NEW DELHI — Rising temperatures in the Himalayas, home to most of the world’s tallest mountains, will melt at least one-third of the region’s glaciers by the end of the century even if the world’s most ambitious climate change targets are met, according to a report released Monday.

If those goals are not achieved, and global warming and greenhouse gas emissions continue at their current rates, the Himalayas could lose two-thirds of its glaciers by 2100, according to the report, the Hindu Kush Himalaya Assessment.

Under those more dire circumstances, the Himalayas could heat up by 8 degrees Fahrenheit (4.4 degrees Celsius) by century’s end, bringing radical disruptions to food and water supplies, and mass population displacement.

Glaciers in the Hindu Kush Himalayan Region, which spans over 2,000 miles of Asia, provide water resources to around a quarter of the world’s population.