Fig. 8.From: Secular trend of geomagnetic elements in the Indian regionPlot of the first difference of annual mean values of declination (D), horizontal component (H), and vertical component (Z), for all days at (a) Trivandrum, (b) Kodaikanal, (c) Annamalainagar, (d) Hyderabad, (e) Albag, and (f) Sabhawala, from 1958 to 2009.Back to article page