why ice sheets in Greenland’s supraglacial lakes are not disappearing at a faster rate. According to Eos, a leading source for trustworthy news and perspectives about the Earth and space sciences and their impact, the researchers used the data from Landsat 8 satellite from 2014 to 2016.
The study revealed that the Blue River, a glacier-fed river in Petermann, has been slowly releasing pressure on the ice shelf and minimizing its flexure. This serves as a harmless export mechanism for supraglacial lake water. While this glacial river is rare, the researchers found out that the Blue River is a recurring feature of the Petermann glacier. This means that it is evidently reforming each summer after the winter snowfall.
Glacial Rivers Do Better in Absorbing CO2
Glacial rivers also play a vital role in mitigating the impacts of greenhouse gas emissions. Previous studies showed that although temperate rivers are home to thousands of species and help in nature conservation, they emit a far greater amount of carbon dioxide into the atmosphere than what they absorb. This means that they are contributing to the worsening climate change.
But glacial rivers are different. Since they are not very hospitable to aquatic life, they contribute fewer carbon gases. Aside from that, a recent study published in the Proceedings of the National Academy of Sciences discovered that these rivers have been secretly absorbing carbon dioxide from the atmosphere at a rate faster than the Amazon rainforest. According to The Guardian, a British daily newspaper, this occurs through a geological process known as chemical weathering.
Chemical weathering happens when particles are mixed within the water. The mixing together creates reactions since the water contains gases including carbon dioxide. The researchers found out that this leads to carbon dioxide being removed from the atmosphere as far away as 26 miles (42 kilometers) from the headwaters of the river. This is extremely impressive because glacial rivers can absorb CO2 40 times more compared to the Amazon rainforest.
“On a per-meter-squared basis, these rivers can consume a phenomenal amount of carbon dioxide,” Dr. Kyra St. Pierre, a biologist at the University of British Columbia and lead researcher on the project, said.
This means that glacial rivers can massively contribute to mitigating the impacts of the climate crisis. They also play an integral role in decreasing global temperature and other environmental issues. Thus, it’s important that while we are deeply concerned with glaciers, glacial rivers should also be prioritized.
|Glacial rivers also play a vital role in mitigating the impacts of greenhouse gas emissions / Photo by: VASILIS VERVERIDIS via 123RF|