Variations of the temperatures in the mesopause and lower thermospheric region with solar activity Original Research Article

Temperature distributions with height (70–130 km) are constructed from EISCAT radar measurements at high latitudes and spectrophotometric measurements of hydroxyl emission (87 km), sodium (92 km) and of atomic oxygen emission of 557.7 nm (97–102 km) at mid latitudes for the period 1984–1998. It is revealed that the temperature dependence on solar activity at heights of 87 and 108 km is seasonal with negative correlation in winter and positive correlation in summer. Estimates of the long-term change of temperature for the specified period of observation are made.