A comparison of mesospheric temperatures from the Canadian Middle Atmosphere Model and HALOE observations: Zonal mean and signature of the solar diurnal tide

Abstract

Currently climate models are being extended to the middle atmosphere in order to investigate climate sensitivity in that region. This paper presents a comparison between the Canadian Middle Atmosphere Model (CMAM) climatology and 9 years of HALOE temperature measurements for the middle atmosphere. The analysis shows an overall agreement throughout the entire middle atmosphere with discrepancies within 10 K and less in various areas for both equinox and solstice conditions. For historical purposes, the analysis also includes a comparison with the CIRA‐86 reference model. In this case, the results indicate a significant CIRA‐86 warm anomaly in the upper mesosphere over the tropics which is particularly pronounced during equinox. Further analysis of the HALOE sunrise and sunset occultation measurements with the CMAM has revealed the signature of diurnal tides.