What Is Divergence?
When air spreads out from an area. Spreading high up pulls air up from below; spreading near the ground happens where air sinks. In technical terms: The horizontal divergence of the wind, du/dx + dv/dy, positive for net outflow; by continuity upper-level divergence over low-level convergence implies ascent and falling surface pressure.
Divergence In Plain English
When air spreads out from an area. Spreading high up pulls air up from below; spreading near the ground happens where air sinks.
The Technical Definition
The horizontal divergence of the wind, du/dx + dv/dy, positive for net outflow; by continuity upper-level divergence over low-level convergence implies ascent and falling surface pressure.
