Filtering ionosphere parameters to detect trends linked to anthropogenic effects

Earth, Planets and Space

Table 1 foF2 trend values (MHz/year) for Slough (51.5°N, 359.4°E)

foF2 trend values were estimated after filtering foF2 12-month running mean at 12 LT with F10.7 for the period beginning in 1960 and ending in 1986 (minimum between cycles 21 and 22), in 1989 (maximum of cycle 22), in 1996 (minimum between cycles 22 and 23), in 2000 (maximum of cycle 23), and in 2009 (minimum between cycles 23 and 24).