Desert

Activation deals fire damage to other creatures in the aura. Because it affects creatures around you rather than only enemies, party positioning matters.

Sea

Choose one creature in the aura. It makes a Dexterity saving throw and takes lightning damage on a failure, with reduced damage on a success according to the feature.

Tundra

Chosen creatures in the aura gain temporary hit points. This is proactive durability rather than ordinary healing.

Bonus-action competition

Activating the aura costs a bonus action. Feats, two-weapon fighting, magic items and other subclass or multiclass abilities may compete for that same action.

The environment shapes later features too

Storm Soul, Shielding Storm and Raging Storm all inherit the chosen environment, so the 3rd-level choice influences the subclass beyond the initial aura.