The onsets of all events BMX-IN-1 listed in Table 2 together with estimated uncertainties. The latter have been estimated from the steepness of the transitions and the level of agreement between the δ18O and [Ca2+] records. Some of the uncertainties assigned to the event definitions in the previously-published 8–48 ka b2k interval have been re-evaluated based on the augmented data set.
Table 2.
5.1. Adjusting the existing event stratigraphy (8–48 ka b2k)
The onsets of GS-1 and GI-1 in the INTIMATE event stratigraphy scheme are defined on the basis of high-resolution![BMX-IN-1]()
multi-proxy ice-core data (Steffensen et al., 2008). Of particular significance are deuterium excess values, and this data set was the principal climatic indicator that underpinned the formal designation of the Holocene Global Stratotype Section and Point (GSSP) boundary in the NGRIP ice core (Walker et al., 2009). Deuterium excess is interpreted as a proxy for precipitation vapour source temperature and is shown to change between states in 1–3 years at the onsets of GI-1 and GS-1. The shifts in δ18O and [Ca2+] are more gradual and begin no more than a couple of decades after the abrupt deuterium excess changes.
Table 2.
5.1. Adjusting the existing event stratigraphy (8–48 ka b2k)
The onsets of GS-1 and GI-1 in the INTIMATE event stratigraphy scheme are defined on the basis of high-resolution
multi-proxy ice-core data (Steffensen et al., 2008). Of particular significance are deuterium excess values, and this data set was the principal climatic indicator that underpinned the formal designation of the Holocene Global Stratotype Section and Point (GSSP) boundary in the NGRIP ice core (Walker et al., 2009). Deuterium excess is interpreted as a proxy for precipitation vapour source temperature and is shown to change between states in 1–3 years at the onsets of GI-1 and GS-1. The shifts in δ18O and [Ca2+] are more gradual and begin no more than a couple of decades after the abrupt deuterium excess changes.