HR: 15:10h
AN: SA42A-06    [PDF]
TI: Two Years of PMC Observations With OSIRIS on Odin
AU: * Petelina, S V
EM: svetlana@osirus.usask.ca
AF: Institute of Space and Atmospheric Studies, University of Saskatchewan, 116 Science Place, Saskatoon, SK S7N5E2 Canada
AU: Degenstein, D A
EM: degenstein@dansas.usask.ca
AF: Institute of Space and Atmospheric Studies, University of Saskatchewan, 116 Science Place, Saskatoon, SK S7N5E2 Canada
AU: Llewellyn, E J
EM: llewellyn@skisas.usask.ca
AF: Institute of Space and Atmospheric Studies, University of Saskatchewan, 116 Science Place, Saskatoon, SK S7N5E2 Canada
AU: Lloyd, N D
EM: lloyd@osirus.usask.ca
AF: Institute of Space and Atmospheric Studies, University of Saskatchewan, 116 Science Place, Saskatoon, SK S7N5E2 Canada
AB: The Odin research satellite, a joint Sweden, Canada, France and Finland mission, was launched in February 2001 into a sun-synchronous terminator orbit at an altitude of approximately 600 km, with the at ascending node 1800 LT. Its period is 96.7 min, and the maximum latitudinal coverage in the orbital plane is from 82.2 N to 82.2 S. Since spring 2001 the Optical Spectrograph and Infrared Imaging System (OSIRIS) instrument on Odin measures the atmospheric limb brightness by nodding between 6 km and 65 km (stratospheric mode), between 6 and 100 km (stratospheric-mesospheric mode), and between 65 km and 100 km (mesospheric mode). When in one of the last two modes, OSIRIS can detect Polar Mesospheric Clouds (PMC) by measuring the limb-scattered solar radiance from these clouds in the spectral range from 280 nm to 800 nm with a 1 nm resolution. Since the primary goal of OSIRIS is to study the stratospheric ozone, it normally scans the mesosphere once in every 8 days. The only exception is the Northern Hemisphere summer period (2 weeks in July), when OSIRIS operates in mesospheric mode about 80 persent of the time, and the remaining 20 percent are devoted to stratospheric-mesospheric measurements. During the last two years, OSIRIS has detected many PMC in both hemispheres. In this work we present their annual frequency of appearance, spatial and temporal distribution, average height and brightness. The broad spectral range of OSIRIS provides a unique opportunity to obtain PMC color information. In addition we compare cloud particle sizes calculated under the assumption of power and lognormal distributions of uniform spherical Mie scatterers made of ice.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0320 Cloud physics and chemistry
DE: 1600 GLOBAL CHANGE (New category)
SC: SPA - Aeronomy [SA]
MN: 2003 Fall Meeting