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Full-Text Articles in Physics
Extremely Sensitive Rayleigh-Scatter Lidar At Usu, Vincent B. Wickwar, Leda Sox, David Barton, Matthew T. Emerick
Extremely Sensitive Rayleigh-Scatter Lidar At Usu, Vincent B. Wickwar, Leda Sox, David Barton, Matthew T. Emerick
Posters
Rayleigh lidar opened a portion of the atmosphere, from 30 to 90 km, to ground-based observations. Rayleigh-scatter observations were made at the Atmospheric Lidar Observatory (ALO) at Utah State University (USU) from 1993–2004 between 45 and 90 km, creating a very dense data set consisting of ~5000 hours of observations carried out over ~900 nights. The lidar had a mirror of area 0.15 m2 and a frequency-doubled Nd:YAG laser operating at 532 nm at 30 Hz at ~21 W, giving a power-aperture product (PAP) of ~3.1 Wm2.
Interpretation (Or Is It Calibration?) Of Rayleigh-Scatter Lidar Signals, Vincent B. Wickwar, Leda Sox
Interpretation (Or Is It Calibration?) Of Rayleigh-Scatter Lidar Signals, Vincent B. Wickwar, Leda Sox
Presentations
No abstract provided.
Rayleigh Lidar Observations Of The Mid-Latitude Mesosphere During Stratospheric Warming Events And A New Rayleigh-Mie-Raman Lidar At Usu, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron, Matthew T. Emerick
Rayleigh Lidar Observations Of The Mid-Latitude Mesosphere During Stratospheric Warming Events And A New Rayleigh-Mie-Raman Lidar At Usu, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron, Matthew T. Emerick
Presentations
No abstract provided.
Multi-Year Observations Of Mid-Latitude Middle Atmospheric Winds, Waves, And Temperature Associated With Ssw Events Over Northern Utah, Chad Fish, Vincent B. Wickwar, B. Thurairajah, Jan J. Sojka, F. T. Berkey, S. Bailey, Titus Yuan, Michael J. Taylor, N. Mitchell, W. Hocking
Multi-Year Observations Of Mid-Latitude Middle Atmospheric Winds, Waves, And Temperature Associated With Ssw Events Over Northern Utah, Chad Fish, Vincent B. Wickwar, B. Thurairajah, Jan J. Sojka, F. T. Berkey, S. Bailey, Titus Yuan, Michael J. Taylor, N. Mitchell, W. Hocking
Presentations
We investigate the behavior of 14 years of wind, wave, and temperature observations in the middle atmosphere over northeastern Utah, USA during periods of sudden stratospheric warming events. This systematic review of the impacts of sudden stratospheric warming events on the middle atmosphere at a northern mid-latitude site is conducted using ground based measurements from imaging Doppler interferometry and meteor wind radar and Na and Raleigh lidar and space based measurements made by the Sounding of the Atmosphere Using Broadband Emission Radiometry sensor onboard the NASA sponsored Thermosphere Ionosphere mesosphere Energetics Dynamics Mission.
