Have you ever noticed a snow-covered street dimpled with little holes on the surface? Called cryoconite holes, they are small circles of black dust, soot, or dark microbes that form on blankets of snow. The dark patches absorb more sunlight than the nearby white snow, warming and melting holes beneath itself. These holes can be tiny unique ecosystems for arctic life. They may also impact glacier loss.

The glaciers of Kashmir are melting at frightening rates. A new study is the first to examine how that melt relates to cryoconite holes. Scientists examined Machoi glacier, a special region that has been photographed since 1875 due to its beauty. These historic photos combine with satellite imagery to reveal that the ice sheet has been receding for the last 100 years.

Scientists revealed that cryoconite holes lead to a loss of albedo, or reflection of sunlight. This then causes an increase in temperature at certain points that exacerbate glacier melting. The study also determined that that during the COVID-19 lockdowns, aerosol pollution levels drastically decreased on the glacier. Those same pollutants, when they land in snow, may act as sites where cryoconite holes begin to form, though the science of that process is still developing.  Thus, air pollution from traffic and industrial plants may increase cryoconite holes formation, which further melts our glaciers. The study urges future researchers to pay more attention to cryoconite holes and reveal their effects on glacier biogeochemistry.