The Atlantic Multidecadal Oscillation (AMO), also known as Atlantic Multidecadal Variability (AMV), is the theorized variability of the sea surface temperature (SST) of the North Atlantic Ocean on the timescale of several decades. While there is some support for this mode in models and in historical observations, controversy exists with regard to its amplitude, and whether it has a typical timescale and can be classified as an oscillation. There is also discussion on the attribution of sea surface temperature change to natural or anthropogenic causes, especially in tropical Atlantic areas important for hurricane development. The Atlantic multidecadal oscillation is also connected with shifts in hurricane activity, rainfall patterns and intensity, and changes in fish populations. Source: Wikipedia (en)