Salinity
Definition
Salinity refers to the concentration of dissolved salts in water, affecting buoyancy and equipment performance in scuba diving.
More on Salinity
Saltwater has higher salinity than freshwater, making divers more buoyant in oceans compared to lakes or quarries. This difference significantly impacts how much weight a diver needs to achieve neutral buoyancy. Divers switching between environments must adjust their weight systems accordingly. Salinity also affects buoyancy compensation devices (BCDs) and tank behavior. Understanding salinity is critical for proper dive planning and achieving optimal buoyancy control.
Frequently Asked Questions
Higher salinity increases water density, making you more buoyant. You'll need more weight in saltwater than in freshwater.
Not usually, but you will need less weight due to the lower density of freshwater. Always perform a weight check before diving.
The difference varies by diver and gear, but typically 2–6 pounds (1–3 kg) more weight is needed in saltwater.
Yes. Ocean salinity can vary by region and season. Divers in brackish water (mix of salt and fresh) should test buoyancy directly.
Most computers assume saltwater by default. For freshwater diving, ensure your device has an adjustable setting if needed.