Ice glaciers have been melting rapidly since the onset of climate change. Now, a new research study shows that human activity is definitely to blame for at least 25 percent of the loss of ice in the region from 1851 to 2010. From 1991 to 2010, human activity is responsible for melting almost 66 percent of the glacier mass.
Studies portray the negative effects of glacial melting on the global climate and weather patterns. Another study released this week shows that extreme-weather conditions are worsened by the melting polar ice, as heat-carrying air waves that once were propelled by the temperature difference between the Arctic region and the Northern continents now become stalled for weeks or months, causing heat waves.
The melting polar ice caps have become very much associated with man-caused climate change, but until now there was no real evidence that humans had caused the ice caps to melt. Glaciers also respond to natural changes in climate, like solar changes. However, the glaciers have been melting too fast in the past two decades for it to be a natural change.
"Typically, it takes glaciers decades or centuries to adjust to climate changes," says climate researcher Ben Marzeion from the Institute of Meteorology and Geophysics of the University of Innsbruck.
The team, led by Marzeion, used computer simulations to study glaciers from 1851 to 2010.
"The results of our models are consistent with observed glacier mass balances," says Marzeion. The team studied not just glaciers in the Arctic region, but ones all over the globe, excepting those in Antarctica. They used the new Randolph Glacier Inventory (RGI), a database containing every glacier in the world, to perform the study.
"The RGI provides data of nearly all glaciers on the Earth in machine-readable format," says Graham Cogley, one of the people in charge of the RGI. He was also a co-author on the study.
The team used simulations of the glaciers with known factors, like solar variability and volcanic eruptions, steady. They added greenhouse gas emissions into the equation, and the way that land use has changed over the years. Their results were very conclusive, and showed that a significant portion of the glaciers had melted due to human activity.
"In our data we find unambiguous evidence of anthropogenic contribution to glacier mass loss," Marzeion says in the study.
The melting of the glaciers caused by human activity started out extremely small in the beginning of the Industrial Revolution, in the late 1800s and early 1900s, the study shows. That effect increased steadily until, during the last 25 years, human activity was responsible for melting a whopping 66 percent of the glaciers' mass.