Journal articles: 'Salt Lake Valley'

1

Zumpfe, Daniel E., and John D. Horel. "Lake-Breeze Fronts in the Salt Lake Valley." Journal of Applied Meteorology and Climatology 46, no. 2 (February 1, 2007): 196–211. http://dx.doi.org/10.1175/jam2449.1.

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Abstract Winds at the Salt Lake City International Airport (SLC) during the April–October period from 1948 to 2003 have been observed to shift to the north (up-valley direction) between late morning and afternoon on over 70% of the days without precipitation. Lake-breeze fronts that develop as a result of the differential heating between the air over the nearby Great Salt Lake and that over the lake’s surroundings are observed at SLC only a few times each month. Fewer lake-breeze fronts are observed during late July–early September than before or after that period. Interannual fluctuations in the areal extent of the shallow Great Salt Lake contribute to year-to-year variations in the number of lake-breeze frontal passages at SLC. Data collected during the Vertical Transport and Mixing Experiment (VTMX) of October 2000 are used to examine the structure and evolution of a lake-breeze front that moved through the Salt Lake Valley on 17 October. The onset of upslope and up-valley winds occurred within the valley prior to the passage of the lake-breeze front. The lake-breeze front moved at roughly 3 m s−1 up the valley and was characterized near the surface by an abrupt increase in wind speed and dewpoint temperature over a distance of 3–4 km. Rapid vertical mixing of aerosols at the top of the 600–800-m-deep boundary layer was evident as the front passed.

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2

Hooke, Roger LeB. "Lake Manly(?) Shorelines in the Eastern Mojave Desert, California." Quaternary Research 52, no. 3 (November 1999): 328–36. http://dx.doi.org/10.1006/qres.1999.2080.

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Near Mesquite Spring on the southern edge of the Soda Lake basin in the Mojave Desert, there is a shoreline of an ancient lake at an elevation of 340 m above sea level. At present, Soda Lake would overflow at 280 m; a lake surface at 340 m would extend ∼240 km northward, to the northern end of Death Valley. Shorelines and lacustrine deposits near the Salt Spring and Saddle Peak Hills, 75 km north of Mesquite Spring, are at ∼180 m; a lake surface at this elevation today would also extend to the northern end of Death Valley. The most prominent shoreline of the pluvial lake that occupied Death Valley during the Pleistocene, Lake Manly, is that of the Blackwelder stand which ended ∼120,000 yr ago. This shoreline is ∼90 m above sea level. The Mesquite Spring and Salt Spring Hills shorelines were probably formed by the Blackwelder stand and subsequently displaced with respect to one another, tectonically, due to transpression in the northeastern Mojave Desert and NW–SE extension across Death Valley. This tectonic regime would result in subsidence of Death Valley and the Salt Spring Hills relative to Mesquite Spring. A reconstruction suggests that the topography at the time of the Blackwelder stand would have had a sill near the level of the highest lake, and also one ∼20 m lower, corresponding to the next most prominent shoreline in Death Valley. Expansion of the lake over these sills would have increased evaporation, thus possibly stabilizing the lake level.

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Olsen, Michael J., Steven F. Bartlett, and Barry J. Solomon. "Lateral Spread Hazard Mapping of the Northern Salt Lake Valley, Utah, for a M7.0 Scenario Earthquake." Earthquake Spectra 23, no. 1 (February 2007): 95–113. http://dx.doi.org/10.1193/1.2424987.

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This paper describes the methodology used to develop a lateral spread-displacement hazard map for northern Salt Lake Valley, Utah, using a scenario M7.0 earthquake occurring on the Salt Lake City segment of the Wasatch fault. The mapping effort is supported by a substantial amount of geotechnical, geologic, and topographic data compiled for the Salt Lake Valley, Utah. ArcGIS® routines created for the mapping project then input this information to perform site-specific lateral spread analyses using methods developed by Bartlett and Youd (1992) and Youd et. al. (2002) at individual borehole locations. The distributions of predicted lateral spread displacements from the boreholes located spatially within a geologic unit were subsequently used to map the hazard for that particular unit. The mapped displacement zones consist of low hazard (0–0.1 m), moderate hazard (0.1–0.3 m), high hazard (0.3–1.0 m), and very high hazard (>1.0 m). As expected, the produced map shows the highest hazard in the alluvial deposits at the center of the valley and in sandy deposits close to the fault. This mapping effort is currently being applied to the southern part of the Salt Lake Valley, Utah, and probabilistic maps are being developed for the entire valley.

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Moravek, Alexander, Jennifer G. Murphy, Amy Hrdina, John C. Lin, Christopher Pennell, Alessandro Franchin, Ann M. Middlebrook, et al. "Wintertime spatial distribution of ammonia and its emission sources in the Great Salt Lake region." Atmospheric Chemistry and Physics 19, no. 24 (December 20, 2019): 15691–709. http://dx.doi.org/10.5194/acp-19-15691-2019.

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Abstract. Ammonium-containing aerosols are a major component of wintertime air pollution in many densely populated regions around the world. Especially in mountain basins, the formation of persistent cold-air pools (PCAPs) can enhance particulate matter with diameters less than 2.5 µm (PM2.5) to levels above air quality standards. Under these conditions, PM2.5 in the Great Salt Lake region of northern Utah has been shown to be primarily composed of ammonium nitrate; however, its formation processes and sources of its precursors are not fully understood. Hence, it is key to understanding the emission sources of its gas phase precursor, ammonia (NH3). To investigate the formation of ammonium nitrate, a suite of trace gases and aerosol composition were sampled from the NOAA Twin Otter aircraft during the Utah Winter Fine Particulate Study (UWFPS) in January and February 2017. NH3 was measured using a quantum cascade tunable infrared laser differential absorption spectrometer (QC-TILDAS), while aerosol composition, including particulate ammonium (pNH4), was measured with an aerosol mass spectrometer (AMS). The origin of the sampled air masses was investigated using the Stochastic Time-Inverted Lagrangian Transport (STILT) model and combined with an NH3 emission inventory to obtain model-predicted NHx (=NH3+pNH4) enhancements. Enhancements represent the increase in NH3 mixing ratios within the last 24 h due to emissions within the model footprint. Comparison of these NHx enhancements with measured NHx from the Twin Otter shows that modelled values are a factor of 1.6 to 4.4 lower for the three major valleys in the region. Among these, the underestimation is largest for Cache Valley, an area with intensive agricultural activities. We find that one explanation for the underestimation of wintertime emissions may be the seasonality factors applied to NH3 emissions from livestock. An investigation of inter-valley exchange revealed that transport of NH3 between major valleys was limited and PM2.5 in Salt Lake Valley (the most densely populated area in Utah) was not significantly impacted by NH3 from the agricultural areas in Cache Valley. We found that in Salt Lake Valley around two thirds of NHx originated within the valley, while about 30 % originated from mobile sources and 60 % from area source emissions in the region. For Cache Valley, a large fraction of NOx potentially leading to PM2.5 formation may not be locally emitted but mixed in from other counties.

