Radiocarbon Concentration in the Atmosphere: 8000-Year Record of Variations in Tree Rings: First Results of a USA Workshop

Radiocarbon dates calculated from the ratio of modern carbon-14 activity and sample activity and the half-life of carbon-14 need to be calibrated to compensate for temporal variations in the concentration of carbon-14 in the atmosphere. Development of a suitable calibration scheme has been an ongoing process of the last twenty years, ever since the discovery of variations in historical times of the atmospheric radiocarbon content which parallel climatic and solar phenomena (de Vries, 1958; 1959) and the recent depletion due to industrial effects (Suess, 1955).

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Relative and absolute dating of four late Neolithic enclosures: an exercise in the interpretation of radiocarbon determinations

Proceedings of the Prehistoric Society ◽

10.1017/s0079497x00012184 ◽

1972 ◽

Vol 38 ◽

pp. 389-407 ◽

Cited By ~ 4

Author(s):

R. Burleigh ◽

I. H. Longworth ◽

G. J. Wainwright

Keyword(s):

Fine Structure ◽

Half Life ◽

General Trend ◽

Detailed Structure ◽

Late Neolithic ◽

Archaeological Evidence ◽

Radiocarbon Dates ◽

Carbon 14 ◽

Absolute Dating

SummaryIf the fine structure of the carbon-14 deviation curve published by Professor H. E. Suess (in Proceedings of the 12th Nobel Symposium, I. U. Olsson (ed.), 1970) is correct, then the period from c. 2200 bc to c. 1700 bc in radiocarbon years falls within one of the insensitive regions in which carbon-14 determinations could have a number of alternative chronological values and hence could not be used to order archaeological evidence. Without disputing the now well established general trend of radiocarbon variation, it is the purpose of this paper to suggest, from recurrent evidence drawn from four recently studied Late Neolithic enclosures, that the detailed structure of Suess' curve is not necessarily valid. Uncalibrated radiocarbon dates based on the conventional 5570 year half-life of carbon-14 are used throughout this paper.

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C14 dates from the Scoresby Sund region, 1973

Rapport Grønlands Geologiske Undersøgelse ◽

10.34194/rapggu.v58.7368 ◽

1973 ◽

Vol 58 ◽

pp. 75-76

Author(s):

S Funder

Keyword(s):

Lake Sediment ◽

Half Life ◽

Marine Bivalve ◽

National Museum ◽

Radiocarbon Dates ◽

Carbon 14

Radiocarbon dates have been obtained on samples of lake sediment and marine bivalve shelIs collected by the author in 1971. The dating has been carried out by H. Tauber, the Carbon-14 Dating Laboratory at the National Museum, Copenhagen. The ages are expressed as uncorrected C14 years based on the conventional half life for C14 of 5570 years.

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Copenhagen Radiocarbon Dates IX

Radiocarbon ◽

10.1017/s0033822200010912 ◽

1968 ◽

Vol 10 (2) ◽

pp. 295-327 ◽

Cited By ~ 26

Author(s):

Henrik Tauber

Keyword(s):

Oxalic Acid ◽

Half Life ◽

Isotopic Fractionation ◽

Radiocarbon Dates ◽

Unknown Sample ◽

De Vries ◽

Standard Deviations

The following list comprises a selected number of measurements made up to October, 1967. Age calculations are based on 95% of the activity of the NBS oxalic-acid standard, and on a half-life for C14 of 5570 yr. Results are reported in yr before 1950, and in the A.D./B.C. scale.Errors quoted include standard deviations of the count rates for the unknown sample, contemporary value, and background. Because possible errors arising from isotopic fractionation in the plants, or from the de Vries effect, have not been included, calculated errors smaller than 100 yr have been increased by rounding to that figure as a minimum.Sample descriptions have been prepared in collaboration with collectors and submitters.

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University of Pennsylvania Radiocarbon Dates IV

Radiocarbon ◽

10.1017/s0033822200020786 ◽

1961 ◽

Vol 3 ◽

pp. 4-14 ◽

Cited By ~ 17

Author(s):

Elizabeth K. Ralph ◽

Robert E. Ackerman

Keyword(s):

Carbon Dioxide ◽

Tree Rings ◽

University Of Pennsylvania ◽

Solid Carbon ◽

Original Publication ◽

Radiocarbon Dates ◽

Suess Effect ◽

De Vries

With one exception, the radiocarbon dates in this list were reported previously by Rainey and Ralph (1959). For discussions of the reliability of the dates, of the materials dated, and of the correspondence of the dates with estimated arctic chronologies, the reader is urged to refer to the original publication. The radiocarbon determinations were made over a period of several years. Those processed before 1956 were dated by the solid-carbon method and are so labeled; others, by the carbon-dioxide method. The age calculations are based on the average of several samples dated archaeologically and by tree-rings, corrected to zero age (Rainey and Ralph, 1959, p. 365). By this means the errors due to atmospheric depletion (Suess effect) and to past changes in radiocarbon concentration (de Vries, 1958; Willis, Tauber, and Münnich, 1960) have been minimized. The b.p. dates are calculated from A.D. 1957 (solid-carbon) and A.D. 1958 (carbon dioxide).

