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Full-Text Articles in Physics

Absolute Neutral Densities And Temperatures And Their Climatologies In The Middle Atmosphere Using An Optimal Estimation Method With Rayleigh-Scatter Lidar Observations Obtained At Utah State University, Jonathan L. Price Dec 2021

Absolute Neutral Densities And Temperatures And Their Climatologies In The Middle Atmosphere Using An Optimal Estimation Method With Rayleigh-Scatter Lidar Observations Obtained At Utah State University, Jonathan L. Price

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Earth’s atmosphere is comprised of layers which can be defined by their temperature characteristics. These layers are the troposphere, stratosphere, mesosphere and thermosphere. The region where life exists is in the troposphere, however the study of the layers above is important as changes in these regions can directly impact, or indicate significant changes in, weather in the troposphere. The mesosphere is the least well-known region because it is the most difficult to observe. One of the best tools for observing this region is the Rayleigh-scatter lidar. It is capable of remotely observing the entirety of the mesosphere with good …


Comparisons Of Mesospheric Temperatures Between 70 And 110 Km: Usu Lidar, Nasa's Timed Satellite, And The Msis2 Empirical Model, David M. Collins May 2021

Comparisons Of Mesospheric Temperatures Between 70 And 110 Km: Usu Lidar, Nasa's Timed Satellite, And The Msis2 Empirical Model, David M. Collins

Physics Capstone Projects

Earth’s atmosphere can be characterized by its temperature structure, dividing the atmosphere into natural discrete regions. The mesosphere (50 to ~100 km) has been the least studied. Rayleigh-scatter lidars (RSL) and rockets can obtain local, high-resolution measurements above one spot, while satellites looking almost horizontally obtain global measurements. These two methods of measuring atmospheric conditions are compared using the USU RSL and the SABER instrument on NASA’s TIMED satellite. These measurements were graphed to show four sets of temperatures from several sources in the atmospheric region 70 km to 110 km above USU. The results show similar temperatures for many …


Evidence For Horizontal Blocking And Reflection Of A Small‐Scale Gravity Wave In The Mesosphere, Neal R. Criddle, Pierre-Dominique Pautet, Tao Yuan, C. Heale, J. Snively, Yucheng Zhao, Michael J. Taylor Apr 2020

Evidence For Horizontal Blocking And Reflection Of A Small‐Scale Gravity Wave In The Mesosphere, Neal R. Criddle, Pierre-Dominique Pautet, Tao Yuan, C. Heale, J. Snively, Yucheng Zhao, Michael J. Taylor

All Physics Faculty Publications

The variations of the horizontal phase velocity of an internal gravity wave, generated by wave “blocking” or “reflection” due to an inhomogeneous wind field, have been predicted theoretically and numerically investigated but had yet to be captured experimentally. In this paper, through a collaborative observation campaign using a sodium (Na) Temperature/Wind lidar and a collocated Advanced Mesospheric Temperature Mapper (AMTM) at Utah State University (USU), we report the first potential evidence of such a unique gravity wave process. The study shows that a small‐scale wave, captured by the AMTM, with initial observed horizontal phase velocity of 37 ± 5 m/s …


The Long‐Term Trends Of Nocturnal Mesopause Temperature And Altitude Revealed By Na Lidar Observations Between 1990 And 2018 At Midlatitude, Tao Yuan, Stanley C. Solomon, Chiao -Y. She, D. A. Krueger, Han-Li Liu May 2019

The Long‐Term Trends Of Nocturnal Mesopause Temperature And Altitude Revealed By Na Lidar Observations Between 1990 And 2018 At Midlatitude, Tao Yuan, Stanley C. Solomon, Chiao -Y. She, D. A. Krueger, Han-Li Liu

All Physics Faculty Publications

The mesopause, a boundary between mesosphere and thermosphere with the coldest atmospheric temperature, is formed mainly by the combining effects of radiative cooling of CO2, and the vertical adiabatic flow in the upper atmosphere. A continuous multidecade (1990‐2018) nocturnal temperature data base of an advanced Na lidar, obtained at Fort Collins, CO (41°N, 105°W), and at Logan, UT (42°N, 112°W), provides an unprecedented opportunity to study the long‐term variations of this important atmospheric boundary. In this study, we categorize the lidar‐observed mesopause into two categories: the “high mesopause” (HM) above 97 km during nonsummer months, mainly formed through the radiative …