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Medioli, Barbara E., Aruna Dixit, John P. Smol, Thane W. Anderson, and Susan M. Burbidge. "Paleolimnological Evidence of Terrestrial and Lacustrine Environmental Change in Response to European Settlement of the Red River Valley, Manitoba and North Dakota*." Paleoenvironments 59, no. 2-3 (April 4, 2007): 263–75. http://dx.doi.org/10.7202/014756ar.

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Abstract Limnological and terrestrial changes in three floodplain lakes are correlated with settlement of the Red River valley in Manitoba and North Dakota. Distinctive pollen, diatom and thecamoebian assemblages provide proxy evidence of the ecological changes from pre- to post-settlement periods in Horseshoe Lake, Lake Louise and Salt Lake. In the pre-settlement period (Zone I), prior to ~1812, grass and Quercus pollen dominate and are indicative of a tall grass prairie-oak riparian forest ecosystem. Diatom and thecamoebian assemblages suggest oligo- to mesotrophic limnological conditions, and more brackish water than presently occurs in Horseshoe Lake. The onset of the post-settlement period (Zone II) corresponds to distinctive terrestrial and limnological changes. A sharp decline in Quercus at the base of this zone correlates with documented regional riparian deforestation, whereas the increase in the weed taxa Salsola, Brassica, Rumex and Ambrosia is associated with the introduction of European agricultural practices and cereal grasses. Diatom and thecamoebian assemblages indicate progressive floodplain lake eutrophication, as well as increased salinity in Salt Lake. Salt Lake is the most brackish lake and supports the brackish-water foraminifera Trochammina macrescens cf. polystoma. Increased erosion and run off in the watershed has caused a more than twofold increase in lake basin sedimentation between the pre-settlement and post-settlement periods.

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Blaylock, Brian K., John D. Horel, and Erik T. Crosman. "Impact of Lake Breezes on Summer Ozone Concentrations in the Salt Lake Valley." Journal of Applied Meteorology and Climatology 56, no. 2 (February 2017): 353–70. http://dx.doi.org/10.1175/jamc-d-16-0216.1.

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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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7

Afzal, Shahzad, Mohammad Younas, and Khadim Hussain. "Selenium Speciation of Surface Sediments from Saline Lakes of the Soan-Sakesar Valley Salt-Range, Pakistan." Water Quality Research Journal 34, no. 4 (November 1, 1999): 575–88. http://dx.doi.org/10.2166/wqrj.1999.029.

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Abstract The chemical species of selenium from the surface sediments from three eutroph-ic lakes of the Soan-Sakesar Valley were examined. The major objectives of the study were to examine the oxidation states of selenium in the lake sediments. The following selenium concentrations were observed from lakes Uchhali, Khabbaki and Jahlar, respectively: total selenium: 4.03, 1.55 and 1.4 mg/kg; Se+VI: 0.86, 0.39 and 0.31 mg/kg; Se+IV: 0.95, 0.27 and 0.25 mg/kg; Se-II:1.15, 0.45 and 0.33; and Se0: 1.17, 0.48 and 0.53 mg/kg. Lake sediments have higher nitrogen (0.04—0.35% of dry weight) and phosphorus (0.04—0.29% of dry weight) levels due to agriculture drainage water and sewage waste from small villages. X-ray diffraction analysis has shown that albite, calcite, chlorite, illite and quartz minerals were present in the sediments of lakes Uchhali, Khabbaki and Jahlar. Kaolinite was present only in lakes Uchhali and Khabbaki and goethite only in Lake Uchhali. Linear relationships were observed between selenium fractions, and minerals present in these lakes point out the phenomena of adsorption on the surface of these minerals. The organic C contents of 2.2, 2.8 and 3.1% dry weight in lakes Uchhali, Khabbaki and Jahlar, respectively, show linear relationships with Se-II, Se0 and total selenium. It suggests that Se in the sediments is highly associated with the sediment organic fraction. The results indicate that nutrient loads and organic C are responsible for the high microbial activity, which reduces sele-nates to more insoluble Se species in the lake sediments.

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8

Gharbi, A., and R. C. Peralta. "Integrated embedding optimization applied to Salt Lake valley aquifers." Water Resources Research 30, no. 3 (March 1994): 817–32. http://dx.doi.org/10.1029/93wr03349.

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9

Yeager, Kristen N., W. James Steenburgh, and Trevor I. Alcott. "Contributions of Lake-Effect Periods to the Cool-Season Hydroclimate of the Great Salt Lake Basin." Journal of Applied Meteorology and Climatology 52, no. 2 (February 2013): 341–62. http://dx.doi.org/10.1175/jamc-d-12-077.1.

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AbstractAlthough smaller lakes are known to produce lake-effect precipitation, their influence on the precipitation climatology of lake-effect regions remains poorly documented. This study examines the contribution of lake-effect periods (LEPs) to the 1998–2009 cool-season (16 September–15 May) hydroclimate in the region surrounding the Great Salt Lake, a meso-β-scale hypersaline lake in northern Utah. LEPs are identified subjectively from radar imagery, with precipitation (snow water equivalent) quantified through the disaggregation of daily (i.e., 24 h) Cooperative Observer Program (COOP) and Snowpack Telemetry (SNOTEL) observations using radar-derived precipitation estimates. An evaluation at valley and mountain stations with reliable hourly precipitation gauge observations demonstrates that the disaggregation method works well for estimating precipitation during LEPs. During the study period, LEPs account for up to 8.4% of the total cool-season precipitation in the Great Salt Lake basin, with the largest contribution to the south and east of the Great Salt Lake. The mean monthly distribution of LEP precipitation is bimodal, with a primary maximum from October to November and a secondary maximum from March to April. LEP precipitation is highly variable between cool seasons and is strongly influenced by a small number of intense events. For example, at a lowland (mountain) station in the lake-effect-precipitation belt southeast of the Great Salt Lake, just 12 (13) events produce 50% of the LEP precipitation. Although these results suggest that LEPs contribute modestly to the hydroclimate of the Great Salt Lake basin, infrequent but intense events have a profound impact during some cool seasons.

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10

Alcott, Trevor I., and W. James Steenburgh. "Orographic Influences on a Great Salt Lake–Effect Snowstorm." Monthly Weather Review 141, no. 7 (July 1, 2013): 2432–50. http://dx.doi.org/10.1175/mwr-d-12-00328.1.

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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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Ku, Teh-Lung, Shangde Luo, Tim K. Lowenstein, Jianren Li, and Ronald J. Spencer. "U-Series Chronology of Lacustrine Deposits in Death Valley, California." Quaternary Research 50, no. 3 (November 1998): 261–75. http://dx.doi.org/10.1006/qres.1998.1995.

