Physics Commons^™

Mid-Latiude Rayleigh-Mie-Raman Lidar For Observations From 15 To 120 Km, Vincent B. Wickwar, Leda Sox, Joshua P. Herron, 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. The lidar consisted of a 0.44-m diameter mirror, a frequency-doubled Nd:YAG laser opera'ng at 532-nm at 30- Hz at either 18- or 24-W, giving power- aperture products (PAPs) of 2.7- or 3.6- Wm2, respec'vely, and one detector channel. An example of what was accomplished with this system is shown as part of Fig. 1. The temperature climatology was based on ~5000 hours …

Temperatures In The Mid-Latitude Mesosphere During Sudden Stratospheric Warmings As Determined From Rayleigh Lidar Data, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron

Graduate Student Posters

Sudden Stratospheric Warmings (SSWs) are major disturbances in the polar region of the winter hemisphere that cause major changes in stratospheric temperature and circulation. SSWs are characterized by a temperature increase of tens of degrees Kelvin, averaged over 60°-90° latitude, and a weakening of the polar vortex that persists for the order of a week at the 10 hPa level (roughly 32 km) [Labitzke and Naujokat, 2000]. The polar vortices are cyclones centered on both of the Earth’s poles that are present from the mid-troposphere to the lower stratosphere. Eastward zonal winds define the strong polar vortices in the winter. …

Statistical Characteristics Of Polar Mesospheric Gravity Waves Observed Over Alaska, Michael Negale, Kim Nielsen, Michael J. Taylor, Dominique Pautet, Margit Dyrland

Physics Student Research

Momentum deposition by short-period (<1 hr) gravity waves is known to play a major role in the global circulation in the mesosphere and lower thermosphere (MLT) region ~80-100 km (e.g. Fritts and Alexander, 2003). Observations of these waves over the Arctic Region are few and their impact on the Arctic MLT region is of high interest, but has yet to be determined. The Mesospheric Airglow Imaging and Dynamics (MAID) project was initiated in January 2011 to investigate short-period gravity wave dynamics over central Alaska. MAID is a collaborative project between Utah Valley University (UVU) (Principle Investigator Kim Nielsen), Utah State University (USU), and the University of Alaska, Fairbanks (UAF).

The main goals of this project are to:
-Establish a long-term climatology of short-period gravity waves observed in the Arctic MLT region.
-Determine dominant source regions and potential sources of the observed waves.
-Investigate the impact of large-scale waves (tides and planetary waves) on the short-period wave field.
-Perform quantitative comparison between Arctic and Antarctic winter-time dynamics.

In this poster, we focus on quantifying the climatology of short-period gravity waves during two winter seasons (2011-2012) over central Alaska.

Satellite And Ground-Based Measurements Of Mesospheric Temperature Variability Over Cerro Pachon, Chile (30.3° S), Jonathan Pugmire, Michael J. Taylor, Yucheng Zhao, P. D. Pautet, J. M. Russell

Graduate Student Posters

— Observations of mesospheric OH (6,2) rotational temperatures by the Utah State University Mesospheric Temperature Mapper (MTM) located at the Andes Lidar Observatory, Cerro Pachon, Chile (30.3◦ S, 70.7◦ W) reveal a large range of nightly variations induced by atmospheric gravity waves and tides, as well as strong seasonal oscillations. This study investigates MTM temperature variability over the past 4 years comprising over 800 nights of high-quality data and compares the results with MTM measurements from Maui, Hawaii (2001-2005) and coincident mesospheric temperature measurement by the SABER instrument on the NASA TIMED satellite.

Winter Climatology Of Short-Period Polar Mesospheric Gravity Waves Observed Over Poker Flat Research Range, Alaska (65 O N, 147 O W), Michael Negale, Kim Nielsen, Michael J. Taylor, Dominique Pautet

Physics Student Research

Short-period gravity wave observations over the Arctic region are few and their impact on the Arctic mesosphere lower thermosphere region via momentum deposition is of high interest. The Mesospheric Airglow Imaging and Dynamics project was initiated in January 2011 to investigate the presence and dynamics of these waves over the interior of Alaska. Observations were made from Poker Flat Research Range (PFRR) using an all-sky imager. This site provides an exceptional opportunity to establish a long-term climatology of short-period gravity waves in the Arctic Region. We present summary measurements of prominent gravity waves over two consecutive winters and compare their …

Ground-Based Observations With A Rayleigh-Mie-Raman Lidar From 15-120 Km, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, David L. Barton, Matthew T. Emerick

Graduate Student Posters

Rayleigh lidar systems have historically made ground-based observations of the upper atmosphere (stratosphere and mesosphere) from 35-90 km. This technology has helped fill the data collection gap between the troposphere and space. Recently our Rayleigh lidar group at the Atmospheric Lidar Observatory on the campus of Utah State University (42° N, 112° W) upgraded the original lidar system in order to extend the measurement range for neutral densities and temperatures to higher altitudes and has increased the upper limit, so far, from 90 to 110 km. Next, we will extend the lower altitude limit downward to 15 km. This will …

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.

