Correlation Angles and Inner Products: Application to a Problem from Physics

Figure 1

(a) 1870–1940. (b)1940–2010. The plots are for two different correlation measures among a set of four global climate indices—the diameter 𝐷=𝑀_1,𝑎 (in red) and the area 𝐴=𝑀_2,𝑎 (in blue) are defined in the text. Minima correspond to high correlation. The diameter 𝐷 plot shows 18 identified minima while the area 𝐴 plot shows 30. Comparisons are given in Table 1.

(a)

(b)