A theory of mine about the elemental calamities is that it might be due to whichever element is most prevalant in the shard that gets absorbed. While all of the elements would be there in some measure, it's probable that the shattered shards might have been aspected towards the various elements. Thus when they got absorbed, the landscape of the time was filled with a lot of aether of one type, which either outright caused it or at least made it an attractive option.