Midlatitude, Rayleigh-Mie-Raman Lidar For Observations From 15 To 120 Km, Vincent B. Wickwar, Leda Sox, Joshua P. Herron, Matthew T. Emerick

Presentations

No abstract provided.

The Mid-Latitude Mesosphere’S Response To Sudden Stratospheric Warmings As Determined From Rayleigh Lidar Temperatures, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron

Presentations

The original Rayleigh-scatter lidar that operated at the Atmospheric Lidar Observatory (ALO; 41.7°N, 111.8°W) in the Center for Atmospheric and Space Sciences (CASS) on the campus of Utah State University (USU), collected temperature data for 11 years, from 1993 through 2004. The temperatures derived from these data extended over the mesosphere, from 45 to 90 km. Recently, they were combined with other observations to examine the mid-latitude responses to Sudden Stratospheric Warmings (SSWs) in the polar regions. (The other observational instruments being an ionosonde, a meteor wind radar, a Na lidar, and a satellite.) Extensive Rayleigh lidar observations were made …

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.

Modeling The Ionospheric E And F1 Regions: Using Sdo-Eve Observations As The Solar Irradiance Driver, Jan Josef Sojka, Joseph B. Jensen, Michael David, Robert W. Schunk, Tom Woods, Frank Eparvier

All Physics Faculty Publications

Over the altitude range of 90–150 km, in dayside nonauroral regions, ionization is controlled almost entirely by solar ultraviolet irradiance; the response time for ionization during solar exposure is almost instantaneous, and likewise, the time scale for recombination into neutral species is very fast when the photoionizing source is removed. Therefore, if high-resolution solar spectral data are available, along with accurate ionization cross sections as a function of wavelength, it should be possible to model this ionospheric region with greater accuracy. The Extreme Ultraviolet Variability Experiment (EVE) instrument on the National Aeronautics and Space Administration Solar Dynamics Observatory (SDO) satellite, …

The Upgraded Rayleigh Lidar At Usu’S Atmospheric Lidar Observatory, Vincent B. Wickwar, Leda Sox, Joshua P. Herron

All Physics Faculty Presentations

No abstract provided.

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 …

Observations Of Mesospheric Temperature Variability Over The Andes, Jonathan Pugmire, Michael J. Taylor, Yucheng Zhao, P. D. Paudet, James M. Russell

Graduate Student Posters

Observations of mesospheric OH(6,2) rotational temperatures by the Utah State University Mesospheric Temperature Mapper (MTM) located at the Andes Lidar Observatory, Cerro Pachon, Chile (30.3°S, 70.7°S) reveal a large range of nightly variations induced by atmospheric gravity waves and tides, as well as strong seasonal oscillations. This study investigates MTM temperature variability over the past 3.5 years comprising over 800 nights of high-quality data and compares the results with ground-based spectrometric measurements from nearby El Leoncito Observatory, Argentina, Maui-MALT, Hawaii MTM measurements (2001-2005) and coincident mesospheric temperature measurement by SABER on the NASA TIMED satellite.

Winter Climatology Of Short-Period Mesospheric Gravity Waves Over Alaska, Michael Negale, Kim Nielsen, Michael J. Taylor, Dominique Pautet

Physics Student Research

Momentum deposition by short-period (<1 h) gravity waves is known to play a major role in the global circulation in the mesosphere and lower thermosphere (MLT) region ~80-100 km (e.g. Fritts and Alexander, 2003). Observations of these waves over the Arctic region are few and their impact on the Arctic MLT region is of high interest, but has yet to be determined. The Mesospheric Airglow Imaging and Dynamics (MAID) project was initiated in January 2011 to investigate short-period gravity wave dynamics over central Alaska.

