Climatic Regionalization and the Spatio-Temporal Occurrence of Extreme Single-Year Drought Events (1500–1998) in the Interior Pacific Northwest, USA

AbstractTree-ring records from western juniper (Juniperus occidentalis var. occidentalis Hook.) growing throughout the interior Pacific Northwest identify extreme climatic pointer years (CPYs) (i.e., severe single-year droughts) from 1500–1998. Widespread and extreme CPYs were concentrated in the 16th and early part of the 17th centuries and did not occur again until the early 20th century. The 217-yr absence of extreme CPYs may have occurred during an extended period of low variance in the Pacific Decadal Oscillation. We mapped climatic boundaries for the interior Pacific Northwest based on the location of sites with similar precipitation variability indices. Three regions, the Northwest (based on chronologies from nine sites), the Southwest (four sites), and the East (five sites) were identified. Our results suggest that western juniper radial growth indices have substantial interannual variability within the northwestern range of the species (central Oregon), particularly when compared with western juniper growing in its eastern range (eastern Oregon, southeastern Idaho, and northern Nevada) and southwestern range (southern Oregon and northeast California). We suspect that the substantial differences in the variability of western juniper radial growth indices are linked to the influence of ENSO events on winter/spring precipitation amounts.

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Linking colonies to fisheries: Spatio-temporal overlap between common murres (Uria aalge) from Tatoosh Island and coastal gillnet fisheries in the Pacific Northwest, USA

Biological Conservation ◽

10.1016/j.biocon.2008.09.015 ◽

2008 ◽

Vol 141 (12) ◽

pp. 3101-3115 ◽

Cited By ~ 3

Author(s):

Nathalie J. Hamel ◽

Julia K. Parrish ◽

Jeff Laake

Keyword(s):

Pacific Northwest ◽

Uria Aalge ◽

The Pacific ◽

Common Murres ◽

Spatio Temporal ◽

Temporal Overlap

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Impacts of an Extreme Early-Season Freeze Event in the Interior Pacific Northwest (30 October–3 November 2002) on Western Juniper Woodlands

Journal of Applied Meteorology ◽

10.1175/jam2261.1 ◽

2005 ◽

Vol 44 (7) ◽

pp. 1152-1158 ◽

Cited By ~ 5

Author(s):

Paul A. Knapp ◽

Peter T. Soulé

Keyword(s):

Pacific Northwest ◽

Tree Mortality ◽

Extended Period ◽

Severe Drought ◽

Cold Spell ◽

Cold Event ◽

Western Juniper ◽

Synoptic Conditions ◽

Temperature Records

Abstract In mid-autumn 2002, an exceptional 5-day cold spell affected much of the interior Pacific Northwest, with minimum temperatures averaging 13°C below long-term means (1953–2002). On 31 October, minimum temperature records occurred at 98 of the 106 recording stations, with records lowered in some locations by 9°C. Calculation of recurrence intervals of minimum temperatures shows that 50% of the stations experienced a >500-yr event. The synoptic conditions responsible were the development of a pronounced high pressure ridge over western Canada and an intense low pressure area centered in the Intermountain West that promoted strong northeasterly winds. The cold spell occurred near the end of the growing season for an ecologically critical and dominant tree species of the interior Pacific Northwest—western juniper—and followed an extended period of severe drought. In spring 2003, it became apparent that the cold had caused high rates of tree mortality and canopy dieback in a species that is remarkable for its longevity and resistance to climatic stress. The cold event altered western juniper dominance in some areas, and this alteration may have long-term impacts on water budgets, fire intensities and frequencies, animal species interrelationships, and interspecific competition among plant species.

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The Lomatium grayi complex (Apiaceae) of the western United States: a taxonomic revision based on morphometric, essential oil composition, and larva-host coevolution studies

Journal of the Botanical Research Institute of Texas ◽

10.17348/jbrit.v12.i2.945 ◽

2018 ◽

Vol 12 (2) ◽

pp. 387-444

Author(s):

Jason Andrew Alexander ◽

Wayne Whaley ◽

Natalie Blain

Keyword(s):

Essential Oil ◽

Pacific Northwest ◽

Morphometric Analysis ◽

Taxonomic Revision ◽

Essential Oil Composition ◽

Herbarium Specimens ◽

Oil Composition ◽

Northern Nevada ◽

The Pacific ◽

Multiple Species

The Lomatium grayi complex is morphologically diverse across it range. The type species of this complex, Lomatium grayi s.s., has been found to not be a host of the larvae of Papilio indra, while the other three morphotypes are larval-hosts. A fifteen character, morphometric analysis was conducted on 390 herbarium specimens from throughout the range of this species. PCA, MANOVA, CDA, and Tukey tests revealed that the majority of the characters in this dataset were significantly different between four regional morphotypes. As a result of the morphometric analysis, the morphotypes are herein proposed as four species. Two new species are proposed for populations of L. grayi in the Pacific Northwest. Lomatium papilioniferum is proposed for plants in California, western Idaho, northern Nevada, Oregon, and Washington. Lomatium klickitatense is proposed for populations of robust plants from western Klickitat County, Washington, and northern Hood River County, Oregon. Lomatium grayi var. depauperatum is elevated to a species. This leaves no infraspecific taxa within L. grayi s.s. A presence/absence phenetic analysis of combined essential oil data was inconclusive regarding the composition of L. grayi s.s., which was found to be more similar to Lomatium klickitatense and Lomatium depauperatum than other species of Lomatium. Taxonomic treatments for each of the four species in this complex are provided. A key to these species and the multiple species that have been commonly mistaken for L. grayi is also included.

