Greenland’s ice is melting faster than scientists had hoped, according to new research, placing the planet on track for the worst-case sea-level rise scenario predicted by climate projections.

The new analysis of 26 satellite measurements taken over the last three decades revealed a sevenfold increase in melt since 1992, the Guardian reports. In 1992, Greenland’s ice sheets lost an average of 33 billion tons a year. In the past decade, the average septupled to 254 billion tons of melt.

All told, 3.8 trillion tons of Greenland’s ice liquified and spilled into the world’s oceans, raising them 0.39 inches (one centimeter).

“Around the planet, just one centimeter of sea-level rise brings another 6 million people into seasonal, annual floods,” Andrew Shepherd, climate scientist and one of the lead authors of the study, told the Washington Post.

The findings of the international team of 89 scientists raise predictions of sea-level rise for the year 2100 by 2.7 inches to a total of 26.3 inches. This will place 400 million people at risk of costly, destructive flooding — up from the 360 million predicted by the Intergovernmental Panel on Climate Change (IPCC). The added inches of global sea-level rise places the planet on track with the IPCC’s most pessimistic predictions.

“What that means is that really, the midrange scenario becomes what was previously the upper scenario,” Shepherd told the Post. “They will have to invent a new upper scenario, because one currently doesn’t exist.”