Use of atmospheric CO2-sensitive trees may influence dendroclimatic reconstructions

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Paul A. Knapp, Professor (Creator)
The University of North Carolina at Greensboro (UNCG )
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Abstract: We examined recent radial growth increases in western juniper trees using an 11-site chronology dating from AD 1000-2006. By various measures, radial growth during the late 20th/early 21st centuries was exceptional, with increases occurring absent of regional climatic change. We found that 54% of annual radial growth variability was explained by June Palmer Drought Severity Index (PDSI) values, but the inclusion of atmospheric CO2 values accounted for a 14% increase in explanatory power. We reconstructed June PDSI both including and excluding CO2, and found that PDSI values were overestimated at the end of the record with CO2 omitted from the model. We conclude that: 1) western juniper radial growth was associated with rising CO2 during the late 20th/early 21st centuries; and, 2) the use of CO2-sensitive trees such as western juniper for dendroclimatic reconstructions may influence the results if the impacts of CO2 fertilization are omitted

Additional Information

Geophysical Research Letters
Language: English
Date: 2008
western juniper trees, dendroclimatic reconstructions, Geography , Atmospheric Composition and Structure: Aerosols and particles (0345, 4801, 4906), Atmospheric Processes: Climate change and variability (1616, 1635, 3309, 4215, 4513), Atmospheric Processes: Model calibration (1846)

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