12.5 trillion tons of polar ice vanished since 1970s, satellite data reveals

For nearly half a century, satellites have kept a silent, unflinching watch over Earth's polar regions, and the record they have assembled is one of the most consequential in the history of human knowledge: 12.5 trillion tons of ice, accumulated over centuries, has melted away since the 1970s. Greenland and Antarctica — the twin pillars of Earth's frozen architecture — are the sources of this loss, and their diminishment translates with mathematical certainty into rising seas that now threaten the inhabited edges of every continent. This is not a forecast of what may come; it is a measurement