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Abstract: The concentration of radiocarbon (14C) differs between ocean and atmosphere. Radiocarbon determinations from samples which obtained their 14C in the marine environment therefore need a marine-specific calibration curve and cannot be calibrated directly against the atmospheric-based IntCal20 curve. This paper presents Marine20, an update to the internationally-agreed marine radiocarbon age calibration curve that provides a non-polar global-average marine record of radiocarbon from 0 – 55 cal kBP and serves as a baseline for regional oceanic variation. Marine20 is based upon 500 simulations with an ocean/atmosphere/biosphere box-model of the global carbon cycle that has been forced by posterior realisations of our Northern Hemispheric atmospheric IntCal20 14C curve and reconstructed changes in CO2 obtained from ice core data. These forcings enable us to incorporate carbon cycle dynamics and temporal changes in the atmospheric 14C level. The box-model simulations of the global-average marine radiocarbon reservoir age are similar to those of a more complex three-dimensional ocean general circulation model. However, simplicity and speed of the box model allow us to use a Monte Carlo approach to rigorously propagate the uncertainty in both the historic concentration of atmospheric 14C and other key parameters of the carbon cycle through to our final Marine20 calibration curve. This robust propagation of uncertainty is fundamental to providing reliable precision for the radiocarbon age calibration of marine based samples. We make a first step towards deconvolving the contributions of different processes to the total uncertainty; discuss the main differences of Marine20 from the previous age calibration curve Marine13; and identify the limitations of our approach together with key areas for further work. The updated values for 𝛥𝑅, the regional marine radiocarbon reservoir age corrections required to calibrate against Marine20, can be found at the data base http://calib.org/marine/. This data set includes: - the data plotted in the related manuscript, including Marine20, and IntCal20, the most recent version of the radiocarbon age calibration curves - the 500 northern hemispheric atmospheric Δ14C realisations of IntCal20 used as input for the calculation of Marine20 - a netCDF file from the LSG OCGCM with spatially resolved marine reservoir ages. Category: geoscientificInformation Source: Not Available Supplemental Information: The netCDF file included here contains results of marine reservoir age (MRA) simulations applying the LSG ocean general circulation model forced with various climatic background conditions and with atmospheric radiocarbon changes according to the IntCal20 reconstruction for the years 55,000-0 cal BP (one data point every 50 years), oceanic depth range, from which the MRA has been calculated, is 0-50 m. Land values are flagged with -100. The different results denote upper (MRA_MAX) and lower (MRA_MIN) bounds as well as the average (MRA_AVG) and the median (MRA_MED) of the ensemble of nine simulations ((3 versions of atmosheric Delta14C from IntCal20) x (3 climate forcing scenarios)). The range of results decreases for 10,700-0 cal BP, since this period covers only 3 ensemble members based on one climate forcing. This dataset complements PANGAEA dataset doi.pangaea.de/10.1594/PANGAEA.902301, which was used in the construction of IntCal20 and employed preliminary atmospheric radiocarbon forcing based on the Hulu Cave speleothem record. Coverage: Not Available
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Abstract: Not Available Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: (COR-02B) * LATITUDE: 38.144800 * LONGITUDE: 22.758400 * DATE/TIME: 2017-11-12T00:00:00 * IGSN: hdl:10273/IBCR0381EH80001 * LOCATION: Gulf of Corinth * CAMPAIGN: Exp381 * BASIS: Fugro Synergy * METHOD/DEVICE: Core
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Abstract: Not Available Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: (GeoB22605-1) * LATITUDE: 43.947133 * LONGITUDE: 30.799650 * DATE/TIME: 2017-11-15T00:00:00 * ELEVATION: -868.0 m * CAMPAIGN: M142 * BASIS: Meteor (1986) * METHOD/DEVICE: MeBo200
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Abstract: Not Available Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: (COR-02B) * LATITUDE: 38.144800 * LONGITUDE: 22.758400 * DATE/TIME: 2017-11-12T00:00:00 * IGSN: hdl:10273/IBCR0381EH80001 * LOCATION: Gulf of Corinth * CAMPAIGN: Exp381 * BASIS: Fugro Synergy * METHOD/DEVICE: Core
