z-logo
open-access-imgOpen Access
Climatologic and hydrologic influences on the oxygen isotope ratio of tree cellulose in coastal southern California during the late 20th century
Author(s) -
Kanner Lisa,
Buenning Nikolaus,
Stott Lowell,
Stahle Dave
Publication year - 2013
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1002/ggge.20256
Subject(s) - δ18o , dendrochronology , environmental science , cellulose , precipitation , isotopes of oxygen , proxy (statistics) , stable isotope ratio , atmospheric sciences , relative humidity , paleoclimatology , climatology , physical geography , geology , climate change , oceanography , chemistry , geography , geochemistry , meteorology , paleontology , physics , organic chemistry , quantum mechanics , machine learning , computer science
The oxygen isotope ratio ( δ 18 O) of precipitation in continental, midlatitude regions is a complex measure of atmospheric dynamics and regional climate variability and can be preserved in geologic archives. However, continuous modern observations of precipitation δ 18 O in many midlatitude regions, particularly in the coastal western United States, are sparse. Here, tree‐ring cellulose δ 18 O from southern California is used to assess the potential of this proxy as an indicator of long‐term hydroclimate and atmospheric variability. From 1954 to 2004, we observed that cellulose δ 18 O was well replicated within a single stand of blue oak ( Quercus douglasii ) on interannual and decadal time scales. By using a forward mechanistic model, we demonstrate that cellulose δ 18 O is not driven solely by the oxygen isotope composition of precipitation at the site nor any other single hydroclimate variable. Instead, the interannual variability in cellulose δ 18 O prior to 1979 is positively correlated with growing season soil water δ 18 O and after 1979 is negatively correlated with relative humidity. In addition, 2 years (1983 and 1998) of anomalously low cellulose δ 18 O coincided with the wettest years in California and the strongest El Niño events of the late 20th century. For these years, decreased near surface evaporation and/or increased upper‐level condensation could account for the more depleted cellulose δ 18 O values. While blue oak cellulose δ 18 O is sensitive to atmospheric and hydroclimate variability, the varying temporal correlation between the cellulose δ 18 O and different environmental variables complicates any attempt to use the cellulose oxygen isotopes for reconstructions of climate variability beyond the calibration period.

The content you want is available to Zendy users.

Already have an account? Click here to sign in.
Having issues? You can contact us here