# Boyden index

From AMS Glossary

## Boyden index

A measure of the mean thermodynamic stability in a layer beneath 700 mb.

The Boyden index is given by I-Z-T-200, where I is the Boyden index, Z is the 1000–700- mb thickness in dam, and T is the 700-mb temperature in °C.

Boyden, C. J. 1963. Meteor. Mag.. 92. 198–210.