Human contribution to global loss of glacier mass had shown a steady increase between 1991 and 2010, a new study published in Science journal says. From a quarter of the loss in glacial mass between 1851 and 2010, human contribution to the loss rose to nearly 70% between 1991 and 2010. A team of scientists headed by Ben Marzeion from the University of Innsbruck said they had found “unambiguous evidence” for anthropogenic glacier mass loss in recent decades. Glaciers and ice caps provide among the most visible indications of the effects of climate change, according to the inter-governmental panel on climate change. Melting glaciers are an icon of anthropogenic climate change, say the authors of the study, but glacier responses usually take decades or longer. Hence, the authors pointed out that the present-day glacier loss is a result of natural climate variability and “current anthropogenic forcing”. The scientists used computer simulations to simulate glacier changes between 1851 and 2010, running their models based on the Randolph Glacier Inventory. The climate researchers were able to distinguish between natural and human factors contributing to climate change in their model as they could include different factors contributing to glacier loss. “While we keep factors such as solar variability and volcanic eruptions unchanged, we are able to modify land use changes and greenhouse gas emissions in our models,” Marzeion said in a media statement. In the 19th and first half of the 20th century, the team observed that glacier mass loss attributable to human activity was hardly noticeable but since then has steadily increased, according to Marzeion.