Dryland Vegetation Patterns

Klausmeier model: Turing instability creates spots, stripes, labyrinths

Step: 0 ⟨veg⟩: - ⟨water⟩: - Pattern: initializing
The Klausmeier (1999) model: ∂w/∂t = a − w − wn² + d_w∇²w; ∂n/∂t = wn² − bn + d_n∇²n. Water (w) diffuses fast, vegetation (n) diffuses slowly. Below a critical rainfall a_c, the uniform state is Turing-unstable, spontaneously forming patterns. Low rainfall → spots; intermediate → labyrinths; near transition → stripes.