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dc.contributor.advisorTwomey, Seanen_US
dc.contributor.authorMergenthaler, John Leland
dc.creatorMergenthaler, John Lelanden_US
dc.date.accessioned2013-04-18T09:28:30Zen
dc.date.available2013-04-18T09:28:30Zen
dc.date.issued1981en_US
dc.identifier.urihttp://hdl.handle.net/10150/282067en
dc.description.abstractThe effect of increased stratospheric dust on the polarization and intensity of sunlight scattered by the terrestrial atmosphere in the spectral region near the ultraviolet transmission cutoff is examined. Particular interest is given to radiation reflected to space or transmitted to the surface in the direction perpendicular to the incident solar beam in a plane containing the sun and the local vertical. Theoretical results are presented from radiative transfer calculations using a simple single scattering model and a four layer model in which ground reflection and multiple scattering were treated. Results show that the polarization state of transmitted radiation of .2975 μ for an incident solar zenith angle of 70° is sensitive to dust loading above 50 mb. The depolarization caused by a moderate increase in stratospheric dust loading is found to be roughly comparable to that caused by ground reflection and tropospheric aerosol. The polarization of light reflected to space is found to be very sensitive to high altitude dust scattering while being much less sensitive to other sources of depolarization. Results show that increasing the amount of stratospheric dust can cause either an increase or a decrease in the daily dosage of ultraviolet radiation at the surface, depending on the altitude profile of the dust, the latitude and the season. Preliminary experimental results or polarization monitoring by a ground-based instrument are presented and discussed. Sky light polarization ratios in the direction normal to the solar beam at .2975 μ and .300 μ based on data collected in the spring and summer of 1980 from the roof of the Physics-Atmospheric Sciences building on the campus of The University of Arizona are presented and discussed. The stratospheric dust problem is considered in terms of stratospheric aerosol enhancement resulting from volcanic activity.
dc.language.isoen_USen_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.subjectDust.en_US
dc.subjectAir -- Pollution.en_US
dc.subjectStratosphere.en_US
dc.subjectLight -- Scattering.en_US
dc.subjectUltraviolet radiation -- Measurement.en_US
dc.titleSOME MIDDLE ULTRAVIOLET RADIATIVE EFFECTS OF PARTICULATE POLLUTION IN THE STRATOSPHEREen_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.identifier.oclc8723078en_US
thesis.degree.grantorUniversity of Arizonaen_US
thesis.degree.leveldoctoralen_US
dc.identifier.proquest8207011en_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineAtmospheric Sciencesen_US
thesis.degree.namePh.D.en_US
dc.identifier.bibrecord.b1392140xen_US
refterms.dateFOA2018-08-28T03:36:56Z
html.description.abstractThe effect of increased stratospheric dust on the polarization and intensity of sunlight scattered by the terrestrial atmosphere in the spectral region near the ultraviolet transmission cutoff is examined. Particular interest is given to radiation reflected to space or transmitted to the surface in the direction perpendicular to the incident solar beam in a plane containing the sun and the local vertical. Theoretical results are presented from radiative transfer calculations using a simple single scattering model and a four layer model in which ground reflection and multiple scattering were treated. Results show that the polarization state of transmitted radiation of .2975 μ for an incident solar zenith angle of 70° is sensitive to dust loading above 50 mb. The depolarization caused by a moderate increase in stratospheric dust loading is found to be roughly comparable to that caused by ground reflection and tropospheric aerosol. The polarization of light reflected to space is found to be very sensitive to high altitude dust scattering while being much less sensitive to other sources of depolarization. Results show that increasing the amount of stratospheric dust can cause either an increase or a decrease in the daily dosage of ultraviolet radiation at the surface, depending on the altitude profile of the dust, the latitude and the season. Preliminary experimental results or polarization monitoring by a ground-based instrument are presented and discussed. Sky light polarization ratios in the direction normal to the solar beam at .2975 μ and .300 μ based on data collected in the spring and summer of 1980 from the roof of the Physics-Atmospheric Sciences building on the campus of The University of Arizona are presented and discussed. The stratospheric dust problem is considered in terms of stratospheric aerosol enhancement resulting from volcanic activity.


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