Temperature variations in the latitude band 45°N to 55°N. Temperature variations in the latitude band 45°N to 55°N on a (left) pressure and (right) geometrical altitude of 70 km. LIMA temperatures (black lines) are compared with a multivariate fit (red lines) consisting of carbon dioxide, ozone, and Ly-α. For comparison, a linear fit over the entire time period is also shown (green line). The orange curve shows the variation of Ly-α and the cyan curve shows the variation of ozone (right axis). The two squares mark temperatures in 1975 and 1976 which are ignored when fitting. After Lübken et al. ().