Scanning iron temperature lidar for mesopause temperature observation

Abstract

We introduce a new method for temperature profile measurements in the mesopause region in the altitude range from 80 to 105 km. A frequency-doubled narrowband alexandrite laser is used to scan the iron resonance line at 386 nm. The isotopic shifts of the iron isotopes and the laser bandwidth are derived by the measurement itself. Neglecting the minor isotopes results in large temperature errors up to 28 K. We discuss the derived temperatures in comparison with results of our potassium temperature lidar. The iron lidar-derived temperatures have typically a statistical error of 0.4 K and vary by less than 10 K, which is due to the daily natural variation. The all-solid-state system, which is compact, can be containerized and deployed at remote locations.