Overview
- Two peer‑reviewed studies published Sept. 24–25, 2026 use global GNSS stations and gravity analyses to show a clear, measurable change in Earth’s shape driven by recent ice loss.
- Christos Kotsakis’s GNSS analysis finds polar uplift rates have roughly doubled since the late 1990s from about 0.5 mm per year to roughly 1.0 mm per year while equatorial regions sink, making the solid Earth slightly less flattened.
- Donald Argus and colleagues at NASA JPL recalculated the seasonal shift of Earth’s center of mass and report the annual fluctuation is about half the size of estimates made eight years ago, resolving earlier differences between measurement methods.
- Surface geometry and gravity respond differently because meltwater moves mass toward low latitudes; the solid surface grows rounder even as the planet’s gravity field becomes more flattened where ocean mass concentrates.
- Though changes are measured in millimetres per year, they add up over decades and can alter Earth’s rotation and affect precision systems such as GPS and international timekeeping, so scientists are now assessing those practical impacts.