A new study from Umeå University, published in PNAS, reveals that ice can actively break down iron minerals—more effectively than liquid water. Researchers found that ice at –10°C released more iron than water at +4°C, challenging the belief that cold slows chemical reactions.
Using advanced microscopy, they studied goethite (a common iron oxide) and organic acids, showing that freeze-thaw cycles and salinity influence iron release. Fresh and brackish water boost dissolution, while seawater suppresses it.
These reactions are especially relevant in acidic frozen environments like mine drainage sites and Arctic soils.
