Wetness, or rainfall, also varies systematically from the equator to the pole.
If you are reading this, you are probably familiar with the two-nuclide diagram commonly used to represent paired Be-10 and Al-26 data: This example is from a review article by Darryl Granger from 2006 (in GSA Special Paper 415) that gives a good description of what the diagram is and how it is supposed to work.
Basically, the diagram shows Be-10 concentration on the x-axis and the Al-26/Be-10 ratio on the y-axis, although commonly both quantities are shown in normalized units computed by dividing observed concentrations by the respective production rates at the sample site – this normalization allows plotting data from different sites, with different production rates, on the same axis.
Because these magnetic anomalies form at the mid-ocean ridges, they tend to be long, linear features (hence the name "linear magnetic anomalies") that are symmetrically disposed about the ridges axes.