In this poster, we focus on quantifying the climatology of short-period gravity waves during two winter seasons (2011-2012) over central Alaska

Middle Atmosphere Temperature Results From A New, High-Powered, Large-Aperture Rayleigh Lidar, Leda Sox, Vincent B. Wickwar, Joshua P. Herron

Conference publications

In June–July 2012, observations were carried out using the recently upgraded, large-aperture, Rayleigh-scatter lidar system located at the Atmospheric Lidar Observatory (ALO) on the campus of Utah State University, in Logan, UT (41.7 N, 111.8 W). This time period was significant because it enabled us to observe the annual temperature minimum in the upper mesosphere-lower thermosphere region. The data collected during the campaign were analyzed for temperatures between ~70–109 km. The results above ~95 km are the first obtained with a Rayleigh-scatter lidar, extending the technique well into the lower thermosphere. A great deal of variability from night-to-night is evident …

Lunar Tidal Effects In The Electrodynamics Of The Low-Latitude Ionosphere, Brian David Tracy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In order to model and perform better forecasts of the upper atmosphere, we have studied variations in the equatorial ionosphere due to lunar tidal forcing. We used extensive measurements made by the Jicamarca Unattended Long-Term Investigations of the Ionosphere and Atmosphere (JULIA) and Incoherent Scatter Radar (ISR) systems at Jicamarca, Peru during geomagnetic quiet conditions to determine the season, local time, and lunar age-dependent lunar tidal effects on equatorial vertical plasma drifts. The amplitudes and phases of the semimonthly and monthly lunar tidal perturbations were derived using a least squares method. Our results indicate that, as expected, lunar tidal effects …

Resolving Ionospheric E-Region Modeling Challenges: The Solar Photon Flux Dependence, Joseph B. Jensen, Jan J. Sojka, Michael David, Kent Tobiska, Robert W. Schunk, Tom Woods, Frank Eparvier

Browse All Undergraduate research

The EVE instrument of the NASA Solar Dynamics Observatory (SDO) provides for the first time EUV and XUV measurements of the solar irradiance that adequately define the major source of ionization of the atmosphere. In our study we modeled the E-region of the ionosphere and analyzed how it is affected by the solar irradiance data obtained by EVE and contrast this with the S2000 Solar Irradiance model, used previously. The ionosphere has two major layers, the E-layer at 100 km, and the F-layer at 300 km. The difference in solar irradiances are small except at some wavelength bands, it is …

Resolving Ionospheric E-Region Modeling Challenges: The Solar Photon Flux Dependence, Joseph B. Jensen, Jan J. Sojka, Michael David, Kent Tobiska, Robert W. Schunk, Tom Woods, Frank Eparvier

Student Showcase

No abstract provided.

Ionospheric Induced Scintillation: A Space Weather Enigma, Jan Josef Sojka

All Physics Faculty Publications

The effect of scintillation on radio signals whose propagation path involves the Earth’s ionosphere is analogous to the allies of World War II receiving radio messages that had passed through the Enigma machine. In both these cases, man-made information has been encrypted and transmitted via radio. The two encryption methods are shown in Figure 1. The right panel shows a World War II Enigma machine used extensively by German U-boats to convey encrypted messages transmitted by radio [Perera, 2010]. The left panel gives an extreme example of a mapping of ionospheric irregularities at 3 m, which creates very severe scintillation …

Coordinated Investigation Of Summer Time Mid-Latitude Descending E Layer (Es) Perturbations Using Na Lidar, Ionosonde, And Meteor Wind Radar Observations Over Logan, Utah (41.7°N, 111.8°W), Tao Yuan, Chad Fish, Jan Josef Sojka, D. Rice

All Physics Faculty Publications

It is well known that there is a strong correlation between the formation of a descending sporadic E layer (E_s) and the occurrence of large upper atmospheric zonal wind shears, most likely driven by solar thermal tides and/or gravity waves. We present new results of E_sperturbation events captured between 13 and 17 July 2011 (UT days 194–198) as part of a coordinated campaign using a wind/temperature Na lidar at Utah State University [41.7ºN, 111.8°W], and a Canadian Advanced Digital Ionosonde (CADI; Scientific Instrumentation Ltd., Saskatoon, Saskatchewan, Canada) and SkiYMet meteor wind radar, both located at nearby …

High-Latitude Short-Period Mesospheric Gravity Wave Dynamics And Winter Climatology, Michael Negale, Kim Nielsen, Michael J. Taylor, Dominique Pautet, Margit Dyrland

Physics Student Research

Short-period gravity wave observations over the Arctic region are few and their impact on the Arctic mesosphere lower thermosphere region via momentum deposition is of high interest. The Mesospheric Airglow Imaging and Dynamics project was initiated in January 2011 to investigate the presence and dynamics of these waves over the interior of Alaska. Observations were made from Poker Flat Research Range (PFRR) using an all-sky imager. This site provides an exceptional opportunity to establish a long-term climatology of short-period gravity waves in the Arctic Region. We present summary measurements of prominent gravity waves over two consecutive winters and compare their …