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Utah State University

Publications

2018

Articles 1 - 6 of 6

Full-Text Articles in Physical Sciences and Mathematics

Mountain-Wave Propagation Under Transient Tropospheric Forcing: A Deepwave Case Study, Tanja C. Portele, Andreas Dörnbrack, Johannes S. Wagner, Sonja Gisinger, Benedikt Ehard, Pierre-Dominique Pautet, Markus Rapp Jun 2018

Mountain-Wave Propagation Under Transient Tropospheric Forcing: A Deepwave Case Study, Tanja C. Portele, Andreas Dörnbrack, Johannes S. Wagner, Sonja Gisinger, Benedikt Ehard, Pierre-Dominique Pautet, Markus Rapp

Publications

The impact of transient tropospheric forcing on the deep vertical mountain-wave propagation is investigated by a unique combination of in situ and remote sensing observations and numerical modeling. The temporal evolution of the upstream low-level wind follows approximately a cos2 shape and was controlled by a migrating trough and connected fronts. Our case study reveals the importance of the time-varying propagation conditions in the upper troposphere and lower stratosphere (UTLS). Upper-tropospheric stability, the wind profile, and the tropopause strength affected the observed and simulated wave response in the UTLS. Leg-integrated along-track momentum fluxes (-MFtrack) and amplitudes of …

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Seasonal Propagation Characteristics Of Mstids Observed At High Latitudes Over Central Alaska Using The Poker Flat Incoherent Scatter Radar, Michael R. Negale, Michael J. Taylor, M. J. Nicolls, Sharon L. Vadas, Kim Nielsen, Craig J. Heinselman May 2018

Seasonal Propagation Characteristics Of Mstids Observed At High Latitudes Over Central Alaska Using The Poker Flat Incoherent Scatter Radar, Michael R. Negale, Michael J. Taylor, M. J. Nicolls, Sharon L. Vadas, Kim Nielsen, Craig J. Heinselman

Publications

Near‐continuous electron density measurements obtained over a ∼3 year period, 2010–2013, using the Poker Flat Incoherent Scatter Radar (PFISR) in central Alaska (69°N, 147°W) have been analyzed to quantify the properties of over 650 high‐latitude medium‐scale traveling ionospheric disturbances (MSTIDs). Our analysis focused on the altitude range 100–300 km encompassing the lower ionosphere/thermosphere and yielded first full seasonal day/night distributions of MSTIDs at high northern latitudes with mean values: horizontal wavelength 446 km, horizontal phase speed 187 m/s, and period 41 min. These year‐round measurements fill an important summertime gap in existing MSTID measurements revealing predominantly eastward wave propagation during …

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Estimating Discharge In Low-Order Rivers With High-Resolution Aerial Imagery, Tyler V. King, Bethany T. Neilson, Mitchell T. Rasmussen Feb 2018

Estimating Discharge In Low-Order Rivers With High-Resolution Aerial Imagery, Tyler V. King, Bethany T. Neilson, Mitchell T. Rasmussen

Publications

Remote sensing of river discharge promises to augment in situ gauging stations, but the majority of research in this field focuses on large rivers (>50 m wide). We present a method for estimating volumetric river discharge in low-order (wide) rivers from remotely sensed data by coupling high-resolution imagery with one-dimensional hydraulic modeling at so-called virtual gauging stations. These locations were identified as locations where the river contracted under low flows, exposing a substantial portion of the river bed. Topography of the exposed river bed was photogrammetrically extracted from high-resolution aerial imagery while the geometry of the remaining inundated portion …

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Monthly Paleostreamflow Reconstruction From Annual Tree-Ring Chronologies, James H. Stagge, David E. Rosenberg, R. J. Derose, Tammy M. Rittenour Feb 2018

Monthly Paleostreamflow Reconstruction From Annual Tree-Ring Chronologies, James H. Stagge, David E. Rosenberg, R. J. Derose, Tammy M. Rittenour

Publications

Paleoclimate reconstructions are increasingly used to characterize annual climate variability prior to the instrumental record, to improve estimates of climate extremes, and to provide a baseline for climate-change projections. To date, paleoclimate records have seen limited engineering use to estimate hydrologic risks because water systems models and managers usually require streamflow input at the monthly scale. This study explores the hypothesis that monthly streamflows can be adequately modeled by statistically decomposing annual flow reconstructions. To test this hypothesis, a multiple linear regression model for monthly streamflow reconstruction is presented that expands the set of predictors to include annual streamflow reconstructions, …

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Unexpected Occurrence Of Mesospheric Frontal Gravity Wave Events Over South Pole (90°S), Pierre-Dominique Pautet, Michael J. Taylor, J. B. Snively, Christina Solorio Jan 2018

Unexpected Occurrence Of Mesospheric Frontal Gravity Wave Events Over South Pole (90°S), Pierre-Dominique Pautet, Michael J. Taylor, J. B. Snively, Christina Solorio

Publications

Since 2010, Utah State University has operated an infrared Advanced Mesospheric Temperature Mapper at the Amundsen–Scott South Pole station to investigate the upper atmosphere dynamics and temperature deep within the vortex. A surprising number of “frontal” gravity wave events (86) were recorded in the mesospheric OH(3,1) band intensity and rotational temperature images (typical altitude of ~87 km) during four austral winters (2012–2015). These events are gravity waves (GWs) characterized by a sharp leading wave front followed by a quasi-monochromatic wave train that grows with time. A particular subset of frontal gravity wave events has been identified in the past (Dewan …

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Investigating Gravity Waves In Polar Mesospheric Clouds Using Tomographic Reconstructions Of Aim Satellite Imagery, V. P. Hart, M. J. Taylor, T. E. Doyle, Yucheng Zhao, Pierre-Dominique Pautet, B. L. Carruth, D. W. Rusch, J. M. Russell Iii Jan 2018

Investigating Gravity Waves In Polar Mesospheric Clouds Using Tomographic Reconstructions Of Aim Satellite Imagery, V. P. Hart, M. J. Taylor, T. E. Doyle, Yucheng Zhao, Pierre-Dominique Pautet, B. L. Carruth, D. W. Rusch, J. M. Russell Iii

Publications

This research presents the first application of tomographic techniques for investigating gravity wave structures in polar mesospheric clouds (PMCs) imaged by the Cloud Imaging and Particle Size instrument on the NASA AIM satellite. Albedo data comprising consecutive PMC scenes were used to tomographically reconstruct a 3‐D layer using the Partially Constrained Algebraic Reconstruction Technique algorithm and a previously developed “fanning” technique. For this pilot study, a large region (760 × 148 km) of the PMC layer (altitude ~83 km) was sampled with a ~2 km horizontal resolution, and an intensity weighted centroid technique was developed to create novel 2‐D surface …

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