Cryosphere decline exceeds safe planetary limits: study-Xinhua - 新华网

MELBOURNE, Nov. 13 (Xinhua) -- The degradation of Earth's frozen areas has exceeded safe planetary limits, posing growing long-term risks to ecosystems and human societies, new research has found.

The study, published in Science, examines four main indicators of cryosphere health: sea ice, snow area cover, permafrost and land ice. The latter, almost 90 percent of which is found in Antarctica, is on its way to departing the "safe" conditions in which human civilization developed, while the other three have already passed this threshold, according to a statement released Friday by Australia's Monash University.

The cryosphere, which includes ice sheets, mountain glaciers, sea ice, permafrost and snow cover, plays an irreplaceable role in regulating Earth's energy, water, carbon, methane cycles, and carbon storage capabilities, according to the study.

Their breakdown puts communities, ecosystems, and valuable freshwater resources at risk by accelerating global temperatures, sea level rise, ecosystem degradation, and the likelihood of catastrophic flooding and drought events, the researchers said.

The study concludes that the degradation of frozen landscapes is driven predominantly by human-induced climate change, in addition to regional human disturbances including black carbon emissions and industrial and infrastructure expansion. ■