Last December in Paris, in the middle of challenging climate change negotiations, small islands captured the attention of delegates and international media alike by refusing to budge on their long-time call for a n ambitious 1.5 degree Celsius target to be reflected in the final agreement.

Many veterans of the talks saw the call as a long shot at best, but in the end, it made it in and yesterday science provide more evidence of the wisdom of the island stance.

In a new paper, appearing in Atmospheric Chemistry and Physics, climate scientists argued that a 2 degree temperature goal was too high and could lead irrevocably to untenable impacts, including gargantuan storms and catastrophic sea level rise affecting all coastal cities around the world.

“We’re in danger of handing young people a situation that’s out of their control,” said James E. Hansen, the retired NASA climate scientist who led the research.

The paper upends the conventional view of climate science by suggesting severe impacts could be only decades—not centuries—away.

Drawing insights from abrupt climatic changes that took place in the geologic past, about 120,00 years ago, the study found that fresh water from melting land ice could trigger a feedback loop causing ice sheets in Greenland and Antarctica to c0llapse.

Such an event would interfere with circulation patterns that regulate global temperatures and weather, sending climatic stability into a spiral. More research must be done to affirm such a prediction, but clearly the 1.5 degree mark serves as an indispensable goal to steer policy decisions. Here as elsewhere, when it comes to carbon and global temperature rise, less is more.