August 31, 2018 — From collecting field samples inside the ocean’s frozen ice pack to analyzing satellite images in the comfort of his Stanford office, Kevin Arrigo has been trying to figure out how the world’s rapidly thinning ice impacts polar food chains. Arrigo, a professor of Earth system science at Stanford School of Earth, Energy & Environmental Sciences, found that while melting ice threatens to amplify environmental issues globally, ice sheet retreat can provide much-needed food in local ecosystems.

Through this work, Arrigo discovered that thinning ice at the poles can alleviate polar food deserts by extending phytoplankton blooms. However, the silver lining associated with melting ice cannot make up for imminent threats, such as rising sea levels, associated with unchecked glacial shrinkage.

Arrigo, who is also the Donald and Donald M. Steel Professor in Earth Sciences, spoke with Stanford Report about his work on polar phytoplankton blooms and discussed whether recent news about sea ice breaking up suggests we’ve reached a tipping point.

What have you learned about how glacial melt impacts food chains in the extreme environments of the poles?

It turns out that when glaciers form, they accumulate particles and dust that contain essential nutrients like iron, on which all living things depend for survival. As glaciers melt, they add nutrients to the ocean and fertilize the local ecosystem. In Greenland and Antarctica, the ocean is short on iron, so melting glaciers make up for the lack of iron.

Read the full story at Stanford News