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Last year, INSTAAR lost one of the people who helped shape the institute into what it is today. Former INSTAAR research librarian and polar climate data expert Martha Andrews passed away peacefully at her Boulder home with her husband, John Andrews, by her side.��

To honor Martha’s career, John established a new scholarship fund for graduate students working to understand and address climate change in polar and alpine regions. This summer, INSTAAR PhD candidate Trisia Tellez became the first recipient of the scholarship.��

Trisia Tellez poses for a photo on the Pacific coast. (courtesyTrisia Tellez)

Tellez’s summer project is ambitious. Using the scholarship funding, she secured samples from an ocean sediment core extracted from more than a mile beneath the South China Sea. Over the summer, Tellez will run chemical analyses of fossils preserved in the sediment. These analyses will produce a record of deep-sea temperatures stretching back a million years.

“What we have now are records of mean ocean temperature instead of deep-ocean temperature,” Tellez explained. “That doesn’t resolve all of the questions we have.”

Tellez will start the fifth and final year of her PhD program in INSTAAR fellow Tom Marchitto’s lab this fall. Though she is still early in her career, she has known what she wanted to do for a long time. Growing up in El Paso, Texas, she loved science classes and looked forward to the annual science fair.

“I decided that I was going to get a PhD in second grade,” Tellez said.

A love for nature and a growing concern about climate change eventually drew her to Earth science. In 2022, she graduated with a B.S. in environmental science from the University of Texas at El Paso, before coming to INSTAAR to join Marchitto’s lab.

Tellez’s work at INSTAAR has laid the theoretical foundation for her current project. She built on research from Marchitto and others showing how ocean conditions affect the chemical composition of foraminifera shells — tiny exoskeletons secreted by single-celled organisms that live on the seafloor.��

Through laboratory experiments, Tellez showed that the ratio of lithium to magnesium in these shells can tell us the temperature of the surrounding ocean when the shells formed. Now, she will extract fossils of a deep-sea-dwelling species from the sediment core. The chemistry of those fossils will provide precise estimates of past ocean temperatures for periods of interest spanning back a million years.

“I wanted to do a whole global ocean record, but Tom said ‘someone could spend a whole lifetime doing that,’” Tellez explained. “I’m just going to look at the coldest and warmest periods.”

The scholarship has expanded the scope of Tellez’s dissertation, allowing her to pursue a more ambitious research question. She is grateful to be able to spend the whole summer looking at fossils.

“This scholarship is the whole reason we were able to select a core, get the samples here, and have the time to process the samples,” she said. “I’m quite excited.”