Köhler, Peter; Skinner, Luke C; Adolphi, Florian (2024): Splines of reconstructed deep ocean 14C ages over that last 25 kyr and simulation results of the carbon and radiocarbon cycle across the last 55 kyr [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.967149

Carbon cycle models used to interpret the IntCal20 compilation of atmospheric ∆14C have so far neglected a key aspect of the millennial-scale variability connected with the thermal bipolar seesaw: changes in the strength of the Atlantic meridional overturning circulation (AMOC) related to Dansgaard/Oeschger and Heinrich events. Here we implement such AMOC changes in the carbon cycle box model BICYCLE-SE to investigate how model performance over the last 55,000 years is affected, in particular with respect to available 14C and CO2 data. Thus, this data set contains: (a) Carbon cycle simulation output of the BICYCLE-SE model covering the last 55,000 years consisting of changes in marine reservoir age (MRA) of the whole ocean, or of the deep ocean in different basins (Atlantic, Southern Ocean, Indo-Pacific), non-polar surface ocean MRA, atmospheric CO2, atmospheric D14C, 14C production rates in 18 scenarios, which differ in boundary conditions (prescription of atmospheric carbon inventories) and changes in the strength of the AMOC in order to meet changes in marine 14C age as provided by data. (b) Six splines of intermediate (0.2-2.0 km) and deep (>2km) ocean marine reservoir age in Atlantic, Southern Ocean, Indo-Pacificof the past 25,000 years based on benthic 14C data as compiled in Skinner et al., 2023 (doi: 10.5194/cp-19-2177-2023), related to data set doi:10.1594/PANGAEA.960693.

README file for the data archive, which contains the following files:

-

Simulation results (55 kyr long) using the BICYCLE-SE model for 6 scenarios (CTRL, A0, A1, A2, A3, Ac) in 3 baselines (Q1, V1, V1CO2) leading to 18 results files labelled

BICYCLE-SE_[BASELINE][SCENARIO]_55ka_variousDeltaMRA_eqsurfMRA[ADDITIONAL]_withheader.dat

-

=> where [BASELINE] and [SCENARIO] are filled accordingly and

=> [ADDITIONAL]: is either atmD14C_CO2 (baseline Q1) or Q (baselines V1, V1CO2).

-

The 14C production rate Q contained in baselines V1 and V1CO2 is calculated as 400-years running mean values from annual output.

Therefore, Q contains no output for the last 200 years marked by NaN (not a number).

-

Data compilation: six 25-kyr long splines of marine reseroir age (MRA) based on benthic 14C data derived from the baseline data selection in Skinner et al. (2023), doi: 10.5194/cp-19-2177-2023.

-

=> data_splines_MRA_Atlantic_intermediate_25ka_withheader.dat

=> data_splines_MRA_Atlantic_deep_25ka_withheader.dat

=> data_splines_MRA_SouthernOcean_intermediate_25ka_withheader.dat

=> data_splines_MRA_SouthernOcean_deep_25ka_withheader.dat

=> data_splines_MRA_IndoPacific_intermediate_25ka_withheader.dat

=> data_splines_MRA_IndoPacific_deep_25ka_withheader.dat

-

The contained data are indicated by the file names and details are giving in the headers.