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Uranium-series dating on a 186-m core (DV93-1) drilled from Badwater Basin in Death Valley, California, and on calcareous tufas from nearby strandlines shows that Lake Manly, the lake that periodically flooded Death Valley during the late Pleistocene, experienced large fluctuations in depth and chemistry over the last 200,000 yr. Death Valley has been occupied by a long-standing deep lake, perennial shallow saline lakes, and a desiccated salt pan similar to the modern valley floor. The average sedimentation rate of about 1 mm/yr for core DV93-1 was punctuated by episodes of more-rapid accumulation of halite. Arid conditions similar to the modern conditions prevailed during the entire Holocene and between 120,000 and 60,000 yr B.P. From 35,000 yr B.P. to the beginning of the Holocene, a perennial saline lake existed, over 70 m at its deepest. A much deeper and longer lasting perennial Lake Manly existed from about 185,000 to 128,000 yr B.P., with water depths reaching about 175 m, if not 330 m. This lake had two significant “dry” excursions of 102–103yr duration about 166,000 and 146,000 yr B.P., and it began to shrink to the point of halite precipitation between 128,000 and 120,000 yr B.P. The two perennial lake periods correspond to marine oxygen isotopic stages (OIS) 2 and 6. Based on the shoreline tufa ages, we do not rule out the possible existence ∼200,000 yr ago of yet a third perennial lake comparable in size to the OIS 6 lake. The234U/238U data suggest that U in tufa owes its origin mainly to Ca-rich springs fed by groundwater that emanated along lake shorelines in southern Death Valley, and that an increase of this spring-water input relative to the river-water input apparently occurred during OIS 6.

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Fast, Jerome D., K. Jerry Allwine, Russell N. Dietz, Kirk L. Clawson, and Joel C. Torcolini. "Dispersion of Perfluorocarbon Tracers within the Salt Lake Valley during VTMX 2000." Journal of Applied Meteorology and Climatology 45, no. 6 (June 1, 2006): 793–812. http://dx.doi.org/10.1175/jam2371.1.

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Abstract Six perfluorocarbon tracer experiments were conducted in Salt Lake City, Utah, during October 2000 as part of the Vertical Transport and Mixing (VTMX) field campaign. Four tracers were released at different sites to obtain information on dispersion during stable conditions within down-valley flow, canyon outflow, and interacting circulations in the downtown area. Some of the extensive tracer data that were collected are presented in the context of the meteorological field campaign measurements. Tracer measurements at building-top sites in the downtown area and along the lower slopes of the Wasatch Front indicated that vertical mixing processes transported material up to at least 180 m above the valley floor, although model simulations suggest that tracers were transported upward to much higher elevations. Tracer data provided evidence of downward mixing of canyon outflow, upward mixing within down-valley flow, horizontal transport above the surface stable layer, and transport within horizontal eddies produced by the interaction of canyon and down-valley flows. Although point meteorological measurements are useful in evaluating the forecasts produced by mesoscale models, the tracer data provide valuable information on how the time-varying three-dimensional mean and turbulent motions over urban and valley spatial scales affect dispersion. Although the mean tracer transport predicted by the modeling system employed in this study was qualitatively similar to the measurements, improvements are needed in the treatment of turbulent vertical mixing.

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Gettings, Paul, David S. Chapman, and Rick Allis. "Techniques, analysis, and noise in a Salt Lake Valley 4D gravity experiment." GEOPHYSICS 73, no. 6 (November 2008): WA71—WA82. http://dx.doi.org/10.1190/1.2996303.

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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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Yang, Wenbo, H. Roy Krouse, Ronald J. Spencer, Tim K. Lowenstein, Ian E. Hutcheon, Teh-Lung Ku, Jianren Li, Sheila M. Roberts, and Christopher B. Brown. "A 200,000-Year Record of Change in Oxygen Isotope Composition of Sulfate in a Saline Sediment Core, Death Valley, California." Quaternary Research 51, no. 2 (March 1999): 148–57. http://dx.doi.org/10.1006/qres.1998.2022.

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Abstractδ18O values of sulfate minerals from a 186-m core (past 200,000 years) in Death Valley varied from +9 to +23‰ (V-SMOW). Sulfates that accumulated in the past ephemeral saline lake, salt pans, and mud flats have relatively low δ18O values similar to those of present-day local inflows. Sulfates that accumulated during two perennial lake intervals, however, have higher δ18O values, reflecting changes in temperature, lake water levels, and/or sulfur redox reactions. Over the same time interval, the δ18O record for sulfate had excursions that bear similarities to those found for carbonate in the Death Valley core, marine carbonate (SPECMAP), and polar ice in the Summit ice core, Greenland. The δ18O record differed considerably from the records reported for carbonate at Owens Lake and Devils Hole, which probably relates to different water sources. Death Valley, Owens Lake, and Devils Hole are responding to the same climatic changes but manifesting them differently. In Death Valley sediments, the isotopic composition of sulfate may have potential as an indicator of paleoenvironmental changes.

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Hu, Xie, Zhong Lu, and Teng Wang. "Characterization of Hydrogeological Properties in Salt Lake Valley, Utah, using InSAR." Journal of Geophysical Research: Earth Surface 123, no. 6 (June 2018): 1257–71. http://dx.doi.org/10.1029/2017jf004497.

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Crosman, Erik T., and John D. Horel. "Large-eddy simulations of a Salt Lake Valley cold-air pool." Atmospheric Research 193 (September 2017): 10–25. http://dx.doi.org/10.1016/j.atmosres.2017.04.010.

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Hu, Xie, and Roland Bürgmann. "Aquifer deformation and active faulting in Salt Lake Valley, Utah, USA." Earth and Planetary Science Letters 547 (October 2020): 116471. http://dx.doi.org/10.1016/j.epsl.2020.116471.

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Winsor, Kelsey, Kate M. Swanger, Esther L. Babcock, James L. Dickson, Rachel D. Valletta, and Daniel F. Schmidt. "Origin, structure and geochemistry of a rock glacier near Don Juan Pond, Wright Valley, Antarctica." Antarctic Science 32, no. 4 (March 11, 2020): 273–87. http://dx.doi.org/10.1017/s0954102020000139.

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AbstractThe South Fork of Wright Valley contains one of the largest rock glaciers in the McMurdo Dry Valleys, Antarctica, stretching 7 km from the eastern boundary of the Labyrinth and terminating at Don Juan Pond (DJP). Here, we use results from ground-penetrating radar (GPR), qualitative field observations, soil leaching analyses and X-ray diffraction analyses to investigate rock glacier development. The absence of significant clean ice in GPR data, paired with observations of talus and interstitial ice influx from the valley walls, support rock glacier formation via talus accumulation. A quartz-dominated subsurface composition and discontinuous, well-developed desert pavements suggest initial rock glacier formation occurred before the late Quaternary. Major ion data from soil leaching analyses show higher salt concentrations in the rock glacier and talus samples that are close to hypersaline DJP. These observations suggest that DJP acts as a local salt source to the rock glacier, as well as the surrounding talus slopes that host water track systems that deliver solutes back into the lake, suggesting a local feedback system. Finally, the lack of lacustrine sedimentation on the rock glacier is inconsistent with the advance of a glacially dammed lake into South Fork during the Last Glacial Maximum.

