# Nonlocal closure

From AMS Glossary

## nonlocal closure

A method of approximating unknown turbulence quantities, such as covariances, by sums or integrals (over the whole domain of turbulence) of known quantities.

This mimics the effects of a spectrum of eddy sizes causing mixing from various distances. Examples are transilient turbulence theory and spectral diffusivity theory.

*See*nonlocal flux, nonlocal mixing.