I would like to go about making this effect, but don't know how

In some games, you’ll see a ripple effect in the air, or the general area. For example, Striker Class Skills | Black Desert Online - YouTube

For the most part, I looked around and saw a lot related to a glass part on the camera, along with a little tweaking of the FOV + a vignette, but the ripple effect really has me stumped at the moment.

I was messing with terrain water earlier and thought of this post, maybe you can make the camera do something with GUI like gaussian blur uses UIBlur in the Lighting tab. The water distorts the parts under it.

That was the best I could think of. Or you could go to this post and do what the commenter recommended, though not sure if it would work. Feedback on Double jump

Edit: Maybe UI viewport frames for the terrain water? I’m not familiar with viewport frames so idk.

The color of the sky depends on the watercolor in the terrain.