An Advanced Review of the Relationships between Sahel Precipitation and Climate Indices: A Wavelet Approach
Figure 3
Cross wavelet spectrum. (a) Nino 3.4, (b) Nino 3.4, (c) Atlantic Multidecadal Oscillation (AMO) and wavelet coherence, and (d) Atlantic Multi-decadal Oscillation (AMO). (In-phase, pointing right; anti-phase, pointing left; and leading by 90∘ pointing straight down; see text for details and interpretation). The thick contour enclosed regions are greater than 95% confidence for a red-noise process. The thin solid line indicates the “cone of influence,” where edge effects become important.
