Antarctic mesospheric temperature estimation using the Davis mesosphere‐stratosphere‐troposphere radar

Abstract

[1] This paper presents the first Antarctic meteor radar temperature estimates. These temperatures have been derived from meteor diffusion coefficients using two techniques: pressure model and temperature gradient model. The temperatures are compared with a temperature model derived using colocated OH spectrometer measurements and Northern Hemisphere rocket observations. Pressure model temperatures derived using rocketderived pressures show good agreement with the temperature model, while those derived using Mass Spectrometer and Incoherent Scatter (MSIS) and CIRA model pressures show good agreement in winter but poor agreement in summer. This confirms previous studies suggesting the unreliability of high-latitude CIRA pressures. The temperature gradient model temperatures show good agreement with the temperature model but show larger fluctuations than the pressure model temperatures. Meteor temperature estimates made during the Southern delta-Aquarids meteor shower are shown to be biased, suggesting that care should be taken in applying meteor temperature estimation during meteor showers. On the basis of our results we recommend the use of the pressure model technique at all sites, subject to determination of an appropriate pressure model.

Change in turbopause altitude at 52 and 70° N

“…where P is the neutral pressure and K 0 is the zero field mobility of the ions in the trail (here we assume , 1961;Chilson et al, 1996;Cervera and Reid, 2000;Holdsworth et al, 2006). The pressure, P , was obtained from NRLMSISE-00 for consistency with the turbulence calculations.…”

Neutral atmosphere temperature trends and variability at 90 km, 70 °N, 19 °E, 2003–2014

“…In this study we used the value for K 0 of 2.4 × 10 −4 m 2 s −1 V −1 , in accordance e.g. with Holdsworth et al (2006). Pressure values were derived from atmospheric densities obtained from falling sphere measurements appropriate for 70 • N, combining those of Lübken and von Zahn (1991) and Lübken (1999), previously used by e.g.…”

On the validity of the ambipolar diffusion assumption in the polar mesopause region

“…The All-Sky Interferometric Meteor Radar (SKiYMET) system is a multi-channel coherent receiver pulsed radar capable of observing a wide range of parameters through the detection and analysis of faint meteors (see Hocking et al, 2001, for details).…”

“…Each method of temperature estimation that uses ablating meteors requires the assumption that ambipolar diffusion alone governs the decay of the underdense meteor echoes. However, alternative mechanisms exist, which can also affect the decay rate (Dyrud et al, 2001;Havnes and Sigernes, 2005;Dimant and Oppenheim, 2006a,b;Holdsworth et al, 2006).…”