Right-handed rectangular coordinates

From Glossary of Meteorology

right-handed rectangular coordinates

Rectangular Cartesian coordinates in which the coordinates x, y, and z are measured along three mutually perpendicular axes such that a rotation of the positive x axis into the positive y axis will drive a right-handed screw in the direction of the positive z axis.

The Cartesian coordinates most often used in meteorology form a right-handed system: x increasing to east, y to north, z to zenith.