← No. 014 TUE 13 OCT 2026

Northwest Greenland was ice‑free about 400,000 years ago.

Northwest Greenland — Camp Century, Greenland

Sediments found beneath the Camp Century ice core contain twigs, moss and insect parts—life you only get on open ground. Grains in that dirt were last lit by the Sun roughly 416,000 years ago, give or take 38,000, placing the site’s exposure in a warm interval known as MIS 11. It’s direct evidence that at least the far northwest of Greenland lost its ice then, a clue to how sensitive the ice sheet can be in natural warm periods.

Why it’s interesting

Fig. 014 The dark stratum marks grains last lit ~416 of 500 thousand years ago at Camp Century.

Why it’s interesting

Greenland’s ice sheet is not a single, eternal block; in a past warm spell, even its far northwest opened to air and plants. That makes the ice feel less like a monument and more like a living cover, advancing and retreating with climate.

The longer version

In the 1960s, a Cold War ice tunnel at Camp Century quietly pulled up a core that ended in frozen soil. Decades later, that rare subglacial material was re‑examined and found to hold plant and insect remains—signs of tundra, not ice. Independent teams then extracted chemical fingerprints that point to summers much like those of recent millennia.

Crucially, luminescence dating of sand grains shows when the soil last saw daylight: about 416,000 years ago, with a 38,000‑year uncertainty, aligning with Marine Isotope Stage 11. Together, the fossils, biomarkers and dates indicate the Camp Century area—and by extension parts of northwest Greenland—stood ice‑free during that warm span.

Edition: No. 014
Date: Tuesday 13 October 2026
Subject: Northwest Greenland
Locality: Camp Century, Greenland
Period: Marine Isotope Stage 11 (~416,000 years ago)
Field: earth
Evidence: 4 sources, 1 primary

See how we got here

Found after 34 research paths · Selected from 12 candidates

01 Ice ages Earth flips between colder and warmer states.
02 Greenland Ice Sheet Grows and shrinks with those swings.
03 Camp Century A 1960s ice core reached frozen soil.
04 Buried fossils Twigs and insect bits point to open ground.
05 Luminescence dating Grains last saw sunlight ~416 ka.
06 MIS 11 deglaciation Northwest Greenland stood ice‑free then.
→ Northwest Greenland was ice‑free about 400,000 years ago.

Sources

Nothing publishes without independent sources. How we verify →

1
Deglaciation of northwestern Greenland during Marine Isotope Stage 11
Science (AAAS) · 2023 · peer reviewed Primary

Direct evidence that northwestern Greenland (Camp Century region) was ice‑free during MIS 11; luminescence age of last exposure 416 ± 38 ka.

doi.org
2
Scientific history, sampling approach, and physical characterization of the Camp Century subglacial material, a rare archive from beneath the Greenland Ice Sheet
The Cryosphere · 2024 · peer reviewed

States explicitly that Christ et al. (2023) determined the uppermost subglacial sample was last exposed to sunlight at 416 ± 38 ka during MIS 11; documents plant/insect macrofossils indicating ice‑free conditions.

tc.copernicus.org
3
Holocene-like summer climate during Marine Isotope Stage 11 in northwestern Greenland
Climate of the Past · 2026 · peer reviewed

Uses biomarkers from Camp Century subglacial sediments to reconstruct MIS 11 climate; explicitly dates the studied interval to 416,000 ± 38,000 years ago during MIS 11, consistent with an ice‑free landscape.

cp.copernicus.org
4
Greenland Was Much Greener 416,000 Years Ago
Eos (AGU) · 2023 · journalism

Corroborates the Science paper’s findings, including the 416 ± 38 ka luminescence date and interpretation of deglaciation at Camp Century during MIS 11.

eos.org

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