May 20, 2024
UC Irvine-led team uncovers ‘vigorous melting’ at Antarctica’s Thwaites Glacier
Satellite radar data show kilometer-scale seawater intrusion, causing ice to rise and fall

Irvine, Calif., May 20, 2024 — A team of glaciologists led by researchers at the University of California, Irvine used high-resolution satellite radar data to find evidence of the intrusion of warm, high-pressure seawater many kilometers beneath the grounded ice of West Antarctica’s Thwaites Glacier.

In a study published today in Proceedings of the National Academy of Sciences, the UC Irvine-led team said that widespread contact between ocean water and the glacier – a process that is replicated throughout Antarctica and in Greenland – causes “vigorous melting” and may require a reassessment of global sea level rise projections.

The glaciologists relied on data gathered from March to June of 2023 by Finland’s ICEYE commercial satellite mission. The ICEYE satellites form a “constellation” in polar orbit around the planet, using InSAR – interferometer synthetic aperture radar – to persistently monitor changes on the Earth’s surface. Many passes by a spacecraft over a small, defined area render smooth data results. In the case of this study, it showed the rise, fall and bending of Thwaites Glacier.

“These ICEYE data provided a long-time series of daily observations closely conforming to tidal cycles,” said lead author Eric Rignot, UC Irvine professor of Earth system science. “In the past, we had some sporadically available data, and with just those few observations it was hard to figure out what was happening. When we have a continuous time series and compare that with the tidal cycle, we see the seawater coming in at high tide and receding and sometimes going farther up underneath the glacier and getting trapped. Thanks to ICEYE, we’re beginning to witness this tidal dynamic for the first time.”

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