Density and Ocean Circulation

Climate icon
Temperature and salinity control seawater's density. The weight of seawater determines whether it sinks or floats, helping to drive deep ocean circulation. At the sea surface, wind and waves move seawater — and the heat it carries — around our globe.

Understanding salinity helps us understand global patterns, including the circulation of water in the deep ocean. Together, salinity and temperature control density at the ocean surface. Thus, satellite salinity measurements are complementary to existing programs that monitor sea surface temperature. The resources on this page illuminate the connection between density and the ocean's motion, and the consequences to our climate.

Document cover page: teaching physical concepts in oceanography - 04
Convection
hands-on activity | PDF (27.0 MB)
Document cover page: teaching physical concepts in oceanography - 05
Convection Under Ice
hands-on activity | PDF (27.0 MB)
Cover page: density bags
Density Bags
hands-on activity
Document cover page:  seawater mixing and sinking
Density: Seawater Mixing & Sinking
hands-on activity | PDF (1.7 MB)
Document cover page: teaching physical concepts in oceanography - 03
Effect of Stratification on Mixing
hands-on activity | PDF (27.0 MB)
Document cover page: teaching physical concepts in oceanography - 01
Effects of Temperature & Salinity on Density & Stratification (Steps 1-4)
hands-on activity | PDF (27.0 MB)
Document cover page: teaching physical concepts in oceanography - 02
Effects of Temperature & Salinity on Density & Stratification (Steps 5-7)
hands-on activity | PDF (27.0 MB)
Susan Lozier
Finding the Link Between Ocean Density and Circulation
movie | MP4 (38.1 MB)
Cover page: go with the flow
Go With the Flow
online interactive
Document cover page: teaching physical concepts in oceanography - 06
Heat Flow and Latent Heat
hands-on activity | PDF (27.0 MB)
Susan Lozier
Importance of Salinity
movie | MP4 (1.6 MB)
Document cover page: liquid rainbow
Liquid Rainbow
hands-on activity | PDF (1.3 MB)
Visualization of ocean currents
Ocean Flows at Surface and 2000 Meters Below Sea Level
movie | MP4 (8.0 MB)
Cover page: ocean surface currents
Ocean Motion: Ocean Surface Currents
online interactive
Cover page: ocean surface winds
Ocean Motion: Ocean Surface Winds
online interactive
Global circulation
The Ocean: A Driving Force for Weather and Climate
movie | MP4 (45.6 MB)
Stephen Riser
Why Care About Ocean Salinity?
movie | MP4 (185.8 MB)

FAQs

Salinity changes a lot as you go deeper into the ocean. The satellite can only "see" the ocean surface, a very thin layer around a few centimeters.