"逐渐加速上升" can be translated into English as "gradually accelerating upwards" or "increasingly accelerating in an upward direction".
In more concise or context-specific expressions, you might also use:
"rising with increasing acceleration"
"accelerating as it ascends"
The choice depends on the specific context and the level of formality required. For most general purposes, "gradually accelerating upwards" is clear and effective.