Which hand signal is commonly used to indicate "ascend" during a dive?

The hand signal that indicates "ascend" during a dive is commonly recognized as a thumbs up. This gesture has become a universal sign within the scuba diving community, clearly communicating the intention to move upwards. The signal is simple and easily distinguishable underwater, which is essential in maintaining safe communication between divers in potentially challenging visibility conditions.

Using the thumbs up signal effectively conveys the message without the need for verbal communication, which is especially important underwater where sounds are muffled and not easily heard. Other signals may be confusing or require more interpretation, while the thumbs up signal is widely understood and quickly recognized by divers around the world. This clarity helps in ensuring that all members of the dive team are on the same page regarding their ascent, making the diving experience safer and more enjoyable.