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A spatial analysis of fine-root biomass from stand data in the Pacific Northwest

Canadian Journal of Forest Research ◽

10.1139/x04-098 ◽

2004 ◽

Vol 34 (10) ◽

pp. 2169-2180 ◽

Cited By ~ 4

Author(s):

E Henry Lee ◽

David T Tingey ◽

Peter A Beedlow ◽

Mark G Johnson ◽

Robert B McKane

Keyword(s):

Pacific Northwest ◽

Root Biomass ◽

Fine Root ◽

Sampling Technique ◽

Fine Root Biomass ◽

Western Juniper ◽

Accuracy And Precision ◽

The Pacific ◽

Additive Contribution ◽

Tree Metrics

High spatial variability of fine roots in natural forest stands makes accurate estimates of stand-level fine-root biomass difficult and expensive to obtain by standard coring methods. This study uses aboveground tree metrics and spatial relationships to improve core-based estimates of stand-level fine-root biomass. Using the multiple-tree Ribbens model for pure stands, the approach assumes that the total fine-root biomass at a given point is the additive contribution of the nearest dominant trees and that fine-root biomass for a single tree depends on the distance to the trunk and its size. A Monte Carlo random sampling technique, or sampling on a regular grid, is used to estimate the average fine-root biomass across the stand. We illustrate the applicability of this approach by using it on root-core data from a Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stand and a western juniper (Juniperus occidentalis Hook.) stand in the Pacific Northwest. We conclude that stand-level fine-root biomass is adequately estimated using the Ribbens model. Unlike the model-based estimate for stand-level fine-root biomass, the accuracy and precision of the arithmetic mean of the coring samples depends on the spatial heterogeneity of root distributions and the representativeness of the root coring samples.

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Spatio-Temporal Characterization of Pinniped Strandings and Human Interaction Cases in the Pacific Northwest, 1991-2016

Aquatic Mammals ◽

10.1578/am.44.3.2018.299 ◽

2018 ◽

Vol 44 (3) ◽

pp. 299-318 ◽

Cited By ~ 4

Author(s):

Amanda J. Warlick ◽

Deborah A. Duffield ◽

Dyanna M. Lambourn ◽

Steven J. Jeffries ◽

James M. Rice ◽

...

Keyword(s):

Pacific Northwest ◽

Human Interaction ◽

The Pacific ◽

Spatio Temporal

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Cryptococcus deuterogattii VGIIa infection associated with travel to the Pacific Northwest outbreak region in an anti-GM-CSF autoantibody positive patient in the United States

10.1101/493239 ◽

2019 ◽

Author(s):

Shelly Applen Clancey ◽

Emily J. Ciccone ◽

Marco A. Coelho ◽

Joie Davis ◽

Li Ding ◽

...

Keyword(s):

United States ◽

Risk Factor ◽

Pacific Northwest ◽

Extended Period ◽

The United States ◽

International Travel ◽

Gm Csf ◽

First Case ◽

The Pacific ◽

Magnetic Resonance Imaging Mri

AbstractThe Pacific Northwest (PNW), Vancouver Island, Oregon, and Washington have been the location of an ongoing Cryptococcus gattii outbreak since the 1990s, and there is evidence that the outbreak is expanding along the West Coast into California. Here we report a clinical case of a 69-year-old, HIV-negative man from North Carolina who was diagnosed with a fungal brain mass by magnetic resonance imaging (MRI) and pathology. He had traveled to Seattle and Vancouver three years earlier and Costa Rica four months prior to presentation. Phenotypic evidence shows the fungal mass isolated from the patient’s brain is C. gattii. In agreement with the phenotypic results, MLST provides genotypic evidence that assigns the infecting organism within in the C. gattii species complex and belonging to the C. deuterogattii VGIIa clade. Whole genome sequencing revealed >99.99% identity to the C. deuterogattii reference strain R265, indicating that the infecting strain is derived from the highly clonal outbreak strains in the PNW. We conclude the patient acquired the C. gattii infection during his travel to region three years prior and the infection was dormant for an extended period of time before causing disease. The patient tested positive for anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) autoantibodies, supporting earlier reports that implicate these autoantibodies as a risk factor a risk factor associated with C. gattii infection.ImportanceMortality rates associated with C. gattii infections are estimated to be between 13% and 33% depending on an individual’s predisposition, and C. gattii has caused more at least 39 deaths in the PNW region. There have been four other international travel cases reported in patients from Europe and Asia with travel history to the PNW, but this study describes the first North American travel who acquired C. deuterogattii infection presenting within the United States, and the first case of a C. deuterogattii outbreak infection associated with anti-GM-CSF autoantibodies. Early and accurate diagnoses are important for disease prevention, treatment, and control of infectious diseases. Continual reporting of C. deuterogattii infections is necessary to raise awareness of the ongoing outbreak in the PNW and alert travelers and physicians to the endemic areas with potential risks.

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