How is the permafrost doing? Is there any global measurement? If you dug in 3 meters would it still be cold? What metric is useful at all here, I’ve never had

How is the permafrost doing? Is there any global measurement? If you dug in 3 meters would it still be cold? What metric is useful at all here, I’ve never had to consider it since the concept suggests permanently frozen, and that was a reliable assumption