Atmospheric CO₂ reaches a minimum recorded in Antarctic ice
Ice cores from Antarctica record a decline in atmospheric carbon dioxide through the late sixteenth century to a minimum around 1610. Lewis and Maslin proposed in 2015 that the dip is the atmospheric trace of the American population collapse, as tens of millions of hectares of managed land reverted to vegetation, and put it forward as a candidate marker for the start of the Anthropocene. The attribution and the boundary are both contested, and the stratigraphic community subsequently favoured a mid-twentieth-century marker.
Observed — measured or witnessed, with the observation cited.
Subjects
- The 1610 CO₂ minimum ("Orbis spike") · phenomenon · Global; measured in Antarctic ice cores · not located
- The post-contact population collapse of the Americas · phenomenon · The Americas · not located
Evidence
Partly verified — Core facts are sourced; some optional detail is deliberately absent. This is the standing of the weakest source, not an average.
Defining the Anthropocene
The proposal that the c. 1610 minimum in the Antarctic ice-core CO₂ record be adopted as the marker for the start of the Anthropocene, on the argument that it records vegetation regrowth following the American population collapse. V55 verification basis: NOT consulted in this session — no network access. The volume number is given from the author's knowledge; pagination is deliberately omitted.
Nature · 2015 · Partly verified
Simon L. Lewis and Mark A. Maslin, "Defining the Anthropocene", Nature, vol. 519 (2015)
Earth system impacts of the European arrival and Great Dying in the Americas after 1492
Supports the reconstruction of pre-contact American population, the scale of post-contact decline, the area of farmland abandoned and the resulting drawdown of atmospheric CO₂. V55 verification basis: NOT consulted in this session — no network access was available. The Journey declaration itself cites this paper as "Quaternary Science Reviews 207, 13", which corroborates the volume but is not independent confirmation. Every figure this pack attributes to it is flagged in the citing object's `missing` list as requiring a check against the paper.
Quaternary Science Reviews · 2019 · Partly verified
Alexander Koch, Chris Brierley, Mark M. Maslin and Simon L. Lewis, Quaternary Science Reviews, vol. 207 (2019)
Recorded on The 1610 CO₂ minimum ("Orbis spike")
- Smallpox reaches Tenochtitlan
- Atmospheric CO₂ reaches a minimum recorded in Antarctic ice
Related
Related because they share a subject in the Atlas — never because the text looks similar.
- Smallpox reaches Tenochtitlan · 1520 (autumn–winter)