Nighttime Na-D Emission Observed from a Polar Orbiting DMSP (Defense Meteorological Satellite Program) Satellite
Abstract
Limb scans of nighttime sodium doublet emission at 589 nm were performed globally from a sun-synchronous satellite during July 1979. The observations have provided a global description of variations in the emitting layer with latitude and altitude. The limb-scan data are consistent with the presence of a 10 km thick emitting layer near the 90 km peak of the sodium density in the northern midlatitude mesosphere in summer. At equatorial and southern latitudes, however, a narrower emission layer occurs 5-10 km lower, and the intensity is stronger by a factor of 3 or more. It appears likely that the shape of the Na-D emission profile is influenced by the altitude distributions of both sodium and ozone, the reactants that are necessary to produce the emission. The observed variability may be explained by a systematic seasonal mismatch in the altitude of the mesospheric density maxima for sodium and ozone, combined with a known threefold wintertime increase in sodium density. Keywords: Airglow; Global; Nightglow; Ozone; Sodium. (JHD)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1989
- Accession Number
- ADA213901
Entities
People
- Alice L. Newman
Organizations
- The Aerospace Corporation