Sea ice is a critical indicator of changes in the Earth’s climate. A new discovery by Brown University researchers, including , a doctoral student in Earth, Environmental and Planetary Sciences, could provide scientists a new way to reconstruct sea ice abundance and distribution information from the ancient past, which could aid in understanding human-induced climate change happening now. In a study published in , the researchers show that an organic molecule often found in high-latitude ocean sediments, known as tetra-unsaturated alkenone (C37:4), is produced by one or more previously unknown species of ice-dwelling algae. As sea ice concentration ebbs and flows, so do the algae associated with it, as well as the molecules they leave behind. Read more.