Cited by 109Archaeology and ancient environmental studiesGeology and Paleoclimatology ResearchTree-ring climate responses

IntCal, SHCal, or a Mixed Curve? Choosing a14C Calibration Curve for Archaeological and Paleoenvironmental Records from Tropical South America

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Marsh, Erik J, Bruno, Maria C, Fritz, Sherilyn C, Baker, Paul, Capriles, José M, Hastorf, Christine A·2018·Radiocarbon

Abstract

Because the 14 C calibration curves IntCal and SHCal are based on data from temperate latitudes, it remains unclear which curve is more suitable for archaeological and paleoenvironmental records from tropical South America. A review of climate dynamics reveals a significant influx of Northern Hemisphere air masses and moisture over a substantial part of the continent during the South American Summer Monsoon (SASM). Areas affected by the SASM receive unknown amounts of input from both hemispheres, where an argument could be made for either curve. Until localized tree-ring data can resolve this, we suggest using a mixed calibration curve, which accounts for inputs from both hemispheres, as a third calibration option. We present a calibration example from a crucial period of environmental and cultural change in the southern Lake Titicaca. Given our current lack of data on past ∆14 C variation in South America, our calibrations and chronologies will likely change in the future. We hope this paper spurs new research into this topic and encourages researchers to make an informed and explicit choice of which curve to use, which is particularly relevant in research on past human–environmental relationships.

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Crossref · 10.1017/rdc.2018.16

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  • Trees growing within the ITCZ are potentially subjected to air masses from different hemispheres at certain times of the year.

    “Trees growing within the ITCZ are potentially subjected to air masses from different hemispheres at certain times of the year (Marsh et al. 2018; Hogg et al. 2020 in this issue).”

    From The IntCal20 Northern Hemisphere Radiocarbon Age Calibration Curve (0–55 cal kBP) (2020) · cites this paper as Marsh et al. 2018

    In “Defining Hemispheric Mixing and Air Mass Sources in Tropical South America” (p. 929), the paper describes southern Atlantic air reaching the Amazon Basin in austral winter and northern tropical Atlantic air dominating in austral summer. That supports the possibility of seasonal exposure to air from different hemispheres. But the paper says the ITCZ is an oceanic feature that does not extend across the continent, so it does not specifically describe trees as growing within the ITCZ. (LLM, conf=0.82)

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Research works printed but not linked: 5

  1. Jenkins HS. 2009. Amazon Climate Reconstruction Using Growth Rates and Stable Isotopes of Tree Ring Cellulose from the Madre de Dios Basin, Peru [PhD dissertation]. Durham, NC: Department of Earth & Ocean Sciences, Duke University.
  2. Lerman JC, Mook WG, Vogel JC. 1970. C 14 in tree rings from different localities. In: Olsson IU, editor. Radiocarbon Variations and Absolute Chronology, Proceedings, XII Nobel Symposium. Hoboken, NJ: John Wiley. p 275-301.
  3. Seltzer GO, Baker PA, Cross SL, Dunbar RB, Fritz SC. 1998. High-resolution seismic reflection profiles from Lake Titicaca, Peru-Bolivia: evi- dence for Holocene aridity in the tropical Andes. Geology 26(2):167-70.
  4. Turnbull JC, Graven H, Krakauer NY. 2016. Radio- carbon in the atmosphere. In: Schuur EAG, Druffel ERM, Trumbore SE, editors. Radio- carbon and Climate Change. New York: Springer. p 83-137.
  5. Xie P, Arkin PA. 1997. Global precipitation: a 17-year monthly analysis based on gauge observations, satellite estimates, and numerical model outputs. Bulletin of the American Meteorological Society 78:2539-58.

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Authors
Marsh, E. J., Bruno, M. C., Fritz, S. C., Baker, P., Capriles, J. M., & Hastorf, C. A.
Affiliations
  • Consejo Nacional de Investigaciones Científicas y Técnicas (AR)
  • Dickinson College (US)
  • University of Nebraska–Lincoln (US)
  • Duke University (US)
  • Pennsylvania State University (US)
  • University of California, Berkeley (US)
Corresponding author
Marsh, Erik J
Venue
Radiocarbon
Published
2018-03-16
Volume
60
Issue
3
Pages
925-940
ISSN
  • 0033-8222 (ISSN-L)
  • 1945-5755
OpenAlex
W2794208731
Cited by
109
References
89
Citations by year
2026: 10 · 2025: 12 · 2024: 10 · 2023: 16 · 2022: 13 · 2021: 14 · 2020: 17 · 2019: 15 · 2018: 2
FWCI
8.84
Type
journal article
Language
en
Open access
Locations
  • Radiocarbon (publishedVersion)
  • Lund University Publications (Lund University) (submittedVersion)
  • Conicet (submittedVersion, cc-by-nc-sa)
Funders
Consejo Nacional de Investigaciones Científicas y Técnicas
Topics
  • Physical Sciences › Earth and Planetary Sciences › Paleontology › Archaeology and ancient environmental studies
  • Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Geology and Paleoclimatology Research
  • Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Tree-ring climate responses
Keywords
radiocarbon calibration curve, tropical South America, South American Summer Monsoon, Lake Titicaca, archaeological chronology, paleoenvironmental records, human-environmental relationships, tree-ring measurements

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