Change Log

Updated versions of the Northern and Southern Hemisphere Zones by Hua et al have been incorporated. These are considered replacements for some of the previously used data sets.

The CALIBomb software has been updated to execute client-side rather than server-side

A multi-sample calibration capability has been added through the 'Advanced' link.

Levin dataset was updated to include bi-weekly measurements through August 2019

Levin dataset was updated to include monthly means of Schauinsland measurements through 2016

Added single year pine data from Brazil to the post-bomb calibration curve selection. This dataset extends back to 1928 and cannot be merged with IntCal.

Santos GM, Linares R, Lisi CS and Tomazello Filho M. 2015. Annual growth rings in a sample of ParanĂ¡ pine (Araucaria angustifolia): Toward improving the 14C calibration curve for the Southern Hemisphere, Quaternary Geochronology 25:96-103, doi: 10.1016/j.quageo.2014.10.004

Modified the curve smoothing algorithm. Previously, the uncertainty on the smoothed curve was taken as the maximum of the variance within the smoothing window and the average uncertainty. This caused inappropriately large uncertainties to develop in the rapidly changing portion of the bomb curve. The smoothed curve uncertainty is now just the average uncertainty in the smoothing window.

Be aware that smoothing truncates the calibration curve, leading to "end of data set" effects on the cal ranges. On which end of the curve these effects occur depends on whether results are shown as cal BP or cal AD/BC. The "end of dataset effect" indicator [*] has been made to work for both cal BP and cal AD/BC.

Added the UW single year tree ring dataset from 1998 as a pre-bomb calibration dataset.

In the continuing quest to combat hackers, CALIB has been modified not to write any files on the server. This resulted in the format of the plot image being changed to SVG. Use Adobe Illustrator or the free software, Inkscape, to manipulate the downloaded file. If your web browser is Internet Explorer you'll simply get a png file when you download the image

The Levin et al. dataset has been extended into 2012 with the addition of data published in Tellus B 2013, 65, 20092

The Hua, et al. compilation datasets have been updated and extended to 2010 / 2011.

The Levin et al. dataset has been extended to 2007 with the addition of data published in Science of the Total Environment 391:211-216. Monthly means from Schauinsland have been appended to the 2004 version of the dataset.