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Knott, Jeffrey R., John C. Tinsley, and Stephen G. Wells. "Are the Benches at Mormon Point, Death Valley, California, USA, Scarps or Strandlines?" Quaternary Research 58, no. 3 (November 2002): 352–60. http://dx.doi.org/10.1006/qres.2002.2382.

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AbstractThe benches and risers at Mormon Point, Death Valley, USA, have long been interpreted as strandlines cut by still-stands of pluvial lakes correlative with oxygen isotope stage (OIS) 5e/6 (120,000–186,000 yr B.P.) and OIS-2 (10,000–35,000 yr B.P.). This study presents geologic mapping and geomorphic analyses (Gilbert's criteria, longitudinal profiles), which indicate that only the highest bench at Mormon Point (∼90 m above mean sea level (msl)) is a lake strandline. The other prominent benches on the north-descending slope immediately below this strandline are interpreted as fault scarps offsetting a lacustrine abrasion platform. The faults offsetting the abrasion platform most likely join downward into and slip sympathetically with the Mormon Point turtleback fault, implying late Quaternary slip on this low-angle normal fault. Our geomorphic reinterpretation implies that the OIS-5e/6 lake receded rapidly enough not to cut strandlines and was ∼90 m deep. Consistent with independent core studies of the salt pan, no evidence of OIS-2 lake strandlines was found at Mormon Point, which indicates that the maximum elevation of the OIS-2 lake surface was −30 m msl. Thus, as measured by pluvial lake depth, the OIS-2 effective precipitation was significantly less than during OIS-5e/6, a finding that is more consistent with other studies in the region. The changed geomorphic context indicates that previous surface exposure dates on fault scarps and benches at Mormon Point are uninterpretable with respect to lake history.

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Afzal, Shahzad, Mohammad Younas, and Karamat Ali. "Temporal Variability of the Water Quality of Saline Lakes from the Soan-Sakesar Valley, Salt Range, Pakistan." Water Quality Research Journal 33, no. 2 (May 1, 1998): 331–46. http://dx.doi.org/10.2166/wqrj.1998.018.

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Abstract Saline lakes from the Soan-Sakesar valley are a breeding and feeding habitat for many shorebirds and waterfowl. In 1994, water samples were collected from lakes Uchhali, Khabbaki and Jahlar and analyzed for a variety of parameters such as Secchi disk transparency, chlorophyll a, total phosphorus, nitrate, alkalinity, pH, total dissolved substances, calcium, magnesium, sodium, potassium, chloride and sulfate. Chemical changes observed in 1994 were compared to those of 1986. The three lakes studied can be characterized as hypereutrophic. Their chemistry is controlled mainly by an evaporation-crystallization process and dissolved salts supplied by underlying sedimentary submerged springs. Uchhali Lake is saline, while Khabbaki and Jahlar lakes are brackish. The chemistry of the lakes is discussed in relation to their acidification from coal mines.

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Zhong, S., X. Xu, X. Bian, and W. Lu. "Climatology of persistent deep stable layers in Utah's Salt Lake Valley, USA." Advances in Science and Research 6, no. 1 (March 21, 2011): 59–62. http://dx.doi.org/10.5194/asr-6-59-2011.

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Abstract. The characteristics of winter season persistent deep stable layers (PDSLs) over Utah's Salt Lake Valley are examined using 30-year twice daily rawinsonde soundings. The results highlight the basic climatological characteristics of the PDSLs, including the strengths of the inversion, the frequency of the occurrence, and the duration of the events. The data analyses also reveal linear trend, interannual variability, as well as the relationship between the interannual variability of PDSLs and the variability of large-scale circulations. Finally, the study investigates the large-scale atmosphere conditions accompanying the formation and destruction of the PDSL episodes.

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Benz, Harley M., and Robert B. Smith. "Elastic-wave propagation and site amplification in the Salt Lake valley, Utah, from simulated normal faulting earthquakes." Bulletin of the Seismological Society of America 78, no. 6 (December 1, 1988): 1851–74. http://dx.doi.org/10.1785/bssa0780061851.

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Abstract The two-dimensional seismic response of the Salt Lake valley to near- and far-field earthquakes has been investigated from simulations of vertically incident plane waves and from normal-faulting earthquakes generated on the basin-bounding Wasatch fault. The response to normal faulting earthquakes was simulated using a two-dimensional finite-element method and the plane-wave response was calculated from two-dimensional finite-difference simulations. The plane-wave simulations were then compared with observed site amplifications in the Salt Lake valley, based on seismic recordings from nuclear explosions in southern Nevada, that show 10 times greater amplification within the basin than measured values on hard-rock sites. While previous studies attribute this increased site amplification to the near-surface unconsolidated/consolidated alluvial fill contact, our synthetic seismograms suggest that in the frequency band 0.3 to 1.5 Hz at least one-half the site amplification can be attributed to the impedance contrast between the basin sediments and higher velocity basement rocks. Synthetic seismograms from vertically incident plane-wave sources and buried double-couple sources predict large amplitude Rayleigh-wave propagation from the edges of the basin and, in general, uniform site amplification. In contrast, near-field simulations of basin-bounding, normal-faulting earthquakes predict large-amplitude Rayleigh waves propagating westward from the fault across the basin. Spectra of synthetic accelerograms computed from the normal-faulting earthquakes shows that spectral amplification within the basin is primarily due to source directivity with a maxima near the surface projection of the fault that decays rapidly away from the fault. Importantly, the synthetic modeling of near-field earthquake sources show that near-field directivity effects are important and should be considered in an earthquake hazard assessment of the Salt Lake valley and similar geologic settings along the Wasatch Front.

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Ehleringer, James R., Stephannie Covarrubias Avalos, Brett J. Tipple, Luciano O. Valenzuela, and Thure E. Cerling. "Stable isotopes in hair reveal dietary protein sources with links to socioeconomic status and health." Proceedings of the National Academy of Sciences 117, no. 33 (August 3, 2020): 20044–51. http://dx.doi.org/10.1073/pnas.1914087117.

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Carbon and nitrogen isotope ratios in hair sampled from 65 communities across the central and intermountain regions of the United States and more intensively throughout 29 ZIP codes in the Salt Lake Valley, Utah, revealed a dietary divergence related to socioeconomic status as measured by cost of living, household income, and adjusted gross income. Corn-fed, animal-derived proteins were more common in the diets of lower socioeconomic status populations than were plant-derived proteins, with individual estimates of animal-derived protein diets as high as 75%; United States towns and cities averaged 57%. Similar patterns were seen across the socioeconomic status spectrum in the Salt Lake Valley. It is likely that corn-fed animal proteins were associated with concentrated animal-feeding operations, a common practice for industrial animal production in the United States today. Given recent studies highlighting the negative impacts of animal-derived proteins in our diets, hair carbon isotope ratios could provide an approach for scaling assessments of animal-sourced foods and health risks in communities across the United States.