Photochemistry On The Bottom Side Of The Mesospheric Na Layer, Tao Yuan, Wuhu Feng, John M. C. Plane, Daniel R. Marsh Mar 2019

Photochemistry On The Bottom Side Of The Mesospheric Na Layer, Tao Yuan, Wuhu Feng, John M. C. Plane, Daniel R. Marsh

All Physics Faculty Publications

Lidar observations of the mesospheric Na layer have revealed considerable diurnal variations, particularly on the bottom side of the layer, where more than an order-of-magnitude increase in Na density has been observed below 80 km after sunrise. In this paper, multi-year Na lidar observations are utilized over a full diurnal cycle at Utah State University (USU) (41.8o N, 111.8o W) and a global atmospheric model of Na with 0.5 km vertical resolution in the mesosphere and lower thermosphere (WACCM-Na) to explore the dramatic changes of Na density on the bottom side of the layer. Photolysis of the principal reservoir NaHCO3 …


Mesospheric Gravity Wave Climatology And Variances Over The Andes Mountains, Jonathan Rich Pugmire Dec 2018

Mesospheric Gravity Wave Climatology And Variances Over The Andes Mountains, Jonathan Rich Pugmire

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Look up! Travelling over your head in the air are waves. They are present all the time in the atmosphere all over the Earth. Now imagine throwing a small rock in a pond and watching the ripples spread out around it. The same thing happens in the atmosphere except the rock is a thunderstorm, the wind blowing over a mountain, or another disturbance. As the wave (known as a gravity wave) travels upwards the thinning air allows the wave to grow larger and larger. Eventually the gravity wave gets too large – and like waves on the beach – it …


Simultaneous Rayleigh-Scatter And Sodium Resonance Lidar Temperature Comparisons In The Mesosphere-Lower Thermosphere, Leda Sox, Vincent B. Wickwar, Tao Yuan, Neal R. Criddle Aug 2018

Simultaneous Rayleigh-Scatter And Sodium Resonance Lidar Temperature Comparisons In The Mesosphere-Lower Thermosphere, Leda Sox, Vincent B. Wickwar, Tao Yuan, Neal R. Criddle

All Physics Faculty Publications

The Utah State University (USU) campus (41.7°N, 111.8°W) hosts a unique upper atmospheric observatory that houses both a high-power, large-aperture Rayleigh lidar and a Na lidar. For the first time, we will present 19 nights of coordinated temperature measurements from the two lidars, overlapping in the 80–110 km observational range, over one annual cycle (summer 2014 to summer 2015). This overlap has been achieved through upgrades to the existing USU Rayleigh lidar that increased its observational altitude from 45–95 to 70–115 km and by relocating the Colorado State Na lidar to the USU campus. Previous climatological comparisons between Rayleigh and …


Design And Characterization Of A Time-Of-Flight Mass Spectrometer For Composition Measurements In The Upper Atmosphere, E. Addison Everett May 2017

Design And Characterization Of A Time-Of-Flight Mass Spectrometer For Composition Measurements In The Upper Atmosphere, E. Addison Everett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The mesosphere/lower thermosphere (MLT) is perhaps the least understood region of Earth's atmosphere. Too high for balloons and winged aircraft, yet too low for satellites, direct access to the MLT to make in-situ measurements is via high-speed sounding rockets for brief periods of at most a few minutes. Mass spectrometers have previously been used to make composition measurements in this region. But, mass spectrometry in the MLT is difficult, mainly due to the ambient pressures here and also the high speeds and short flight durations of sounding rocket missions. Time-of-flight mass spectrometers (TOF-MS) are capable of making fast, accurate measurements …


Effects Of Major Sudden Stratospheric Warmings Identified In Midlatitude Mesospheric Rayleigh-Scatter Lidar Temperatures, Leda Sox, Vincent B. Wickwar, Chad Fish, Josh Herron Dec 2014

Effects Of Major Sudden Stratospheric Warmings Identified In Midlatitude Mesospheric Rayleigh-Scatter Lidar Temperatures, Leda Sox, Vincent B. Wickwar, Chad Fish, Josh Herron

