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Full-Text Articles in Physics
Determination Of Horizontal And Vertical Structure Of A Novel Pattern Of Short Period Gravity Waves Imaged During Aloha-93, Michael J. Taylor, D. C. Fritts, J. R. Isler
Determination Of Horizontal And Vertical Structure Of A Novel Pattern Of Short Period Gravity Waves Imaged During Aloha-93, Michael J. Taylor, D. C. Fritts, J. R. Isler
All Physics Faculty Publications
An all‐sky CCD imager has been used to measure the properties of short period gravity waves present over the Hawaiian Islands during the ALOHA‐93 campaign. Observations of emissions from four different altitudes provided a capability to describe the vertical as well as the horizontal structure of the wave field. On several occasions during this campaign an unusual morphology wave pattern was detected that consisted of a group of small‐scale waves oriented in the same direction. These were most noticeable in the OI (557.7 nm) emission, altitude ∼96 km, and were usually observed in association with a larger scale gravity wave. …
Aloha-93 Measurements Of Intrinsic Agw Characteristics Using The Airborne Airglow Imager And Groundbased Na Wind/Temperature Lidar, G. R. Swenson, Michael J. Taylor, P. Espy, C. S. Gardner, X. Tao
Aloha-93 Measurements Of Intrinsic Agw Characteristics Using The Airborne Airglow Imager And Groundbased Na Wind/Temperature Lidar, G. R. Swenson, Michael J. Taylor, P. Espy, C. S. Gardner, X. Tao
All Physics Faculty Publications
Monochromatic Acoustic Gravity Waves (AGWs) with periods < 1 hour are a prevalent feature in the mesospheric airglow layers. These waves are important dynamically and energetically to the region where their temporal and spatial morphology are not well established. The purpose of this study is establish the intrinsic AGW characteristics over an extended region (as flown by the NCAR Electra aircraft) and to present the data in terms of the predicted spectral domain defined by the Brunt‐Vaisala frequency and the diffusive filtering limit proposed by Gardner [1994]. On October 21, 1993, observations were made from the NCAR Electra aircraft during a 6 hour flight in a large triangle N and W of Maui, for a integral distance of ∼3000 km. The entire area observed [∼1 M km²] had a monochromatic AGW propagating toward the NW and the western half had a SW propagating wave superimposed. These waves were also observed with the Michelson interferometer on the aircraft and an airglow imager at the Haleakala location during this time. Intrinsic phase velocities were computed where the Na Wind/Temperature (W/T) lidar at Haleakala provided a measure of the mean wind to compensate phase velocities observed with the imager. The data were tabulated and plotted in an AGW spectral reference frame and compared to cutoff conditions predicted by diffusive filtering theory.
Maximum Penetration Of Atmospheric Gravity Waves Observed During Aloha-93, G. R. Swenson, C. S. Gardner, Michael J. Taylor
Maximum Penetration Of Atmospheric Gravity Waves Observed During Aloha-93, G. R. Swenson, C. S. Gardner, Michael J. Taylor
All Physics Faculty Publications
Atmospheric Gravity Waves (AGWs) are subject to altitude propagation limits which are governed by the diffusion processes. Diffusion times and scales which exceed the wave period and wavelength define the limiting domain for AGWs. An expression is presented which defines the upper altitude limit to which AGWs can propagate given vertical diffusion constraints of the atmosphere. Airglow, lidar, and radar measurements are combined to characterize the intrinsic AGW parameters in the 80–105 km altitude region. A subset of AGWs (17) observed by airglow imagers during the ALOHA‐93 were made when simultaneous wind measurements were available and intrinsic wave parameters were …
Spectrometric And Imaging Measurements Of A Spectacular Gravity Wave Event Observed During The Aloha-93 Campaign, Michael J. Taylor, D. N. Turnbull, R. P. Lowe
Spectrometric And Imaging Measurements Of A Spectacular Gravity Wave Event Observed During The Aloha-93 Campaign, Michael J. Taylor, D. N. Turnbull, R. P. Lowe
All Physics Faculty Publications
During the ALOHA‐93 campaign coincident imaging and interferometric measurements of the near infrared and visible wavelength nightglow emissions were made from Haleakala Crater, Maui. On 10 October, 1993 a most unusual wave event was observed. This disturbance appeared as a sharp “front” followed by several conspicuous wave crests which progressed rapidly through the imager's field of view (180°). As the front passed overhead the interferometer detected a sudden jump in both the OH intensity (>50%) and its rotational temperature (∼20 K) with the temperature increase leading the intensity by almost 15 min. At the same time the imager registered …
Height Measurements Of Oi (557.7 Nm) Gravity Wave Structure Over The Hawaiian Islands During Aloha-93, Michael J. Taylor, G. R. Swenson, V. Taylor
Height Measurements Of Oi (557.7 Nm) Gravity Wave Structure Over The Hawaiian Islands During Aloha-93, Michael J. Taylor, G. R. Swenson, V. Taylor
All Physics Faculty Publications
During the ALOHA‐93 campaign simultaneous observations of gravity wave structure in the OI(557.7 nm) nightglow emission were made using two all‐sky CCD imagers; one located near the summit of Haleakala Crater, Maui and the other at Mauna Loa Observatory, Hawaii. On 19 October a set of bright, planar, monochromatic waves was imaged by both systems as it progressed rapidly over the Hawaiian Islands. Triangulation on these wave forms indicates a mean altitude of 95±2 km in good agreement with previous rocket soundings at mid‐latitudes. Two methods of triangulation were employed, both achieving similar results.
All-Sky Measurements Of Short Period Waves Imaged In The Oi (557.7 Nm), Na(589.2 Nm) And Near Infrared Oh And O2(0,1) Nightglow Emissions During The Aloha-93 Campaign, Michael J. Taylor, M. B. Bishop, V. Taylor
All-Sky Measurements Of Short Period Waves Imaged In The Oi (557.7 Nm), Na(589.2 Nm) And Near Infrared Oh And O2(0,1) Nightglow Emissions During The Aloha-93 Campaign, Michael J. Taylor, M. B. Bishop, V. Taylor
All Physics Faculty Publications
As part of the ALOHA‐93 campaign a high performance all‐sky CCD imaging system was operated at Haleakala Crater, Maui, to obtain novel information on the properties and sources of short period gravity waves over an extended height range ∼80–100 km. Sequential observations of the near infrared OH and O2(0,1) bands and the visible wavelength OI(557.7 nm) and Na(589.2 nm) line emissions have enabled a unique comparison of the morphology and dynamics of the wave motions and their occurrence frequency at each emission altitude to be made. Two major findings are: (a) the detection of significantly higher amounts of wave structure …