Reconstructing Summer Upper-Level Flow In The Northern Rocky Mountains Using An Alpine Larch (Larix Lyallii) Tree-Ring Chronology
- ASU Author/Contributor (non-ASU co-authors, if there are any, appear on document)
- Evan E. Montpellier (Creator)
- Institution
- Appalachian State University (ASU )
- Web Site: https://library.appstate.edu/
- Advisor
- Peter T. Soule
Abstract: Mid-latitude mesoscale weather in the climatological summer is heavily influenced by fluctuations in synoptic-scale circulation patterns. Previous research has linked Arctic amplification to alterations in summer synoptic climatology, leading to more extreme weather events in the mid-latitudes. In this study we reconstruct seasonal (JJA) upper-level (500 hPa) atmospheric flow for four geographic locations in the mid-latitudes using an alpine larch (Larix lyallii Parl.) tree-ring chronology derived from western Montana. Our goal is to assess the long-term (400+ year) stability of upper-level flow to place the observed trends in a historical context. Spatial pattern correlations indicate that tree growth increases when meridional flow and zonal flow are strong west (r = 0.504, p = 0.001, n = 37) and north (r = 0.642, p < 0.001, n = 37) of the study site, respectively. Tree growth declines when meridional flow and zonal flow are strong east (r = -0.497, p = 0.001, n = 37) and south (r = -0.584, p < 0.001, n = 37) of the study site, respectively. Our 444-year climate reconstructions of 500 hPa flow show that ridging is becoming more intense in recent decades while troughs are declining in intensity.
Reconstructing Summer Upper-Level Flow In The Northern Rocky Mountains Using An Alpine Larch (Larix Lyallii) Tree-Ring Chronology
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Created on 5/17/2018
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Additional Information
- Publication
- Thesis
- Montpellier, E. (2018). "Reconstructing Summer Upper-Level Flow In The Northern Rocky Mountains Using An Alpine Larch (Larix Lyallii) Tree-Ring Chronology." Unpublished Master’s Thesis. Appalachian State University, Boone, NC.
- Language: English
- Date: 2018
- Keywords
- Tree-ring research, Climate reconstruction,
Arctic amplification, Upper-level flow,
Western Montana