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Gliwice Radiocarbon Dates V

Radiocarbon ◽

10.1017/s0033822200004343 ◽

1979 ◽

Vol 21 (2) ◽

pp. 165-170 ◽

Cited By ~ 5

Author(s):

Anna Pazdur ◽

Mieczyslaw F Pazdur ◽

Andrzej Zastawny

Keyword(s):

Oxalic Acid ◽

Half Life ◽

Counting Efficiency ◽

Radiocarbon Dates ◽

Unknown Sample ◽

De Vries ◽

Standard Value ◽

Standard Deviations ◽

Contemporary Standard

Most of the dates reported in this list were obtained between November 1975 and December 1976. All samples were subjected to standard de Vries pretreatment. Age calculations are based on a contemporary value equal to 0.95 of the activity of NBS oxalic acid standard and on the Libby value for the half-life of radiocarbon. Results are reported as conventional radiocarbon dates in years before ad 1950. All measurements were made with our L1 counter (Mościcki & Zastawny, 1976). Counting rates of all samples were normalized to the standard value of CO2 pressure and corrected for the counting efficiency (Pazdur et al, 1978). Errors quoted (±1σ) include estimated overall standard deviations of count rates for the unknown sample, contemporary standard and background (Pazdur, & Walanus, in press). No corrections for 13C/12C ratio were made for measurements reported in this list. The value of δ13C for our NBS oxalic acid standard is equal to — 19.41% relative to the PDB standard. The descriptions of the samples are based on information provided by the submitters.

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Copenhagen Radiocarbon Dates VII

Radiocarbon ◽

10.1017/s0033822200000126 ◽

1966 ◽

Vol 8 ◽

pp. 213-234 ◽

Cited By ~ 19

Author(s):

Henrik Tauber

Keyword(s):

Oxalic Acid ◽

Half Life ◽

Isotopic Fractionation ◽

Radiocarbon Dates ◽

Unknown Sample ◽

De Vries ◽

Standard Deviations

The following list comprises a selected number of measurements made up to November, 1965. Age calculations are based on a contemporary value equal to 95% of the activity of the NBS oxalic-acid standard, and on a half life for C14 of 5570 yr. Results are reported in years before 1950, and in the A.D./B.C. scale. Errors quoted include the standard deviations of the count rates for the unknown sample, the contemporary value, and the background. Because possible errors arising from isotopic fractionation in the plants, or from the de Vries effect, have not been included, calculated errors smaller than 100 yr have been increased by rounding to that figure as a minimum.

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The spatiotemporal distribution of historical malaria cases in Sweden: a climatic perspective

Malaria Journal ◽

10.1186/s12936-021-03744-9 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Tzu Tung Chen ◽

Fredrik Charpentier Ljungqvist ◽

Helene Castenbrandt ◽

Franziska Hildebrandt ◽

Mathias Mølbak Ingholt ◽

...

Keyword(s):

Severe Malaria ◽

Hot Spots ◽

Climatic Variability ◽

Warm Season ◽

Temporal Variations ◽

Malaria Vectors ◽

Military Hospital ◽

Climate Variables ◽

Superposed Epoch Analysis ◽

Historical Times

Abstract Background Understanding of the impacts of climatic variability on human health remains poor despite a possibly increasing burden of vector-borne diseases under global warming. Numerous socioeconomic variables make such studies challenging during the modern period while studies of climate–disease relationships in historical times are constrained by a lack of long datasets. Previous studies have identified the occurrence of malaria vectors, and their dependence on climate variables, during historical times in northern Europe. Yet, malaria in Sweden in relation to climate variables is understudied and relationships have never been rigorously statistically established. This study seeks to examine the relationship between malaria and climate fluctuations, and to characterise the spatio-temporal variations at parish level during severe malaria years in Sweden 1749–1859. Methods Symptom-based annual malaria case/death data were obtained from nationwide parish records and military hospital records in Stockholm. Pearson (rp) and Spearman’s rank (rs) correlation analyses were conducted to evaluate inter-annual relationship between malaria data and long meteorological series. The climate response to larger malaria events was further explored by Superposed Epoch Analysis, and through Geographic Information Systems analysis to map spatial variations of malaria deaths. Results The number of malaria deaths showed the most significant positive relationship with warm-season temperature of the preceding year. The strongest correlation was found between malaria deaths and the mean temperature of the preceding June–August (rs = 0.57, p < 0.01) during the 1756–1820 period. Only non-linear patterns can be found in response to precipitation variations. Most malaria hot-spots, during severe malaria years, concentrated in areas around big inland lakes and southern-most Sweden. Conclusions Unusually warm and/or dry summers appear to have contributed to malaria epidemics due to both indoor winter transmission and the evidenced long incubation and relapse time of P. vivax, but the results also highlight the difficulties in modelling climate–malaria associations. The inter-annual spatial variation of malaria hot-spots further shows that malaria outbreaks were more pronounced in the southern-most region of Sweden in the first half of the nineteenth century compared to the second half of the eighteenth century.

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Erratum: Corrigendum: Another rapid event in the carbon-14 content of tree rings

Nature Communications ◽

10.1038/ncomms3747 ◽

2013 ◽

Vol 4 (1) ◽

Cited By ~ 1

Author(s):

Fusa Miyake ◽

Kimiaki Masuda ◽

Toshio Nakamura

Keyword(s):

Tree Rings ◽

Carbon 14

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Copenhagen Radiocarbon Dates VI

Radiocarbon ◽

10.1017/s0033822200010699 ◽

1964 ◽

Vol 6 ◽

pp. 215-225 ◽

Cited By ~ 19

Author(s):

Henrik Tauber

Keyword(s):

Oxalic Acid ◽

Half Life ◽

Radiocarbon Dates ◽

Unknown Sample ◽

Minimum Sample ◽

Standard Deviations

The following list comprises a selected number of measurements made up to November 1963. Age calculations are based on a contemporary value equal to 95% of the activity of the NBS oxalic-acid standard, and on a half life for C14 of 5570 ± 30 yr.Results are expressed in years before 1950 and in the b.c.-a.d. scales. Errors quoted include the standard deviations of the count rates for the unknown sample, the contemporary value, and the background. Calculated errors smaller than 100 yr have been increased by rounding to that figure as a minimum. Sample descriptions have been prepared in collaboration with collectors and submitters.

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