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Chen, Ying, Francis L. Ludwig, and Robert L. Street. "Stably Stratified Flows near a Notched Transverse Ridge across the Salt Lake Valley." Journal of Applied Meteorology 43, no. 9 (September 2004): 1308–28. http://dx.doi.org/10.1175/1520-0450(2004)043<1308:ssfnan>2.0.co;2.

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Whiteman, C. David, Sebastian W. Hoch, John D. Horel, and Allison Charland. "Relationship between particulate air pollution and meteorological variables in Utah's Salt Lake Valley." Atmospheric Environment 94 (September 2014): 742–53. http://dx.doi.org/10.1016/j.atmosenv.2014.06.012.

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Olsen, Kim B., James C. Pechmann, and Gerard T. Schuster. "Simulation of 3D elastic wave propagation in the Salt Lake Basin." Bulletin of the Seismological Society of America 85, no. 6 (December 1, 1995): 1688–710. http://dx.doi.org/10.1785/bssa0850061688.

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Abstract We have used a 3D finite-difference method to model 0.2 to 1.2 Hz elastodynamic site amplification in the Salt Lake Valley, Utah. The valley is underlain by a sedimentary basin, which in our model has dimensions of 48 by 25 by 1.3 km. Simulations are carried out for a P wave propagating vertically from below and for P waves propagating horizontally to the north, south, east, and west in a two-layer model consisting of semi-consolidated sediments surrounded by bedrock. Results show that in general, sites with the largest particle velocities, cumulative kinetic energies, duration times of motion, and spectral magnitudes overlie the deepest parts of the basin. The maximum values of these parameters are generally found above steeply dipping parts of the basin walls. The largest vector particle velocities are associated with P or SV waves that come from within 10° of the source azimuth. Low-energy S and surface waves follow the strongest arrivals. The largest peak particle velocities, cumulative kinetic energies, signal durations, and spectral magnitudes in the simulations are, respectively, 2.9, 15.9, 40.0, and 3.5 times greater than the values at a rock site measured on the component parallel to the propagation direction of the incident P wave. Scattering and/or mode conversions at the basin boundaries contribute significantly to the signal duration times. As a check on the validity of our simulations, we compared our 3D synthetic seismograms for the vertically incident plane P wave to seismograms of nearly vertically incident teleseismic P waves recorded at an alluvium site in the valley and at a nearby rock site. The 3D synthetics for the alluvium site overestimate the relatively small amplification of the initial P wave and underestimate the large amplification of the coda. Using 2D simulations, we find that most of the discrepancies between the 3D synthetic and observed records can be explained by an apparently incorrect total sediment thickness, omission from the model of the near-surface low-velocity unconsolidated sediments and of attenuation, and the inexact modeling of the incidence angle of the teleseism. The records from a 2D simulation in which these deficiencies are remedied (with Q = 65), and which also includes topography and a near-surface velocity gradient in the bedrock, provide a better match to the teleseismic data than the records from the simple two-layer 3D simulation. Our results suggest that for steeply incident P waves, the impedance decrease and resonance effects associated with the deeper basin structure control the amplification of the initial P-wave arrival, whereas reverberations in the near-surface unconsolidated sediments generate the large-amplitude coda. These reverberations are caused mainly by P-to-S converted waves, and their strength is therefore highly sensitive to the incidence angle of the source.

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Whiteman, C. David, and Sebastian W. Hoch. "Pseudovertical Temperature Profiles in a Broad Valley from Lines of Temperature Sensors on Sidewalls." Journal of Applied Meteorology and Climatology 53, no. 11 (November 2014): 2430–37. http://dx.doi.org/10.1175/jamc-d-14-0177.1.

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AbstractPseudovertical temperature “soundings” from lines of inexpensive temperature sensors on the sidewalls of Utah’s Salt Lake valley are compared with contemporaneous radiosonde soundings from the north, open end of the valley. Morning [0415 mountain standard time (MST)] soundings are colder, and afternoon (1615 MST) soundings are warmer than radiosonde soundings because of warm and cold boundary layers that form over the slopes. Cross-valley temperature differences occur between east- and west-facing sidewalls because of differing insolation. Differences in vertically averaged pseudovertical and radiosonde temperatures are generally within 1°C, with a standard deviation of 2°–3°C. The pseudovertical soundings are especially good proxies for radiosondes in winter. The sounding comparisons identified along-valley differences in temperature, inversion depth, and lapse rate that have led to hypotheses concerning their causes, to be evaluated with future research. The low cost and much better time resolution of the pseudovertical soundings suggest that such lines will be a useful supplement to valley radiosondes and will have significant operational advantages if available in real time. Lines of surface-based sensors will prove useful in identifying intravalley meteorological differences and may be used to estimate free-air temperature structure in other valleys where radiosondes are unavailable.

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Young, Joseph Swyler, and C. David Whiteman. "Laser Ceilometer Investigation of Persistent Wintertime Cold-Air Pools in Utah’s Salt Lake Valley." Journal of Applied Meteorology and Climatology 54, no. 4 (April 2015): 752–65. http://dx.doi.org/10.1175/jamc-d-14-0115.1.

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AbstractAs part of the winter 2010/11 Persistent Cold-Air Pool Study in Utah’s Salt Lake Valley, a laser ceilometer was used to continuously measure aerosol-layer characteristics in support of an investigation of the meteorological processes producing the cold-air pools. A surface-based aerosol layer was present during much of the winter. Comparisons were made between ceilometer-measured and visual characteristics of the aerosol layers. A 3–4 January 2011 case study illustrated the meteorological value of time–height backscatter cross sections when used as a base map for meteorological analyses. A variety of meteorological mixing processes were illustrated using ceilometer backscatter data. The mean altitude of the top of the aerosol layer during undisturbed subperiods of the 1 December–7 February experimental period was 1811 m MSL, with a standard deviation of 185 m. The mean aerosol depth was ~500 m AGL in the 1200-m-deep valley. There was surprisingly little variation in the wintertime aerosol layer depth despite large variations in bulk atmospheric stability and ground-based fine particulate matter concentrations.

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Pankow, Kristine L., Jon Rusho, James C. Pechmann, J. Mark Hale, Katherine Whidden, Rebecca Sumsion, James Holt, Maria Mesimeri, Daniel Wells, and Keith D. Koper. "Responding to the 2020 Magna, Utah, Earthquake Sequence during the COVID-19 Pandemic Shutdown." Seismological Research Letters 92, no. 1 (November 4, 2020): 6–16. http://dx.doi.org/10.1785/0220200265.

