<p>Well the southern water tribe waterbending population has been increased greately. There were so many southern waterbenders during Book 2. Korra's parents, the rebels and all these people were waterbenders. I agree with Lumoshi and BumJun. The world is rebelancing itself. And as we know, airbending is the most spiritual bending art. So if the spiritual energy is shitfting, airbending will be the most prominent result.
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