Within permafrost is ice: sometimes countless crystals ... the carbon currently in the atmosphere as CO2. Eighty-year-old black spruce, scrawny as pipe cleaners, grow on north-facing slopes ...

As permafrost laced with buried ice thaws ... has tracked abrupt thaw in a black spruce forest near Fairbanks for the past 15 years. Flooding there, she has found, is destabilizing tree roots ...

Standing dead black spruce trees in a burned area near Delta ... measure the depth-to-permafrost, and to make electronic measurements of soil moisture for NASA's ABoVE campaign.