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Abstract Two days after the University of Utah Seismograph Stations (UUSS) staff were required to leave campus and work remotely, an Mw 5.7 earthquake struck the Salt Lake Valley near the town of Magna, Utah. This event was the largest instrumentally recorded earthquake in the Salt Lake Valley and the largest earthquake ever felt by most residents. The timing of this event—at the start of a lockdown in response to the COVID-19 pandemic—made the UUSS response to this earthquake an extra challenge. Other factors such as a toxic plume caused by the ground shaking, inclement weather, and a mountain lion also impacted the work. The response tested the continuity of operations plan that had been in place since 2007, response protocols, and communications with partners and the public. Overall, the UUSS earthquake response was successful: A valuable and arguably unprecedented dataset of strong ground motions from normal faulting was generated, magnitudes and locations of thousands of earthquakes were shared in a timely fashion, unfounded rumors and general questions were promptly responded to via traditional and social media, and initial scientific results were submitted for publication.

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Berres, Thomas E. "CLIMATIC CHANGE AND LACUSTRINE RESOURCES AT THE PERIOD OF INITIAL AZTEC DEVELOPMENT." Ancient Mesoamerica 11, no. 1 (January 2000): 27–38. http://dx.doi.org/10.1017/s0956536100111101.

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Explanations for the emergence of the Aztec state need to consider changes in the climate and the potential effects resulting from these changes on the productivity of the lake network in the Valley of Mexico. Change in the human ecosystem is a complex process of interactions between multiple cultural variables and the environment. In this study, I examine the nature of three primary resources, fish, salt, and waterfowl, available for Early Aztec–period exploitation within the valley lake system. The intensification of lacustrine resource exploitation appears to be correlated with changing climatic conditions that occurred about a.d. 1150. Although the focus of this study is be on the cause-and-effect relationship between culture and environment, it is acknowledged that the environment is just one factor that must be considered to fully understand initial Aztec development.

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Winters, Y. D., T. K. Lowenstein, and M. N. Timofeeff. "Identification of Carotenoids in Ancient Salt from Death Valley, Saline Valley, and Searles Lake, California, Using Laser Raman Spectroscopy." Astrobiology 13, no. 11 (November 2013): 1065–80. http://dx.doi.org/10.1089/ast.2012.0952.

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Alexandrova, Olga A., Don L. Boyer, James R. Anderson, and Harindra J. S. Fernando. "The influence of thermally driven circulation on PM10 concentration in the Salt Lake Valley." Atmospheric Environment 37, no. 3 (January 2003): 421–37. http://dx.doi.org/10.1016/s1352-2310(02)00803-8.

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Chachere, Catherine N., and Zhaoxia Pu. "Connections Between Cold Air Pools and Mountain Valley Fog Events in Salt Lake City." Pure and Applied Geophysics 173, no. 9 (May 26, 2016): 3187–96. http://dx.doi.org/10.1007/s00024-016-1316-x.

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Smith, Rose M., Jeb C. Williamson, Diane E. Pataki, James Ehleringer, and Philip Dennison. "Soil carbon and nitrogen accumulation in residential lawns of the Salt Lake Valley, Utah." Oecologia 187, no. 4 (June 28, 2018): 1107–18. http://dx.doi.org/10.1007/s00442-018-4194-3.

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Wong, Ivan, Qimin Wu, and James C. Pechmann. "The 18 March 2020 M 5.7 Magna, Utah, Earthquake: Strong-Motion Data and Implications for Seismic Hazard in the Salt Lake Valley." Seismological Research Letters 92, no. 2A (January 20, 2021): 773–86. http://dx.doi.org/10.1785/0220200323.

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Abstract The 2020 oblique normal-faulting M 5.7 Magna mainshock has provided the best dataset of recorded strong ground motions for an earthquake within the Wasatch Front region, Utah, and the larger Basin and Range Province. We performed a preliminary evaluation of the strong motion and broadband data from this earthquake and compared the data with the Next Generation Attenuation - West2 Project (NGA-West2) ground-motion models (GMMs). The highest horizontal peak ground acceleration (PGA) recorded was 0.43g (geometric mean of the two horizontal components) at a station located above the rupture plane at a rupture distance of 8 km. Eleven stations recorded PGAs >0.20g. Most of these stations are located on the deep sedimentary deposits within the Salt Lake Valley, and all are at rupture distances <20 km. The data compare favorably with the NGA-West2 GMMs, although the expected variability was observed. PGAs exceed the GMM predictions at the closest distances for the source model that we used. The area of the strongest ground shaking encompassed the town of Magna, where some of the heaviest damage occurred. A significant implication of the 2020 Magna earthquake for seismic hazards in the Salt Lake Valley arises from the possibility that this earthquake occurred on the Salt Lake City segment of the Wasatch fault. If so, then the dip of this fault segment must decrease with depth to ≤30°–35°, as proposed by Pang et al. (2020)—at least along the northern part of the segment where the earthquake occurred. Because of the lack of information about the subsurface geometry of the Wasatch fault zone, modeling of this fault zone in seismic hazard analyses has assumed a moderate dip of 50°±15°. Assuming a more shallowly dipping fault results in higher estimates of ground shaking in future large earthquakes on this fault. Alternative interpretations of the Magna earthquake are that it occurred (1) on an auxiliary fault within the Wasatch fault zone or (2) on a listric section of the northern Salt Lake City segment that is not representative of the geometry of the whole fault segment.

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Lareau, Neil P., Erik Crosman, C. David Whiteman, John D. Horel, Sebastian W. Hoch, William O. J. Brown, and Thomas W. Horst. "The Persistent Cold-Air Pool Study." Bulletin of the American Meteorological Society 94, no. 1 (January 1, 2013): 51–63. http://dx.doi.org/10.1175/bams-d-11-00255.1.

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The Persistent Cold-Air Pool Study (PCAPS) was conducted in Utah's Salt Lake valley from 1 December 2010 to 7 February 2011. The field campaign's primary goal was to improve understanding of the physical processes governing the evolution of multiday cold-air pools (CAPs) that are common in mountain basins during the winter. Meteorological instrumentation deployed throughout the Salt Lake valley provided observations of the processes contributing to the formation, maintenance, and destruction of 10 persistent CAP episodes. The close proximity of PCAPS field sites to residences and the University of Utah campus allowed many undergraduate and graduate students to participate in the study. Ongoing research, supported by the National Science Foundation, is using the PCAPS dataset to examine CAP evolution. Preliminary analyses reveal that variations in CAP thermodynamic structure are attributable to a multitude of physical processes affecting local static stability: for example, synoptic-scale processes impact changes in temperatures and cloudiness aloft while variations in boundary layer forcing modulate the lower levels of CAPs. During episodes of strong winds, complex interactions between the synoptic and mesoscale f lows, local thermodynamic structure, and terrain lead to both partial and complete removal of CAPs. In addition, the strength and duration of CAP events affect the local concentrations of pollutants such as PM2.5.

