Severe turbulence is turbulence in which the up and downward motions of the aircraft will experience vertical accelerations that exceed 1G.

重度湍流是指飞机上下运动将经历超过 1G 的垂直加速度的湍流。

Add those up, and I'd get the vertical acceleration.

把它们加起来， 我就会得到垂直加速度。

And the vertical acceleration is just the force of gravity.

垂直加速度为 只是重力。