FAIRBANKS - Hundreds of researchers are in Fairbanks this week to talk permafrost.
The Ninth International Conference on Permafrost started Sunday at the University of Alaska Fairbanks.
The conference is held every five years and attracted 600 participants from more than two dozen countries.
The participants will spend the next few days sharing research about permafrost, defined as ground that stays frozen for more than two years.
About 80 percent of Alaska is covered in permafrost.
Global warming could cause much of it to melt in the coming decades, causing billions of dollars in damage to roads, buildings and other infrastructure.