Physics Student Research

Mesospheric temperature anomalies associated with Sudden Stratospheric Warmings (SSWs) have been observed extensively in the polar regions. However, observations of these anomalies at midlatitudes are sparse. The very dense 11-year data set, collected between 1993–2004, with the Rayleigh-scatter lidar at the Atmospheric Lidar Observatory (ALO; 41.7°N, 111.8°W) at the Center for Atmospheric and Space Sciences (CASS) on the campus of Utah State University (USU), has been carefully examined for such anomalies. The temperatures derived from these data extend over the mesosphere, from 45 to 90 km. During this period extensive data were acquired during seven major SSW events. In this …


The First Ten Months Of Investigation Of Gravity Waves And Temperature Variability Over The Andes, Jonathan Pugmire, Neal Criddle, Michael J. Taylor, P. D. Pautet, Yucheng Zhao Oct 2014

The First Ten Months Of Investigation Of Gravity Waves And Temperature Variability Over The Andes, Jonathan Pugmire, Neal Criddle, Michael J. Taylor, P. D. Pautet, Yucheng Zhao

Jonathan Pugmire

The Andes region is an excellent natural laboratory for investigating gravity wave influences on the Upper Mesospheric and Lower Thermospheric (MLT) dynamics. The instrument suite that comprised the very successful Maui-MALT program was recently re-located to a new Andes Lidar Observatory (ALO) located at Cerro Pachon, Chile to obtain in-depth seasonal measurements of MLT dynamics over the Andes mountains. As part of the instrument set the Utah State University CEDAR Mesospheric Temperature Mapper (MTM) has operated continuously since August 2009 measuring the near infrared OH(6,2) band and the O2(0,1) Atmospheric band intensity and temperature perturbations. This poster focuses on an …


Seasonal Variations Of Relative Neutral Densities Between 45 And 90 Km Determined From Usu Rayleigh Lidar Observations, David Barton, Vincent B. Wickwar, Leda Sox, Joshua P. Herron Jun 2014

Seasonal Variations Of Relative Neutral Densities Between 45 And 90 Km Determined From Usu Rayleigh Lidar Observations, David Barton, Vincent B. Wickwar, Leda Sox, Joshua P. Herron

Posters

A Rayleigh-scatter lidar operated at the Atmospheric Lidar Observatory (ALO; 41.7°N, 111.8°W), part of Center for Atmospheric and Space Sciences (CASS) on the campus of Utah State University (USU), collected extensive data between 1993 and 2004. From the Rayleigh lidar photon-count profiles, relative densities were determined throughout the mesosphere, from 45 to 90 km. Using these relative densities three climatologies were derived, each using a different density normalization at 45 km. The first normalized the relative densities to a constant; the second to the NRL-MSISe00 empirical model which has a strong annual component; and the third to the CPC analyses …


Midlatitude Mesospheric Temperature Anomalies During Major Ssw Events As Observed With Rayleigh-Scatter Lidar, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron Jun 2014

Midlatitude Mesospheric Temperature Anomalies During Major Ssw Events As Observed With Rayleigh-Scatter Lidar, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron

Graduate Student Posters

While the mesospheric temperature anomalies associated with Sudden Stratospheric Warmings (SSWs) have been observed extensively in the polar regions, observations of these anomalies at midlatitudes are sparse. 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 a very dense set of temperature data for 11 years, from 1993 through 2004. The temperatures derived from these data extended over the mesosphere, from 45 to 90 km. This work focuses on the extensive Rayleigh lidar observations made during seven …


Rayleigh Scatter Lidar Observations Of The Midlatitude Mesosphere's Response To Sudden Stratospheric Warmings, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron May 2014

Rayleigh Scatter Lidar Observations Of The Midlatitude Mesosphere's Response To Sudden Stratospheric Warmings, Leda Sox, Vincent B. Wickwar, Chad Fish, Joshua P. Herron

Leda Sox

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 a very dense set of temperature data for 11 years, from 1993 through 2004. The temperatures derived from these data extended over the mesosphere, from 45 to 90 km. This work will focus on the extensive Rayleigh lidar observations made during the seven major SSW events that occurred between 1993 and 2004. In order to determine the characteristics of the midlatitude mesospheric temperatures during SSWs, comparisons were made …


Potential For Measurement Of Mesospheric Ozone Density From Overdense Meteor Trains With A Monostatic Meteor Radar, Reynold E. Sukara Dec 2013