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Nicoll, Kathleen, Andrew T. Yentsch, Kevin T. Jones, and Ronald J. Rood. "Site formation and Archaic geoarchaeology along the Jordan River, Great Salt Lake Valley, Utah USA." Quaternary International 342 (August 2014): 214–25. http://dx.doi.org/10.1016/j.quaint.2013.08.044.

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Kuprov, Roman, Delbert J. Eatough, Tyler Cruickshank, Neal Olson, Paul M. Cropper, and Jaron C. Hansen. "Composition and secondary formation of fine particulate matter in the Salt Lake Valley: Winter 2009." Journal of the Air & Waste Management Association 64, no. 8 (July 16, 2014): 957–69. http://dx.doi.org/10.1080/10962247.2014.903878.

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Vaughn, Kēhaulani, Jacob Fitisemanu, Inoke Hafoka, and Kehaulani Folau. "Unmasking the Essential Realities of COVID ‐19: The Pasifika Community in the Salt Lake Valley." Oceania 90, S1 (December 2020): 60–67. http://dx.doi.org/10.1002/ocea.5267.

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Mecate, Danielle, Rod Handy, Leon Pahler, Darrah Sleeth, Joemy Ramsay, and Camie Schaefer. "Temperature Inversion and Ultrafine Particulate/Near Ultrafine Particulate Matter Concentrations in the Salt Lake Valley." Technium: Romanian Journal of Applied Sciences and Technology 2, no. 7 (January 5, 2021): 422–35. http://dx.doi.org/10.47577/technium.v2i7.2263.

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Ultrafine particulate (UFP) matter exposures are associated with negative health outcomes. UFPs (<100nm) and near UFP (NUFP) matter (4.5nm - 250nm) are trapped by the bowl-like geography of the Salt Lake Valley causing winter inversions (i.e., trapped particulate matter (PM)). Enmont PUFP C100 and Grimm 1.109 particle counters were used to define NUFP concentrations during inversion (n=5) and non-inversion (n=5) days at 7 sites. NUFP concentrations served as a proxy for the UFP fraction. NUFP concentrations were log-transformed and multivariable mixed effects linear regression models determined if NUFP concentration differed between inversion and non-inversion or by length of inversion. Difference in fraction NUFP was also analyzed. The mean NUFP concentration was 1.49-fold higher during inversions (95% CI 1.11–2.02), whereas the fraction declined by 0.22 (95% CI -0.31– -0.13). Increased NUFP concentrations during inversions may lead to increased adverse health outcomes. These findings have serious implications for inversion-prone regions.

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Mecate, Danielle, Rod Handy, Leon Pahler, Darrah Sleeth, Joemy Ramsay, and Camie Schaefer. "Temperature Inversion and Ultrafine Particulate/Near Ultrafine Particulate Matter Concentrations in the Salt Lake Valley." Technium: Romanian Journal of Applied Sciences and Technology 2, no. 7 (January 5, 2021): 422–35. http://dx.doi.org/10.47577/technium.v2i7.2263.

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Ultrafine particulate (UFP) matter exposures are associated with negative health outcomes. UFPs (<100nm) and near UFP (NUFP) matter (4.5nm - 250nm) are trapped by the bowl-like geography of the Salt Lake Valley causing winter inversions (i.e., trapped particulate matter (PM)). Enmont PUFP C100 and Grimm 1.109 particle counters were used to define NUFP concentrations during inversion (n=5) and non-inversion (n=5) days at 7 sites. NUFP concentrations served as a proxy for the UFP fraction. NUFP concentrations were log-transformed and multivariable mixed effects linear regression models determined if NUFP concentration differed between inversion and non-inversion or by length of inversion. Difference in fraction NUFP was also analyzed. The mean NUFP concentration was 1.49-fold higher during inversions (95% CI 1.11–2.02), whereas the fraction declined by 0.22 (95% CI -0.31– -0.13). Increased NUFP concentrations during inversions may lead to increased adverse health outcomes. These findings have serious implications for inversion-prone regions.

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Pinto, J. O., D. B. Parsons, W. O. J. Brown, S. Cohn, N. Chamberlain, and B. Morley. "Coevolution of Down-Valley Flow and the Nocturnal Boundary Layer in Complex Terrain." Journal of Applied Meteorology and Climatology 45, no. 10 (October 1, 2006): 1429–49. http://dx.doi.org/10.1175/jam2412.1.

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Abstract An enhanced National Center for Atmospheric Research (NCAR) integrated sounding system (ISS) was deployed as part of the Vertical Transport and Mixing (VTMX) field experiment, which took place in October of 2000. The enhanced ISS was set up at the southern terminus of the Great Salt Lake Valley just north of a gap in the Traverse Range (TR), which separates the Great Salt Lake and Utah Lake basins. This location was chosen to sample the dynamic and thermodynamic properties of the flow as it passes over the TR separating the two basins. The enhanced ISS allowed for near-continuous sampling of the nocturnal boundary layer (NBL) and low-level winds associated with drainage flow through the gap in the TR. Diurnally varying winds were observed at the NCAR site on days characterized by weak synoptic forcing and limited cloud cover. A down-valley jet (DVJ) was observed on about 50% of the nights during VTMX, with the maximum winds usually occurring within 150 m of the surface. The DVJ was associated with abrupt warming at low levels as a result of downward mixing and vertical transport of warm air from the inversion layer above. Several processes were observed to contribute to vertical transport and mixing at the NCAR site. Pulses in the strength of the DVJ contributed to vertical transport by creating localized areas of low-level convergence. Gravity waves and Kelvin–Helmholtz waves, which facilitated vertical mixing near the surface and atop the DVJ, were observed with a sodar and an aerosol backscatter lidar that were deployed as part of the enhanced ISS. The nonlocal nature of the processes responsible for generating turbulence in strongly stratified surface layers in complex terrain confounds surface flux parameterizations typically used in mesoscale models that rely on Monin–Obukhov similarity theory. This finding has major implications for modeling NBL structure and drainage flows in regions of complex terrain.

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Whiteman, C. David, and Shiyuan Zhong. "Downslope Flows on a Low-Angle Slope and Their Interactions with Valley Inversions. Part I: Observations." Journal of Applied Meteorology and Climatology 47, no. 7 (July 1, 2008): 2023–38. http://dx.doi.org/10.1175/2007jamc1669.1.

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Abstract Thermally driven downslope flows were investigated on a low-angle (1.6°) slope on the west side of the floor of Utah’s Salt Lake Valley below the Oquirrh Mountains using data from a line of four tethered balloons running down the topographic gradient and separated by about 1 km. The study focused on the evolution of the temperature and wind structure within and above the slope flow layer and its variation with downslope distance. In a typical situation, on clear, undisturbed October nights a 25-m-deep temperature deficit of 7°C and a 100–150-m-deep downslope flow with a jet maximum speed of 5–6 m s−1 at 10–15 m AGL developed over the slope during the first 2 h following sunset. The jet maximum speed and the downslope volume flux increased with downslope distance. The downslope flows weakened in the late evening as the stronger down-valley flows expanded to take up more of the valley atmosphere and as ambient stability increased in the lower valley with the buildup of a nocturnal temperature inversion. Downslope flows over this low-angle slope were deeper and stronger than has been reported previously by other investigators, who generally investigated steeper slopes and, in many cases, slopes on the sidewalls of isolated mountains where the downslope flows are not subject to the influence of nighttime buildup of ambient stability within valleys.

