Data copyright © Prof N. J. Loader, Prof D. McCarroll, Dr G. H. F. Young, Dr D. Miles, Prof Christopher Bronk Ramsey unless otherwise stated
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Prof
N. J.
Loader
Department of Geography
University of Swansea
Singleton Park
Swansea
SA2 8PP
Wales
To better-understand natural hydroclimate variability and to help place recent climatic change within a longer-term perspective, a reconstruction of summer precipitation was developed based upon the oxygen isotope ratios of precisely-dated latewood alpha-cellulose from oak tree rings. Oxygen isotopes in precipitation are closely related to precipitation variability across the UK, enabling the reconstruction to be used to extend May to August precipitation totals for the England and Wales precipitation series back to 1201CE.
The agreement between instrumental and reconstructed values is unusually strong, with more than half of the variance explained and standard verification tests passed. The stability of this relationship is confirmed using split-period calibration and verification. This allows the reconstruction to be variance-scaled to the full length of the England and Wales instrumental series back to 1766CE.
Near-constant replication, with a minimum of ten timbers sourced from historic buildings across central southern England ensures signal strength does not change over time. Summers during the late 20th century appear anomalously dry and those of the 21st century very close to the pre-20th century average with no evidence in the record of prolonged ‘megadroughts’ across England and Wales.
For further details and citation when using these data:
Loader, N.J., Young, G.H.F., McCarroll, D., Davies, D., Miles, D., and Bronk Ramsey, C. (2020), Summer Precipitation for the England and Wales region, 1201 - 2000CE, from Stable Oxygen Isotopes in oak tree rings. J. Quaternary Sci. doi:10.1002/jqs.3226
Loader, N.J., McCarroll, D., Miles, D., Young, G.H.F., Davies, D. and Bronk Ramsey, C. (2019), Tree ring dating using oxygen isotopes: a master chronology for central England. J. Quaternary Sci., 34: 475-490. doi:10.1002/jqs.3115