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Abstract: Not Available Category: geoscientificInformation Source: Not Available Supplemental Information: Samples were taken during expeditions PS103 by 20 µm mesh size plankton nets from ca. 15 to 0 m depth. To obtain clean siliceous diatom frustules, the samples were oxidized using hydrochloric acid and potassium permanganate and mounted on coverslips on standard microscopic slides in Naphrax resin. Classes ID: Asteromphalus.labId_6835 0 Chaetoceros.labId_6813 1 Fragilariopsis kerguelensis.labId_8356 2 Fragilariopsis rhombica.labId_8362 3 Nitzschia.labId_6758 4 Pseudonitzschia.labId_8364 5 Rhizosolenia.labId_6776 6 Silicoflagellate.labId_10255 7 Thalassiosira gracilis.labId_10366 8 Thalassiosira lentiginosa.labId_10369 9 Coverage: EVENT LABEL: * LATITUDE: -45.955810 * LONGITUDE: 6.287500 * DATE/TIME: 2016-12-20T13:10:00 * ELEVATION: -2621.0 m * LOCATION: South Atlantic Ocean * CAMPAIGN: PS103 * BASIS: Polarstern * METHOD/DEVICE: Hand net EVENT LABEL: * LATITUDE: -49.015500 * LONGITUDE: 2.841360 * DATE/TIME: 2016-12-21T14:37:00 * ELEVATION: -4065.0 m * LOCATION: South Atlantic Ocean * CAMPAIGN: PS103 * BASIS: Polarstern * METHOD/DEVICE: Hand net EVENT LABEL: * LATITUDE: -51.994080 * LONGITUDE: 2.100740 * DATE/TIME: 2016-12-22T13:20:00 * ELEVATION: -2836.0 m * LOCATION: South Atlantic Ocean * CAMPAIGN: PS103 * BASIS: Polarstern * METHOD/DEVICE: Hand net EVENT LABEL: * LATITUDE: -55.876840 * LONGITUDE: 1.055580 * DATE/TIME: 2016-12-23T13:06:00 * ELEVATION: -4037.0 m * LOCATION: South Atlantic Ocean * CAMPAIGN: PS103 * BASIS: Polarstern * METHOD/DEVICE: Hand net EVENT LABEL: * LATITUDE: -59.049620 * LONGITUDE: 0.079860 * DATE/TIME: 2016-12-24T09:53:00 * ELEVATION: -4652.0 m * LOCATION: South Atlantic Ocean * CAMPAIGN: PS103 * BASIS: Polarstern * METHOD/DEVICE: Hand net EVENT LABEL: * LATITUDE: -61.000580 * LONGITUDE: -0.001770 * DATE/TIME: 2016-12-25T08:10:00 * ELEVATION: -5161.0 m * LOCATION: Weddell Sea * CAMPAIGN: PS103 * BASIS: Polarstern * METHOD/DEVICE: Hand net EVENT LABEL: * LATITUDE: -63.993780 * LONGITUDE: 0.061890 * DATE/TIME: 2016-12-26T18:58:00 * ELEVATION: -5197.0 m * LOCATION: South Atlantic Ocean * CAMPAIGN: PS103 * BASIS: Polarstern * METHOD/DEVICE: Hand net EVENT LABEL: * LATITUDE: -66.001220 * LONGITUDE: 0.004050 * DATE/TIME: 2016-12-27T14:17:00 * ELEVATION: -3421.0 m * LOCATION: Lazarev Sea * CAMPAIGN: PS103 * BASIS: Polarstern * METHOD/DEVICE: Hand net
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Abstract: Not Available Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: (COR-04A) * LATITUDE: 38.120000 * LONGITUDE: 23.086300 * DATE/TIME START: 2017-12-02T00:00:00 * DATE/TIME END: 2017-12-15T00:00:00 * IGSN: hdl:10273/IBCR0381EHG0001 * LOCATION: Gulf of Corinth * CAMPAIGN: Exp381 * BASIS: Fugro Synergy * METHOD/DEVICE: Core
Data Types:
  • Tabular Data
Abstract: Not Available Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: (GeoB22611-1) * LATITUDE: 43.948383 * LONGITUDE: 30.783633 * DATE/TIME: 2017-11-25T00:00:00 * ELEVATION: -788.0 m * CAMPAIGN: M142 * BASIS: Meteor (1986) * METHOD/DEVICE: Gravity corer
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Abstract: Not Available Category: geoscientificInformation Source: Not Available Supplemental Information: #0 = below detection limit Coverage: EVENT LABEL: * LATITUDE: -52.200000 * LONGITUDE: -59.060000 * LOCATION: Falkland Islands * METHOD/DEVICE: Biology
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Abstract: Lake Teletskoye (spanning 51°20′ to 51°47′N and 87°15′ to 87°50′E) is the largest lake in the Altai Mountains and is 77 km long and 330 m deep.The core location (51°44.99′N, 87°37.414′E) was at the deepest part of the lake. The altitude of the mountains surrounding the lake is 1900 m a.s.l. on average. Due to higher annual precipitation at the area, the steppe belt is absencent but it occurs, at least fragmentarily, in other parts of the mountains. Only very small patches along the lakeshore represent steppe-like vegetation. Birch forests mixed with meadows occur at lower altitudes, up to 700 m a.s.l. Unique evergreen (so-called 'dark') coniferous forest grow between 700 and 1700ma.s.l. The mountains above 1700 m are covered by Siberian pine (Pinus sibirica) forest. Above the tree line, at about 1800 m, alpine tundra and alpine meadow communities are widespread. Dating was complicated by the absence of plant macrofossils in the sediments and low bulk TOC. To obtain a more reliable chronology, the 210Pb activity and 137Cs content were also analysed. For more details see Rudaya et al., 2016. Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: Not Available
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Abstract: Not Available Category: geoscientificInformation Source: Not Available Supplemental Information: Not Availble Coverage: EVENT LABEL: (COR-01A) * LATITUDE: 38.158400 * LONGITUDE: 22.695400 * DATE/TIME START: 2017-11-14T00:00:00 * DATE/TIME END: 2017-11-29T00:00:00 * IGSN: hdl:10273/IBCR0381EHB0001 * LOCATION: Gulf of Corinth * CAMPAIGN: Exp381 * BASIS: Fugro Synergy * METHOD/DEVICE: Core
Data Types:
  • Tabular Data