Publication Date:
2024-03-02
Description:
Long, continuous, marine sediment records from the subpolar North Atlantic document the glacial modulation of regional climate instability throughout the past 0.5 million years. Whenever ice sheet size surpasses a critical threshold indicated by the benthic oxygen isotope (delta18O) value of 3.5 per mil during each of the past five glaciation cycles, indicators of iceberg discharge and sea-surface temperature display dramatically larger amplitudes of millennial-scale variability than when ice sheets are small. Sea-surface temperature oscillations of 1° to 2°C increase in size to approximately 4° to 6°C, and catastrophic iceberg discharges begin alternating repeatedly with brief quiescent intervals. The glacial growth associated with this amplification threshold represents a relatively small departure from the modern ice sheet configuration and sea level. Instability characterizes nearly all observed climate states, with the exception of a limited range of baseline conditions that includes the current Holocene interglacial.
Keywords:
162-980; AGE; Cibicidoides wuellerstorfi, δ13C; Cibicidoides wuellerstorfi, δ18O; COMPCORE; Composite Core; DEPTH, sediment/rock; Joides Resolution; Leg162; Mass spectrometer Finnigan MAT 252; Ocean Drilling Program; ODP; South Atlantic Ocean
Type:
Dataset
Format:
text/tab-separated-values, 652 data points
Permalink