Potential For Measurement Of Mesospheric Ozone Density From Overdense Meteor Trains With A Monostatic Meteor Radar, Reynold E. Sukara

Electronic Thesis and Dissertation Repository

Thermally ablating meteoroids, colliding with the Earth’s atmosphere, leave a high temperature trail containing extremely energetic metallic ions and electrons. A well recognized, but unresolved, anomaly associated with ambipolar diffusion of meteor trains, which is more dominant in overdense meteors, takes place in the initial post-adiabatic train expansion. In this work, a newly proposed mechanism explaining this anomaly involves hyperthermal chemical reactions is presented. Data from the SKiYMET meteor radar system, deployed at latitudinally dispersed locations, were used to determine ozone density in the upper atmosphere by analyzing diffusion of overdense meteor trains. The results obtained in this study are …


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 Dec 2013

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. …


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 Oct 2013

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 …


Midlatitude, Rayleigh-Mie-Raman Lidar For Observations From 15 To 120 Km, Vincent B. Wickwar, Leda Sox, Joshua P. Herron, Matthew T. Emerick Aug 2013

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.


Electron Loss And Meteoric Dust In The Mesosphere, M. Friedrich, M. Rapp, T. Blix, U. P. Hoppe, K. Torkar, S. Robertson, S. Dickson, Kristina Lynch Oct 2012

Electron Loss And Meteoric Dust In The Mesosphere, M. Friedrich, M. Rapp, T. Blix, U. P. Hoppe, K. Torkar, S. Robertson, S. Dickson, Kristina Lynch

Dartmouth Scholarship

No abstract provided.


Characterization Of An Axially Sampling Time-Of-Flight Mass Spectrometer For Upper Atmospheric Measurements, Addison E. Everett, Scott Schicker, Mike Watson, Wayne Sanderson, Dalon Work, Cameron Weston, James Dyer, Erik Syrstad May 2012

Characterization Of An Axially Sampling Time-Of-Flight Mass Spectrometer For Upper Atmospheric Measurements, Addison E. Everett, Scott Schicker, Mike Watson, Wayne Sanderson, Dalon Work, Cameron Weston, James Dyer, Erik Syrstad

Graduate Student Posters

The mesosphere/lower thermosphere (MLT) lies between the turbulent mixing and diffusive layers of the earth’s upper atmosphere. Temperatures in this region are varied and include the coldest region of the earth’s atmosphere, the mesopause. Too high for aircraft and too low for satellites, the only method of direct access to the MLT is by sounding rocket for periods of at most a few minutes. Because of this, the MLT is the most difficult region of the earth’s atmosphere to access and is therefore the least understood region of the earth’s atmosphere. Accurate in-situ measurements of MLT species are important for …


Investigating Mountain Waves In Mtm Image Data At Cerro Pachon, Chile, Neal R. Criddle, M. J. Taylor, P.-D. Pautet, Y. Zhao, G. Swenson, A. Liu Jan 2012

Investigating Mountain Waves In Mtm Image Data At Cerro Pachon, Chile, Neal R. Criddle, M. J. Taylor, P.-D. Pautet, Y. Zhao, G. Swenson, A. Liu

Neal R Criddle

Gravity waves are important drivers of chemical species mixing, energy and momentum transfer into the MLT (~80 - 100 km) region. As part of a collaborative program involving instruments from several institutions Utah State University has operated a Mesospheric Temperature Mapper (MTM) at the new Andes Lidar Observatory (ALO) on Cerro Pachon (30.2°S, 70.7°W) Since August 2009. A primary goal of this program is to quantify the impact of mountain waves on the MLT region. The Andes region is an excellent natural laboratory for investigating gravity wave influences on the MLT region, especially the study of mountain waves, created by …


Repeatability Of The Seasonal Variations Of Ozone Near The Mesopause From Observations Of The 11.072-Ghz Line, Alan E. E. Rogers, P. P. Erickson, V. L. Fish, J. J. Kittredge, S. S. Danford, J. M. Marr, Martina Arndt, J. Sarabia, D. Costa, S. K. May Jan 2012

Repeatability Of The Seasonal Variations Of Ozone Near The Mesopause From Observations Of The 11.072-Ghz Line, Alan E. E. Rogers, P. P. Erickson, V. L. Fish, J. J. Kittredge, S. S. Danford, J. M. Marr, Martina Arndt, J. Sarabia, D. Costa, S. K. May

