Figure 4From: Filtering ionosphere parameters to detect trends linked to anthropogenic effectsfoF2 residuals for Juliusruh (54.6° N, 13.4° E). foF2 residuals obtained considering foF2mod = a F10.72+ b F10.7 + c (red line) and considering foF2mod = a F10.7 + b (black line). Linear trends and their equation are also shown in the figure.Back to article page