Man-Made Warming Becomes Main Cause of Glacier Retreat

Man-made greenhouse gas emissions have become the dominant cause of melting in glaciers from the Alps to the Andes that is raising world sea levels, a study said on Thursday.

Human emissions accounted for an estimated 69 percent of loss of ice from glaciers from 1991-2010, overtaking natural climate variations that had been the main driver of a retreat since the mid-19th century, researchers wrote in the journal Science.

Until now, scientists have struggled to quantify the impact of human behavior on glaciers because the frozen rivers of ice take decades, perhaps centuries, to respond to rising temperatures and shifts in snow and rainfall.

The study published on Thursday used historical observations of glaciers around the world, except in Antarctica, twinned with computer models to simulate all factors that could explain the retreat.  It found that natural variations were not enough on their own, meaning man-made greenhouse gases played an increasing role.

Man-Made Warming Becomes Main Cause of Glacier Retreat, Study Says