|Analyses of Intrinsic Water-Use Efficiency Indicate Performance Differences of Ponderosa Pine and Douglas-fir in Response to CO2 Enrichment
||Aim: Increasing intrinsic water-use efficiency (iWUE) in trees is a global-scale response to increasing levels of atmospheric carbon dioxide (Ca). Our primary goal was to determine whether significant differences in either iWUE or radial growth exist...
|Human Agency, Environmental Drivers, and Western Juniper Establishment During the Late Holocene
||Western juniper (Juniperus occidentalis var. occidentalis) is undergoing rapid rates of expansion, and human activities (domestic livestock grazing, fire suppression) are typically presented as the primary agents of change. To determine the importanc...
|Impacts of an extreme early-season freeze event in the Interior Pacific Northwest (30 October-3 November 2002) on Western juniper woodlands
||In mid-autumn 2002, an exceptional 5-day cold spell affected much of the interior Pacific Northwest, with minimum temperatures averaging 13[degree]C below long-term means (1953-21)112). On 31 October, minimum temperature records occurred at 98 of the...
|Impacts of Human Disturbance on the Temporal Stability of Climate–Growth Relationships in a Red Spruce Forest, Southern Appalachian Mountains, USA
||We used dendrochronological techniques to develop a tree-ring chronology (AD 1874–2009) from live trees and investigated the temporal stability of regional climate signals in the heavily disturbed red spruce (Picea rubens Sarg.) and Fraser fir [Abies...
|P.A. Knapp and P.T. Soulé. (2008) "Use of Atmospheric CO2-sensitive Trees May Influence Dendroclimatic REconstructions." Geophysical Research Letters. 35(24) Doi: 10.1029/2008GL035664. Published by American Geophysical Union
|| 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...
|Post-drought Growth Response of Western Juniper (Juniperus occidentalis var. occidentalis) in Central Oregon
||Increased atmospheric CO2 may affect the physiological response of natural trees to drought. We examined radial growth rates developed from five western juniper chronologies to determine if post-drought growth responses have changed. Using prior year...
|Trends in mid-latitude cyclone frequency and occurrence during fire season in the Northern Rockies: 1900-2004.
||We examined changes in the timing and frequency of major midlatitude cyclones (MLCs) during August through October for eight climate stations in the Northern Rockies from 1900-2004. As MLCs can effectively diminish fire activity through both cooler t...