Study shows Greenland's ice sheets will continue to shrink even if global warming stops

Researchers from Ohio State University have concluded a new study that shows that glaciers on Greenland have shrunk so much that even if global warming stopped today, the sheet would continue to shrink. The study results show that the glaciers have passed a tipping point where snowfall replenishing the sheet each year can't keep up with ice that is flowing into the ocean.

Researcher Michaela King says that the study found that ice discharging in the ocean is far surpassing snow that's accumulating on the surface of the sheet. The study involved analyzing monthly satellite data for more than 200 large glaciers that are draining into the ocean around Greenland. The data shows how much ice is breaking or melting from the glaciers into the ocean and the amount of snowfall each year.

Snowfall is the method through which the glaciers are replenished. The team discovered that throughout the 1980s and 90s, snow gained through accumulation and ice melted from glaciers were mostly in balance resulting in the eye sheet remaining intact. In those decades, Greenland's ice sheets generally lost about 450 Gt (gigatons) of ice each year, which was replaced by snowfall.

The amount of ice lost each year began to increase steadily around the year 2000 to the point that the glaciers are losing approximately 500 Gt each year. While the ice loss increased, snowfall did not. Over the last decade, the rate of ice loss from the glaciers has stayed about the same. According to the team, the ice sheet will gain mass in the current climate in only one out of every 100 years.

King says that the large glaciers across Greenland have retreated by about 3 km on average since 1985. The study shows that even if climate change stopped ice lost from glaciers draining into the ocean would still exceed ice gained from snow, and the glacier would continue to shrink for some time.