Fractional Brownian Motion(fBM) ported to an NPM package for glslify. Also check out GLSL Noise Algorithms
npm install glsl-fbm
attribute vec3 position;
attribute vec2 uv;
uniform float time;
#pragma glslify: fbm = require(glsl-fbm)
void main() {
vec3 pos = position;
float height = fbm(vec3(uv, time));
pos.y += height;
gl_Position = uProjectionMatrix * uViewMatrix * uModelMatrix * vec4(pos, 1.0);
}