Additional co-authors: TJ Heaton, AG Hogg, KA Hughen, KF Kaiser, B Kromer, SW Manning, RW Reimer, DA Richards, JR Southon, S Talamo, CSM Turney, J van der Plicht, CE Weyhenmeyer

/pdf/intcal13-and-marine13-radiocarbon-age-calibration-curves-0-4f3vsbzfqx.pdf

IntCal13 and Marine13 radiocarbon age calibration curves 0-50,000 years cal BP

The focus of this paper is the conversion of radiocarbon ages to calibrated (cal) ages for the interval 24,000-0 cal BP (Before Present, 0 cal BP = AD 1950), based upon a sample set of dendrochronologically dated tree rings, uranium-thorium dated corals, and varve-counted marine sediment. The 14C age-cal age information, produced by many laboratories, is converted to 14C profiles and calibration curves, for the atmosphere as well as the oceans. We discuss offsets in measured 14C ages and the errors therein, regional 14C age differences, tree-coral 14C age comparisons and the time dependence of marine reservoir ages, and evaluate decadal vs. single-year 14C results. Changes in oceanic deepwater circulation, especially for the 16,000-11,000 cal BP interval, are reflected in the Δ 14C values of INTCAL98.

/pdf/intcal98-radiocarbon-age-calibration-24-000-0-cal-bp-3stf38o5ox.pdf

INTCAL98 Radiocarbon Age Calibration, 24,000-0 cal BP

A new calibration curve for the conversion of radiocarbon ages to calibrated (cal) ages has been constructed and internationally ratified to replace IntCal98, which extended from 0-24 cal kyr BP (Before Present, 0 cal BP = AD 1950). The new calibration data set for terrestrial samples extends from 0-26 cal kyr BP, but with much higher resolution beyond 11.4 cal kyr BP than IntCal98. Dendrochronologically-dated tree-ring samples cover the period from 0-12.4 cal kyr BP. Beyond the end of the tree rings, data from marine records (corals and foraminifera) are converted to the atmospheric equivalent with a site-specific marine reservoir correction to provide terrestrial calibration from 12.4-26.0 cal kyr BP. A substantial enhancement relative to IntCal98 is the introduction of a coherent statistical approach based on a random walk model, which takes into account the uncertainty in both the calendar age and the 14C age to calculate the underlying calibration curve (Buck and Blackwell, this issue). The tree-ring data sets, sources of uncertainty, and regional offsets are discussed here. The marine data sets and calibration curve for marine samples from the surface mixed layer (Marine04) are discussed in brief, but details are presented in Hughen et al. (this issue a). We do not make a recommendation for calibration beyond 26 cal kyr BP at this time; however, potential calibration data sets are compared in another paper (van der Plicht et al., this issue).

/pdf/intcal04-terrestrial-radiocarbon-age-calibration-0-26-cal-4fi3x62yke.pdf

IntCal04 terrestrial radiocarbon age calibration, 0-26 cal kyr BP

http://ruby.fgcu.edu/courses/twimberley/envirophilo/wanner.pdf

Mid- to Late Holocene climate change: an overview

Stable isotopes in tree rings.

Volcanic eruptions contribute to climate variability, but quantifying these contributions has been limited by inconsistencies in the timing of atmospheric volcanic aerosol loading determined from ice cores and subsequent cooling from climate proxies such as tree rings. Here we resolve these inconsistencies and show that large eruptions in the tropics and high latitudes were primary drivers of interannual-to-decadal temperature variability in the Northern Hemisphere during the past 2,500 years. Our results are based on new records of atmospheric aerosol loading developed from high-resolution, multi-parameter measurements from an array of Greenland and Antarctic ice cores as well as distinctive age markers to constrain chronologies. Overall, cooling was proportional to the magnitude of volcanic forcing and persisted for up to ten years after some of the largest eruptive episodes. Our revised timescale more firmly implicates volcanic eruptions as catalysts in the major sixth-century pandemics, famines, and socioeconomic disruptions in Eurasia and Mesoamerica while allowing multi-millennium quantification of climate response to volcanic forcing.

/pdf/timing-and-climate-forcing-of-volcanic-eruptions-for-the-sw6kak6482.pdf

Timing and climate forcing of volcanic eruptions for the past 2,500 years

SUMMARY Radiocarbon dates for a number of pollen analytic features marking important vegetational changes in the Post-glacial of the British Isles are plotted in two figures (Figs. 2 and 3, summarized in Fig. 4). Despite the limitations of the radiocarbon method it becomes clear, where sufficient dates are available, that most of the vegetational developments of the earlier part of the Post-glacial are diachronous. Some of these changes have been used as pollen zone boundaries. The elm decline appears synchronous, however, within the limits of the methods, and the final pine decline in Ireland, which is shown to be older than supposed by Jessen (1949), appears to be one of the least diachronous of the horizons examined. Marked differences in the dates of similar vegetational changes within a small area, and between upland and lowland, are pointed out.

https://nph.onlinelibrary.wiley.com/doi/pdf/10.1111/j.1469-8137.1973.tb02066.x

Radiocarbon dates and vegetational history of the british isles

Long tree-ring chronologies provide a unique calendrical record that is of value for archaeological dating, climatic and post-glacial studies. They also form a standard for the calibration of the radiocarbon time scale. The world's longest continuous tree-ring chronology is based on the bristlecone pine (Pinus aristata and Pinus longaeva) growing in the White Mountains of California1–3. The great age of living and sub-fossil trees of this species enabled a continuous tree-ring sequence of 8,681 years to be established, providing absolutely dated wood samples for the first radiocarbon calibration4,5. We have now established an unbroken west European tree-ring sequence spanning the past 7,272 years.

A 7,272-year tree-ring chronology for western Europe

Discrete layers of tephra have been found in both raised and blanket bogs in the north of Ireland. Some of the layers have been identified to an Icelandic source and, in two cases, specific eruptions of known radiocarbon age are suggested. Nine layers spanning the Holocene are replicated in three lowland raised bogs. One of the major layers has also been identified at a number of sites in two separate upland blanket peat systems and in a lake sediment.

Towards a tephrochronology for the Holocene of the north of Ireland

/pdf/high-precision-super-14c-measurement-of-irish-oaks-to-show-3kj9lmi5au.pdf

Jonathan R. Pilcher

Papers

Timing and climate forcing of volcanic eruptions for the past 2,500 years

Radiocarbon dates and vegetational history of the british isles

A 7,272-year tree-ring chronology for western Europe

Towards a tephrochronology for the Holocene of the north of Ireland

High-precision (super 14C measurement of Irish oaks to show the natural 14C variations from AD 1840-5210 BC.