{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/21059"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/21059","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Iron and sodium Doppler/temperature lidar studies of the upper mesosphere","abstract":"Lidar measurements of mesospheric Fe were conducted at Urbana, Illinois, during four nights in late October 1989. The average Fe abundances, layer centroid heights and rms widths varied between 1.0-2.0 $\\times$ 10$\\sp{10}$ cm$\\sp{-2}$, 89.0-90.5 km and 3.2-4.1 km, respectively. The peak densities of the layer near 90 km varied between 15-25 $\\times$ 10$\\sp3$ cm$\\sp{-3}$. On three nights the formation and dissipation of three large sporadic Fe (Fe$\\sb{\\rm s}$) layers were observed.","abstract_html":"Lidar measurements of mesospheric Fe were conducted at Urbana, Illinois, during four nights in late October 1989. The average Fe abundances, layer centroid heights and rms widths varied between 1.0-2.0 $\\times$ 10$\\sp{10}$ cm$\\sp{-2}$, 89.0-90.5 km and 3.2-4.1 km, respectively. The peak densities of the layer near 90 km varied between 15-25 $\\times$ 10$\\sp3$ cm$\\sp{-3}$. On three nights the formation and dissipation of three large sporadic Fe (Fe$\\sb{\\rm s}$) layers were observed.","abstract_has_math":true,"creators":["Bills, Richard Earl"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Electrical Engineering","degree_department":null,"school":null,"contributors":["Gardner, Chester S."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T12:57:09Z","date_published":"2011-05-07T12:57:09Z","updated_at":"2026-07-22T22:25:17Z","subjects":["Engineering, Electronics and Electrical","Physics, Atmospheric Science","Physics, Optics"],"languages":["eng"],"rights":["Copyright 1991 Bills, Richard Earl"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9210745","(UMI)AAI9210745"],"render_values":[{"text":"AAI9210745","href":null,"code":true},{"text":"(UMI)AAI9210745","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/21059","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Gardner, Chester S."]},{"key":"dc:creator","label":"Author","values":["Bills, Richard Earl"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T12:57:09Z","10000-01-01","1991"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Electrical Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Engineering, Electronics and Electrical","Physics, Atmospheric Science","Physics, Optics"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1991 Bills, Richard Earl"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9210745","(UMI)AAI9210745","http://hdl.handle.net/2142/21059"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Lidar measurements of mesospheric Fe were conducted at Urbana, Illinois, during four nights in late October 1989. The average Fe abundances, layer centroid heights and rms widths varied between 1.0-2.0 $\\times$ 10$\\sp{10}$ cm$\\sp{-2}$, 89.0-90.5 km and 3.2-4.1 km, respectively. The peak densities of the layer near 90 km varied between 15-25 $\\times$ 10$\\sp3$ cm$\\sp{-3}$. On three nights the formation and dissipation of three large sporadic Fe (Fe$\\sb{\\rm s}$) layers were observed.","A new two-frequency lidar technique for measuring mesospheric Na temperature profiles is described. This system uses a stabilized cw single-mode dye laser oscillator (rms frequency jitter $<$1 MHz) followed by a pulsed dye power amplifier (140 MHz FWHM linewidth) which is pumped by an injection-seeded Nd:YAG laser. The laser oscillator is tuned to the two operating frequencies by observing the Doppler-free structure of the Na D$\\sb2$ fluorescence spectrum in a vapor cell. The lidar technique and the initial observations are described. Absolute temperature accuracies at the Na layer peak of better than $\\pm$3 K with a vertical resolution of 1 km and an integration period of approximately 5 min were achieved in this initial experiment.","Fourteen nights of Na temperature lidar data spanning 6 months were collected at Urbana, Illinois, using the two-frequency technique. The temperature structure over the 80-100 km region was highly variable due to the influence of gravity waves, tides, and sporadic layers (Na$\\sb{\\rm s}).