'Shrinking glaciers could disrupt marine ecosystems': Study
A new 2025 study from UC San Diego shows that as glaciers melt and retreat, they're sending less iron and manganese—key nutrients for plankton—into the ocean.
Since plankton are at the heart of marine food webs, this drop in nutrients could ripple through entire ecosystems.
How stable and retreating glaciers differ
Researchers compared Alaska's fast-retreating Northwestern Glacier (which has shrunk nearly 15km since 1950) with nearby stable Aialik Glacier.
Meltwater from the retreating glacier had noticeably less bioavailable iron and manganese than its stable neighbor.
Even though both glaciers are made of similar rock, shrinking ones deliver fewer useful nutrients to the sea.
Implications for other glacier regions
The findings suggest that places like the Himalayas and India—where glaciers are also melting fast—could potentially see similar drops in nutrient-rich meltwater, if the same processes occur there.
That means river life, fisheries, and even local economies might feel the impact as ice loss speeds up worldwide.
The takeaway: keeping an eye on both glacier retreat and water chemistry is more important than ever.