Stonebreen’s Beating Heart – NASA Science

Edgeøya, an island located in the southeastern part of the Svalbard archipelago, is defined by stark arctic expanses and rugged terrain. Yet even here, halfway between mainland Norway and the North Pole, life persists, from mosses to polar bears. The southern lobe of Stonebreen, a glacier that flows from the Edgeøyjøkulen ice cap to the Barents Sea, gives the landscape a different type of life. Its ice cream beats like a heart.

The apparent heartbeat comes from the fact that the ice speeds up and slows down with the seasons. This animation, based on satellite data collected between 2014 and 2022, shows how fast the glacier’s surface ice moves on average during each month. In winter and spring, the ice flows relatively slowly (pink); in late summer it runs toward the sea at speeds in places exceeding 1,200 meters per year (dark red). As of summer 2020, speeds reached 2,590 meters per year (23 feet per day).

Typically, summer accelerations are caused by meltwater seeping from the surface to the base of the glacier, where ice sits on top of rock, explained Chad Greene, a glaciologist at NASA’s Jet Propulsion Laboratory (JPL). “When the base of a glacier is flooded by meltwater, the water pressure at the base increases and allows the glacier to slide more easily,” he explained.

Data for the animation comes from the ITS_LIVE project, developed at JPL, which uses an algorithm to detect the speed of glaciers based on surface features visible in optical and radar satellite images. In 2025, Greene and his JPL colleague Alex Gardner used ITS_LIVE data to analyze the seasonal variability of hundreds of thousands of glaciers across the planet, including Stonebreen.

Stonebreen is a glacier in flood, a type that oscillates between stretches of relatively slow movement and sudden accelerations when the ice may flow several times faster than usual. These flare-ups can last from several months to several years. Globally, only about 1% of glaciers are surge-type, although they are relatively widespread on Svalbard.

Before 2023, Stonebreen spent several years advancing at high speed after melting along its front likely destabilized the glacier, according to Gardner. Even during this period of soaring, the ice followed a seasonal rhythm – accelerating in summer and slowing in winter – while continuing its faster overall flow toward the Barents Sea.

Since 2023, however, the glacier has virtually stopped, with only a short period in summer when meltwater causes Stonebreen to slide across the ground. It has entered a phase of calm, or “quiescence,” which is a normal part of the surge-type glacier cycle.

These heartbeat-like seasonal pulses and long-term variations in ice flow at Stonebreen and other glaciers around the world can be explored using the ITS_LIVE app.

Maps provided by Chad Greene and Alex Gardner, NASA/JPL, using data from the NASA MEaSUREs ITS_LIVE project. Story by Kathryn Hansen.

• Greene, CA and Gardner, AS (2025) Seasonal dynamics of Earth’s glaciers and ice sheets. Science390, 6776.
• NASA Earth Observatory (December 3, 2025) Satellites detect seasonal pulses in Earth’s glaciers. Accessed February 12, 2026.
• NASA Jet Propulsion Laboratory (2026) ITS_LIVE. Accessed February 12, 2026.
• Noël, B., et al. (2020) Low altitude of Svalbard glaciers leads to high variability in mass losses. Natural communications11(4597).
• Strozzi, T., et al. (2017) Frontal destabilization of Stonebreen, Edgeøya, Svalbard. The cryosphere11(1) 553-566.