The PIs will develop a novel middle atmosphere temperature lidar that uses broadband tunable solid-state lasers and mesospheric iron as the fluorescence tracer. This system will be rugged and reliable, capable of making observations day and night, and capable of being deployed at remote sites or operated from research aircraft. After its construction, the system will characterize the thermal structure of the middle atmosphere to study iron and calcium in the mesopause region, and study the influence of tides and planetary waves. These observations will substantially improve the limited knowledge of middle atmosphere temperatures, quantify the natural variability, provide crucial tests of middle atmosphere circulation models, and significantly enhance understanding of large scale waves and tides in this region. Finally, the Arctic temperature observations planned will be the first made of the mesopause region at extreme high latitudes.
