This is the worry which haunts ice scientists delving into Earth´s threatened glaciers.
Deep inside them, the slumbering ice slabs hold information about Earth´s climate past, and pointers for the future.
The frozen archive is formed from compacted layers snow which fell hundreds, thousands or even hundreds of thousands of years ago.
Learning more about the past through examining the glaciers could help us predict how our planet will respond when global warming kicks into higher gear -- just decades from now, if predictions are right.
Only a tiny amount of this glacial material has ever been extracted and examined.
And as temperatures rise, the fringes of many glaciers are softening to mush, threatening the survival of this precious testament.
"We are the only scientific community working on climate history whose research material is disappearing," lamented Jerome Chappellaz at the Laboratory for Glaciology and the Geophysics of the Environment in Grenoble, southeastern France.
"It is time to do something -- we have to act now, while the glaciers are still a useable source."
That "something" is a new scheme to build a vault for ice cores extracted by scientists from the deep chill of Antarctica.
About 50-130 millimetres (two to five inches) wide, in sections between one to six metres (a yard to 20 feet) long, ice cores are glaciology´s mainstay.
Within them are telltale bubbles of gas, notably the greenhouse-gas carbon dioxide (CO2).
By studying them, "past eras can be reconstructed, showing how and why climate changed, and how it might change in the future," says the US National Snow and Ice Data Center.