Ice cores contain trapped air bubbles that reveal the composition of ancient atmospheres, including carbon dioxide and methane levels.
Notes on verification
Confirmed by multiple authoritative and peer-reviewed sources including NASA, NOAA, NSIDC, and glaciology research; well-established scientific consensus. [tier=gold indep_score=0.925 clusters=4 claim_tier=everyday]
Sources
- Greenland Ice-core Project/Greenland Ice Sheet Project 2 | geochronology | Britannica (seed:history_and_archaeology)
- https://science.nasa.gov/earth/earth-observatory/paleoclimatology-the-ice-core-record/ (corroboration)
- https://gml.noaa.gov/outreach/faq_cat-3.html (corroboration)
- https://nsidc.org/learn/ask-scientist/core-climate-history (corroboration)
- https://www.antarcticglaciers.org/glaciers-and-climate/ice-cores/ice-core-basics/ (corroboration)