$ Extreme temperatures of 140 K and 255 K were measured. A mesopause cooling rate of 9 K/month was exhibited from winter to summer at the mesopause height localized between 85 and 90 km. The temperature dependence of the Na column abundance is analyzed, and a 9 $\\times$ 10$\\sp7$ atoms/cm$\\sp2/$K Na abundance rate of change was observed from winter to summer. The rms perturbations, wave dynamics, and Brunt-Vaisala periods are also investigated.","The first observations of vertically resolved Na density, temperature, and wind profiles in the mesopause region were made using a new four-frequency Doppler/temperature lidar. The initial zonal wind and temperature observations were obtained with a profile resolution of 30 min and 1.5 km and rms accuracies of 12 m/s and 2 K. These measurements were conducted simultaneously with the medium frequency (MF) radar at the Urbana Atmospheric Observatory (40$\\sp\\circ$N, 88$\\sp\\circ$W) during the night of 14-15 March, 1991. Although both the lidar and radar wind measurements exhibited the same general trends, the velocity estimates differed by as much as 40 m/s at some times during the night.","Made available in DSpace on 2011-05-07T12:57:09Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9210745.pdf: 5863466 bytes, checksum: 362cfecf28b2d41cfad7a47afa52d4b0 (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:48:12Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:21:48-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"]},{"key":"dc:title","label":"Title","values":["Iron and sodium Doppler/temperature lidar studies of the upper mesosphere"]}]}],"canonical_facts":{"dc:contributor":["Gardner, Chester S."],"dc:creator":["Bills, Richard Earl"],"dc:date":["2011-05-07T12:57:09Z","10000-01-01","1991"],"dc:description":["Lidar measurements of mesospheric Fe were conducted at Urbana, Illinois, during four nights in late October 1989. The average Fe abundances, layer centroid heights and rms widths varied between 1.0-2.0 $\\times$ 10$\\sp{10}$ cm$\\sp{-2}$, 89.0-90.5 km and 3.2-4.1 km, respectively. The peak densities of the layer near 90 km varied between 15-25 $\\times$ 10$\\sp3$ cm$\\sp{-3}$. On three nights the formation and dissipation of three large sporadic Fe (Fe$\\sb{\\rm s}$) layers were observed.","A new two-frequency lidar technique for measuring mesospheric Na temperature profiles is described. This system uses a stabilized cw single-mode dye laser oscillator (rms frequency jitter $<$1 MHz) followed by a pulsed dye power amplifier (140 MHz FWHM linewidth) which is pumped by an injection-seeded Nd:YAG laser. The laser oscillator is tuned to the two operating frequencies by observing the Doppler-free structure of the Na D$\\sb2$ fluorescence spectrum in a vapor cell. The lidar technique and the initial observations are described. Absolute temperature accuracies at the Na layer peak of better than $\\pm$3 K with a vertical resolution of 1 km and an integration period of approximately 5 min were achieved in this initial experiment.","Fourteen nights of Na temperature lidar data spanning 6 months were collected at Urbana, Illinois, using the two-frequency technique. The temperature structure over the 80-100 km region was highly variable due to the influence of gravity waves, tides, and sporadic layers (Na$\\sb{\\rm s}).$ Extreme temperatures of 140 K and 255 K were measured. A mesopause cooling rate of 9 K/month was exhibited from winter to summer at the mesopause height localized between 85 and 90 km. The temperature dependence of the Na column abundance is analyzed, and a 9 $\\times$ 10$\\sp7$ atoms/cm$\\sp2/$K Na abundance rate of change was observed from winter to summer. The rms perturbations, wave dynamics, and Brunt-Vaisala periods are also investigated.","The first observations of vertically resolved Na density, temperature, and wind profiles in the mesopause region were made using a new four-frequency Doppler/temperature lidar. The initial zonal wind and temperature observations were obtained with a profile resolution of 30 min and 1.5 km and rms accuracies of 12 m/s and 2 K. These measurements were conducted simultaneously with the medium frequency (MF) radar at the Urbana Atmospheric Observatory (40$\\sp\\circ$N, 88$\\sp\\circ$W) during the night of 14-15 March, 1991. Although both the lidar and radar wind measurements exhibited the same general trends, the velocity estimates differed by as much as 40 m/s at some times during the night.","Made available in DSpace on 2011-05-07T12:57:09Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9210745.pdf: 5863466 bytes, checksum: 362cfecf28b2d41cfad7a47afa52d4b0 (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:48:12Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:21:48-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"],"dc:identifier":["AAI9210745","(UMI)AAI9210745","http://hdl.handle.net/2142/21059"],"dc:language":["eng"],"dc:rights":["Copyright 1991 Bills, Richard Earl"],"dc:subject":["Engineering, Electronics and Electrical","Physics, Atmospheric Science","Physics, Optics"],"dc:title":["Iron and sodium Doppler/temperature lidar studies of the upper mesosphere"],"dc:type":["text"],"thesis:degree_discipline":["Electrical Engineering"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:17Z"}