Physics Faculty Publications

Ground-based observations of the 11.072-GHz line of ozone were made from January 2008 through the middle of September 2011 to estimate the maximum in the nighttime ozone in the upper mesosphere at an altitude of about 95 km for a region centered at 38°N, 290°E. The measurements show seasonal variation with a high degree of repeatability with peaks in ozone concentration about a month following each equinox. A significant increase in ozone concentration above the yearly trend occurred in 2010 from mid-November until the end of December, which the authors attribute to delay in the start of the meridional circulation …


A New Mass Spectrometer For Upper Atmospheric Measurements In The Auroral Region, Addison E. Everett, James S. Dyer, Mike Watson, Wayne Sanderson, Scott Schicker, Dalon Work, Christopher J. Mertens, Scott M. Bailey, Erik A. Syrstad Dec 2011

A New Mass Spectrometer For Upper Atmospheric Measurements In The Auroral Region, Addison E. Everett, James S. Dyer, Mike Watson, Wayne Sanderson, Scott Schicker, Dalon Work, Christopher J. Mertens, Scott M. Bailey, Erik A. Syrstad

Graduate Student Posters

We have previously presented a new rocket-borne time-of-flight mass spectrometer (TOF-MS) for measurements in the mesosphere / lower thermosphere (MLT). Traditionally, mass spectrometry in the MLT has been difficult, mainly due to the elevated ambient pressures of the MLT and high speeds of a sounding rocket flight, which affect the direct sampling of the ambient atmosphere and spatial resolution. The TOF-MS is a versatile, inherently adaptable, axial-sampling instrument, capable of operating in a traditional TOF mode or in a multiplexing Hadamard-transform mode where high spatial resolution is desired. To minimize bow shock effects at low altitudes (~70-110km), the ram surface …


Mesosphereic Temperature Variability And Seasonal Characteristics Over The Andes, Jonathan R. Pugmire, Yucheng Zhao, Michael J. Taylor, Dominique Pautet May 2011

Mesosphereic Temperature Variability And Seasonal Characteristics Over The Andes, Jonathan R. Pugmire, Yucheng Zhao, Michael J. Taylor, Dominique Pautet

Jonathan Pugmire

The Utah State University CEDAR Mesospheric Temperature Mapper (MTM) is a high-quality CCD imager capable of remote sensing faint optical emissions from the night sky to determine mesospheric temperature and its variability at an altitude of ~87 km. The MTM was operated at the new Andes Lidar Observatory (ALO)located at Cerro Pachon, Chile (30.2° S, 70.7° W) since August 2009 to investigate the seasonal characteristic of the mesopause at mid-latitudes. Measurement were made alongside a powerful lidar capable of height sounding the mesosphere. In this study, the MTM data have been analyzed to determine night to night variability and seasonal …


Early Observations Of The Middle Atmosphere Above Usu With The World’S Most Sensitive Lidar, Lance W. Petersen, Marcus J. Bingham, Vincent B. Wickwar, Joshua P. Herron Apr 2011

Early Observations Of The Middle Atmosphere Above Usu With The World’S Most Sensitive Lidar, Lance W. Petersen, Marcus J. Bingham, Vincent B. Wickwar, Joshua P. Herron

Posters

Extensive measurements have been made of the upper atmosphere by satellites and the lower atmosphere is measured twice daily by weather balloons. In contrast, the middle atmosphere is a difficult area to measure and therefore has been much less extensively studied. We are currently upgrading an old lidar system to a new system that will be 70 times more sensitive, making this the most sensitive lidar of its kind in the world. The upgrade consists of combining the outputs of 18 and 24 watt Nd:YAG lasers; implementing an optical chain to detect backscattered light using an existing large, four-mirror telescope; …


Seasonal Variability And Dynamics Of Mesospheric Gravity Waves Over The Andes, Neal R. Criddle, M. J. Taylor, P.-D. Pautet, Y. Zhao Jan 2011

Seasonal Variability And Dynamics Of Mesospheric Gravity Waves Over The Andes, Neal R. Criddle, M. J. Taylor, P.-D. Pautet, Y. Zhao

