Potential effects of ozone, climate, and spruce budworm on Douglas-fir growth in the Wasatch Mountains

David J Wager; F A Baker

doi:10.1139/x02-211

Potential effects of ozone, climate, and spruce budworm on Douglas-fir growth in the Wasatch Mountains

Canadian Journal of Forest Research ◽

10.1139/x02-211 ◽

2003 ◽

Vol 33 (5) ◽

pp. 910-921 ◽

Cited By ~ 5

Author(s):

David J Wager ◽

F A Baker

Keyword(s):

Fungal Pathogens ◽

Salt Lake ◽

Negative Relationship ◽

Douglas Fir ◽

Spring Precipitation ◽

Salt Lake Valley ◽

Ozone Concentrations ◽

Wasatch Mountains ◽

Ozone Injury ◽

Bear River

This study assessed the potential for ozone injury to vegetation in the central Wasatch Mountains of Utah by determining if Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) experienced reduced growth since the onset of high ozone concentrations. Dendrochronological techniques were used to model Douglas-fir growth in six central Wasatch Mountain stands, where ozone concentrations suggest the possibility of injury to vegetation, and in four Bear River stands, where ozone concentrations are lower than injury thresholds. Previous-year growth, temperature, and Palmer's Z index variables explained 5370% of the variance in annual growth. Reduced Douglas-fir growth, not explained by the model or insect and disease records, occurred after 1970 in the central Wasatch Mountains but not in the Bear River Mountains. Douglas-fir growth in the central Wasatch Mountains was slightly negatively correlated with the previous-year ozone concentrations in nearby Salt Lake valley. Between 1962 and 1973, a fluctuating budworm population due to varying spring precipitation was suggested to have replaced precipitation as the factor limiting tree growth, causing an anomalous negative relationship between precipitation and Douglas-fir growth. Because of a suite of possible factors (e.g., undetected climatic variables, fungal pathogens, competitive interactions) influencing Douglas-fir growth, ozone may be one factor in a larger stressor complex reducing growth.

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Techniques, analysis, and noise in a Salt Lake Valley 4D gravity experiment

Geophysics ◽

10.1190/1.2996303 ◽

2008 ◽

Vol 73 (6) ◽

pp. WA71-WA82 ◽

Cited By ~ 19

Author(s):

Paul Gettings ◽

David S. Chapman ◽

Rick Allis

Keyword(s):

Salt Lake ◽

Water Levels ◽

Reference Station ◽

Salt Lake Valley ◽

Wasatch Mountains ◽

Gravity Measurements ◽

Elevation Changes ◽

Induced Changes ◽

Irrigation Effects ◽

East West

Repeated high-precision gravity measurements using an automated gravimeter and analysis of time series of [Formula: see text] samples allowed gravity measurements to be made with an accuracy of [Formula: see text] or better. Nonlinear instrument drift was removed using a new empirical staircase function built from multiple station loops. The new technique was developed between March 1999 and September 2000 in a pilot study conducted in the southern Salt Lake Valley along an east-west profile of eight stations from the Wasatch Mountains to the Jordan River. Gravity changes at eight profile stations were referenced to a set of five stations in the northern Salt Lake Valley, which showed residual signals of [Formula: see text] in amplitude, assuming a reference station near the Great Salt Lake to be stable. Referenced changes showed maximum amplitudes of [Formula: see text] through [Formula: see text] at profile stations, with minima in summer 1999, maxima in winter 1999–2000, and some decrease through summer 2000. Gravity signals were likely a composite of production-induced changes monitored by well-water levels, elevation changes, precipitation-induced vadose-zone changes, and local irrigation effects for which magnitudes were estimated quantitatively.

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Impact of Lake Breezes on Summer Ozone Concentrations in the Salt Lake Valley

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-16-0216.1 ◽

2017 ◽

Vol 56 (2) ◽

pp. 353-370 ◽

Cited By ~ 21

Author(s):

Brian K. Blaylock ◽

John D. Horel ◽

Erik T. Crosman

Keyword(s):

Salt Lake ◽

Quality Measurement ◽

Urban Canopy ◽

Lake Breeze ◽

Model Errors ◽

Mobile Platforms ◽

Salt Lake Valley ◽

Ozone Concentrations ◽

Northern Utah ◽

Passive Tracers

AbstractDuring the late afternoon of 18 June 2015, ozone concentrations in advance of a strong lake-breeze front arising from the Great Salt Lake in northern Utah were ~20 ppb lower than those in its wake. The lake-breeze progression and ozone concentrations in the valley were monitored by an enhanced observation network that included automated weather stations, a nearby Terminal Doppler Weather Radar, state air quality measurement sites, and mobile platforms, including a news helicopter. Southerly flow opposing the lake breeze increased convergent frontogenesis and delayed the onset of its passage through the Salt Lake valley. Ozone concentrations were exceptionally high aloft at the lake-breeze frontal boundary. The progression of this lake breeze was simulated using the Weather Research and Forecasting Model at 1-km horizontal grid spacing over northern Utah. The model was initialized using hourly analyses from the High Resolution Rapid Refresh model. Errors in the underlying surface initialization were improved by adjusting the areal extent and surface temperature of the lake to observed lake conditions. An urban canopy parameterization is also included. The opposing southerly flow was weaker in the simulation than that observed such that the simulated lake-breeze front occurred too early. Continuous passive tracers initialized within and ahead of the lake breeze highlight the dispersion and transport of pollutants arising from the lake-breeze front. Tracers within the lake breeze are confined near the surface while tracers in advance of the front are lofted over it.

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Orographic Influences on a Great Salt Lake–Effect Snowstorm

Monthly Weather Review ◽

10.1175/mwr-d-12-00328.1 ◽

2013 ◽

Vol 141 (7) ◽

pp. 2432-2450 ◽

Cited By ~ 40

Author(s):

Trevor I. Alcott ◽

W. James Steenburgh

Keyword(s):

Snow Water Equivalent ◽

Salt Lake ◽

Great Salt Lake ◽

Salt Lake Valley ◽

Wasatch Mountains ◽

Lake Effect ◽

Thermally Driven ◽

Precipitation Band ◽

Northern Utah ◽

Snow Water

Abstract Although several mountain ranges surround the Great Salt Lake (GSL) of northern Utah, the extent to which orography modifies GSL-effect precipitation remains largely unknown. Here the authors use observational and numerical modeling approaches to examine the influence of orography on the GSL-effect snowstorm of 27 October 2010, which generated 6–10 mm of precipitation (snow-water equivalent) in the Salt Lake Valley and up to 30 cm of snow in the Wasatch Mountains. The authors find that the primary orographic influences on the event are 1) foehnlike flow over the upstream orography that warms and dries the incipient low-level air mass and reduces precipitation coverage and intensity; 2) orographically forced convergence that extends downstream from the upstream orography, is enhanced by blocking windward of the Promontory Mountains, and affects the structure and evolution of the lake-effect precipitation band; and 3) blocking by the Wasatch and Oquirrh Mountains, which funnels the flow into the Salt Lake Valley, reinforces the thermally driven convergence generated by the GSL, and strongly enhances precipitation. The latter represents a synergistic interaction between lake and downstream orographic processes that is crucial for precipitation development, with a dramatic decrease in precipitation intensity and coverage evident in simulations in which either the lake or the orography are removed. These results help elucidate the spectrum of lake–orographic processes that contribute to lake-effect events and may be broadly applicable to other regions where lake effect precipitation occurs in proximity to complex terrain.

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