Rayleigh Lidar Temperature Studies In The Upper Mesosphere And Lower Thermosphere, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Matthew T. Emerick
Rayleigh Lidar Temperature Studies In The Upper Mesosphere And Lower Thermosphere, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Matthew T. Emerick
Posters
Rayleigh lidar technology opened the middle atmosphere (from 30–90 km) to ground-based observations. The upgraded system at the Atmospheric Lidar Observatory (ALO) on the campus of Utah State University (41.74, 111.81) has shown that these ground-based observations can be extended to 109 km, with the goal of reaching 120 km. The resultant study of short and long-term temperature trends, using Rayleigh lidar, contributes immensely to the overall understanding of the properties and dominant physical processes in the middle atmosphere and Mesosphere-Lower Thermosphere (MLT) region. Temperature variations on short time scales, from minutes to days, give insight into the effects of …
First Temperature Observations With The Usu Very Large Rayleigh Lidar: An Examination Of Mesopause Temperatures, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham, Lance W. Petersen, Matthew T. Emerick
First Temperature Observations With The Usu Very Large Rayleigh Lidar: An Examination Of Mesopause Temperatures, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham, Lance W. Petersen, Matthew T. Emerick
Posters
As the impetus for extended observational measurements throughout the middle atmosphere has increased1 , the limits of previous instrumentation need to be pushed. The Rayleigh lidar group at the Atmospheric Lidar Observatory (ALO) at Utah State University has pushed such limits on existing Rayleigh scatter lidar technology and, through major upgrades to the previous lidar system, has been able to gather temperature measurements in the upper mesosphere and lower thermosphere from approximately 70P109 km. A data campaign with the new system was conducted around the annual temperature minimum, centered on late June 2012, in this region. The temperatures from this …
Upgraded Alo Rayleigh Lidar System And Its Improved Gravity Wave Measurements, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham
Upgraded Alo Rayleigh Lidar System And Its Improved Gravity Wave Measurements, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham
Graduate Student Posters
The Rayleigh-Scatter lidar system at the Atmospheric Lidar Observatory (ALO) on the Utah State campus is currently going through a series of upgrades to significantly improve its observational abilities. A specific objective of these upgrades is to expand the altitude range over which backscattered photons can be collected. A second objective is to increase the sensitivity of the instrument to be able to analyze the raw data at finer temporal and/or spatial resolutions. By measuring relative densities, the system will be able to produce absolute temperatures and relative density perturbations, which illustrate gravity wave structures. Gravity wave studies will significantly …
Rayleigh-Lidar Observations Of Mesospheric Instabilities, Gabriel C. Taylor, Durga N. Kafle, Vincent B. Wickwar
Rayleigh-Lidar Observations Of Mesospheric Instabilities, Gabriel C. Taylor, Durga N. Kafle, Vincent B. Wickwar
Posters
From 1993 to 2004 the Utah State University Rayleigh lidar, known as the USU green laser, collected 900 nights of data from the mesosphere (45-90 km). From these observations profiles of relative neutral densities and absolute temperatures were derived. Usually, the atmosphere is horizontally stratified with a balance between gravitational and pressure forces. When this balance is perturbed, it leads to the generation of buoyancy or “gravity” waves. An example of these is clear air turbulence, which can have dramatic effects on airplanes. As these waves propagate upward, the decrease in atmospheric density and conservation of energy combine to give …
Observations Of A Noctilucent Cloud Above Logan, Utah (41.7°N, 111.8°W) In 1995, Joshua P. Herron, Vincent B. Wickwar, P J. Espy, J W. Merriwether
Observations Of A Noctilucent Cloud Above Logan, Utah (41.7°N, 111.8°W) In 1995, Joshua P. Herron, Vincent B. Wickwar, P J. Espy, J W. Merriwether
All Physics Faculty Publications
A Rayleigh-scatter lidar has been operated at the Atmospheric Lidar Observatory (ALO) on the Utah State University (USU) campus (41.7°N, 111.8°W) since August 1993. During the morning of 22 June 1995, lidar returns from a noctilucent cloud (NLC) were observed for approximately 1 hr, well away from the twilight periods when NLCs are visible. This detection of an NLC at this latitude shows that the first reported sighting, in 1999 (Wickwar et al., 2002), was not a unique occurrence. This 1995 observation differs from the 1999 one in that temperatures could be deduced. Near the 83-km NLC altitude the temperatures …
Rayleigh-Lidar Observations Of Mesospheric Mid-Latitude Density Climatology Above Utah State University, Eric M. Lundell, Vincent B. Wickwar
Rayleigh-Lidar Observations Of Mesospheric Mid-Latitude Density Climatology Above Utah State University, Eric M. Lundell, Vincent B. Wickwar
Posters
Data from Rayleigh lidars have been used extensively to derive temperatures in the mesospheric region of the atmosphere. However, these data have not been used extensively in a similar way to derive neutral densities. We report on one such mid-latitude, density climatology between 45 and ~90 km, based on nearly 600 good nights of observations carried out since 1993 at the Atmospheric Lidar Observatory (ALO) at Utah State University (41.7°N 111.8°W). They produce relative density profiles that are then normalized at 45 km to an empirical model, in this case the MSISe00 model. Despite this normalization, significant differences are found …