Neal R Criddle

The ALO is a new facility developed for atmospheric research, located at the foot of the Andes mountain range in Cerro Pachon, Chile (30.2°S, 70.7°W). As part of a collaborative program, Utah State has a Mesospheric Temperature Mapper (MTM) on site, which is used to study short period gravity wave dynamics and temperature variations in the mesosphere-lower thermosphere region. The MTM began taking measurements of the OH(6,2) and O2(0,1) spectral bands in August 2009 and a complete profile of seasonal variation in gravity wave characteristics has been created for August 2009 through August 2010 using the OH(6,2) Band. The primary …


Statistical Analysis Of The Usu Lidar Data Set With Reference To Mesospheric Solar Response And Cooling Rate Calculation, With Analysis Of Statistical Issues Affecting The Regression Coefficients, Troy Alden Wynn Dec 2010

Statistical Analysis Of The Usu Lidar Data Set With Reference To Mesospheric Solar Response And Cooling Rate Calculation, With Analysis Of Statistical Issues Affecting The Regression Coefficients, Troy Alden Wynn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Though the least squares technique has many advantages, its possible limitations as applied in the atmospheric sciences have not yet been fully explored in the literature. The assumption that the atmosphere responds either in phase or out of phase to the solar input is ubiquitous. However, our analysis found this assumption to be incorrect. If not properly addressed, the possible consequences are bias in the linear trend coefficient and attenuation of the solar response coefficient.

Using USU Rayleigh lidar temperature data, we found a significant phase offset to the solar input in the temperatures that varies ±5 years depending on …


The First Ten Months Of Investigation Of Gravity Waves And Temperature Variability Over The Andes, Jonathan Pugmire, Neal Criddle, Michael J. Taylor, P. D. Pautet, Yucheng Zhao Oct 2010

The First Ten Months Of Investigation Of Gravity Waves And Temperature Variability Over The Andes, Jonathan Pugmire, Neal Criddle, Michael J. Taylor, P. D. Pautet, Yucheng Zhao

Graduate Student Posters

The Andes region is an excellent natural laboratory for investigating gravity wave influences on the Upper Mesospheric and Lower Thermospheric (MLT) dynamics. The instrument suite that comprised the very successful Maui-MALT program was recently re-located to a new Andes Lidar Observatory (ALO) located at Cerro Pachon, Chile to obtain in-depth seasonal measurements of MLT dynamics over the Andes mountains. As part of the instrument set the Utah State University CEDAR Mesospheric Temperature Mapper (MTM) has operated continuously since August 2009 measuring the near infrared OH(6,2) band and the O2(0,1) Atmospheric band intensity and temperature perturbations. This poster focuses on an …


Mesospheric Atmospheric Gravity Wave Properties Derived From Rayleigh-Scatter Lidar Observations Above Logan, Utah, Durga Kafle May 2009

Mesospheric Atmospheric Gravity Wave Properties Derived From Rayleigh-Scatter Lidar Observations Above Logan, Utah, Durga Kafle

Posters

Approximately 900 nights of observations with a Rayleigh-scatter lidar at Utah State University’s Atmospheric Lidar Observatory (41.7°N, 111.8°W, 1.47 km above sea level), spanning the 11-year period from late 1993 through 2004, have been reduced to derive nighttime temperature and relative density profiles between 45 and 90 km. Of these, 150 profiles that extend to 90 km or above were used in this work, which is based mainly on relative density data with 3-km altitude resolution and 1-hour temporal resolution. This is, we believe, the first comprehensive study of monochromatic gravity waves using Rayleigh-Scatter lidar observations extending through the entire …


Rayleigh-Lidar Observations Of Mesospheric Instabilities, Gabriel C. Taylor, Durga N. Kafle, Vincent B. Wickwar Apr 2009

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 …


Large-Amplitude Temperature Waves In The Upper Atmosphere, Jarron Lembke, Vincent B. Wickwar Apr 2008

Large-Amplitude Temperature Waves In The Upper Atmosphere, Jarron Lembke, Vincent B. Wickwar

Posters

Recent LIDAR research at USU found a noctilucent cloud (NLC) near the minimum of a large-amplitude temperature wave in the upper mesosphere. Such a large-amplitude wave had not been seen previously. Initial analysis suggested that this wave might be related to the diurnal tide, but greatly amplified. This research set out to learn whether these waves are a common feature. Large waves or temperature “bumps” exceeding 10 K were found in more than half the observations. A later stage will be to see if they are linked to the tides.