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Lee#, Jasmine CH, Maurizio Zangari#, Brady L. Stein, Kimberly Hickman, Andrew Wilson, Alison Moliterno, Jerry L. Spivak, Victor R. Gordeuk, and Josef T. Prchal. "Could the Increased Prevalence of Thrombotic Complications at High Altitude In Polycythemia Vera (PV) Be Contributed by Hypoxia?" Blood 116, no. 21 (November 19, 2010): 1988. http://dx.doi.org/10.1182/blood.v116.21.1988.1988.

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Abstract Abstract 1988 # Both authors contributed equally. Thrombotic complications are a major cause of morbidity and mortality in polycythemia vera (PV). While the risk of PV thrombotic complications is significantly higher in patients with a previous history of thrombosis or transient ischemic attacks, advanced age (> 60 years), leukocytosis and possibly a high JAK2 V617F allelic burden, other contributing etiologies have not been excluded. It is unclear whether environmental variations including hypoxia could modify thrombosis risk. Chronic hypoxia induces many phenotypic changes, including increased erythropoietin production resulting in secondary erythrocytosis and pulmonary hypertension. Moreover, a congenital disorder of augmented hypoxia sensing at ambient oxygen tension, Chuvash polycythemia, is associated with a marked, yet unexplained, increased rate of thrombotic complications. Salt Lake City, UT is located in a valley at ~5,000 feet of altitude and the surrounding areas from which PV patients are referred ranges from 4,300 to 6,900 feet in altitude. In this area, the average hemoglobin concentration is 0.6–1.3 gm/dL higher than the average US value, indicating a physiological response to this level of hypoxia. To analyze the possible effect of moderate hypoxia on PV thrombotic complications, we retrospectively compared the history of thrombotic complications in PV patients from Salt Lake City and Baltimore, MD, a city with a referral area in which the elevation is <500 feet. A total of 237 PV patients were analyzed in this study; 166 were treated in Baltimore and 71 were treated in Salt Lake City, Their demographics are presented in the Table. Patients from Salt Lake City were older than the Baltimore patients, more often male, and had longer disease duration. A history of thrombosis was present in 58% of the Salt Lake City patients compared to 27% of the Baltimore patients (P <0.0001). After adjusting for age, sex and disease duration, Salt Lake City patients had an estimated 3.9-fold increase in the odds of history of thrombosis compared to Baltimore patients (95% confidence interval of 1.9 to 7.8; P = 0.0002). The analysis suggests that hypoxia may modify the PV phenotype. The degree of HIF-1 and HIF-2 augmentation and altered regulation of their target genes, and the potential for increased thrombotic risk due to environmental hypoxia should be evaluated prospectively in PV patients living at different altitudes. Disclosures: No relevant conflicts of interest to declare.

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Lu, Wei, and Shiyuan Zhong. "A numerical study of a persistent cold air pool episode in the Salt Lake Valley, Utah." Journal of Geophysical Research: Atmospheres 119, no. 4 (February 25, 2014): 1733–52. http://dx.doi.org/10.1002/2013jd020410.

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Cobley, L. A. E., and D. E. Pataki. "Vehicle emissions and fertilizer impact the leaf chemistry of urban trees in Salt Lake Valley, UT." Environmental Pollution 254 (November 2019): 112984. http://dx.doi.org/10.1016/j.envpol.2019.112984.

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Gómez-Navarro, Carolina, Diane E. Pataki, Eric R. Pardyjak, and David R. Bowling. "Effects of vegetation on the spatial and temporal variation of microclimate in the urbanized Salt Lake Valley." Agricultural and Forest Meteorology 296 (January 2021): 108211. http://dx.doi.org/10.1016/j.agrformet.2020.108211.

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48

Sun, Xia, and Heather A. Holmes. "Surface Turbulent Fluxes during Persistent Cold-Air Pool Events in the Salt Lake Valley, Utah. Part I: Observations." Journal of Applied Meteorology and Climatology 58, no. 12 (December 2019): 2553–68. http://dx.doi.org/10.1175/jamc-d-19-0053.1.

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AbstractThe land surface is coupled to the atmospheric boundary layer through surface turbulent fluxes. Persistent cold-air pools (PCAPs) form in topographic depressions where cold, dense air fills the valley basin and in the presence of air pollution is accompanied by poor air quality. For the first time, the surface turbulence dataset from seven monitors during the Persistent Cold-Air Pool Study conducted in Salt Lake Valley, Utah (December 2010–February 2011), are analyzed. We found that the surface sensible (H) and latent (LE) heat fluxes were lower during strong PCAP events compared with non-PCAPs. The higher ratio of heat flux to net radiation (H/Rn and LE/Rn) for strong PCAPs compared with weak PCAPs is suspected to be related to the presence of boundary layer clouds, which could enhance the turbulent mixing through cloud top–down mixing. The daily average ground heat flux (G) was a similar order of magnitude to H and LE during wintertime. The highest surface turbulent fluxes and energy balance closure occurred in the stability range of −0.05 < ξ ≤ −0.02, or under slightly unstable conditions, near the neutral stability range. The median surface exchange coefficient (Ch), a crucial parameter to determine surface turbulent fluxes in land surface models, was slightly higher at the bare land site (BL) than the short vegetation sites (PH and CR) in wintertime, suggesting the importance of dynamic land-use information in numerical models.

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Dorr, L. J., D. H. Nicolson, and L. K. Overstreet. "Bibliographic notes on H. Stansbury's Exploration and survey of …/ Expedition to the valley of the Great Salt Lake." Archives of Natural History 30, no. 2 (October 2003): 317–30. http://dx.doi.org/10.3366/anh.2003.30.2.317.

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Howard Stansbury's classic work is bibliographically complex, with two true editions as well as multiple issues of the first edition. The first edition was printed in Philadelphia; its 487 stereotyped pages were issued in 1852 under two different titles with three variant title-pages (an official US government issue and two trade issues). A second edition was printed in Washington in 1853 and had 495 typeset pages (with corrections and additions in the appendices). The issue of 1855 is identical to the 1852 trade issue, except for the change of the date on the title-page. Each issue and edition, with its bindings and plates, is described.

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Foster, Christopher S., Erik T. Crosman, and John D. Horel. "Simulations of a Cold-Air Pool in Utah’s Salt Lake Valley: Sensitivity to Land Use and Snow Cover." Boundary-Layer Meteorology 164, no. 1 (February 8, 2017): 63–87. http://dx.doi.org/10.1007/s10546-017-0240-7.

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Journal articles on the topic 'Salt Lake Valley'

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