A huge portion of the northern hemisphere will suffer from devastating water shortages because of global warming, a new study is claiming.

This massive portion of our planet is home to 2 billion people, and a team of U.S. and European scientists are claiming that it will suffer huge shortages in water by 2060 that could have devastating results for humanity, according to a Christian Science Monitor report.

Why? It’s because of the shrinking snowpack, which supplies close to a hundred water basins in the northern hemisphere.

Justin Mankin, who is the study’s lead author, said in a statement that water managers “may need to prepare for a world where the snow reservoir no longer exists.”

California has gotten an early taste of this future. They’ve been hammered by drought in recent years, and it’s largely due to the declining snowpack in the Sierra Nevadas.

If this study is to be believed, it’s only going to get worse for northern and central California, but it’s not just the western United States that is going to struggle. Basins in Portugal, Spain, and southern France will also be depleted, as will the Shatt al-Arab basin, a vital water resource for the Middle East that supplies Iraq and Syria.

The snowpack is important because it essentially acts as a seasonal supply of water when it melts and trickles down to lower elevations. With less of a snowpack, there’s less water coming to areas that need it.

World leaders will be meeting in Paris before the end of the year to propose some solid solutions to the global warming problem.