Density-driven circulation in an estuary

This is a simple laboratory demonstration to show what happens to low-salinity (low density) estuary water when it enters the high-salinity (higher density) ocean. The low density estuarine water will float above the higher density seawater. This generates an average flow out of the estuary at the surface and an inflow of salty water near the bed, called “estuarine” or “density-driven” circulation.

[@nipuni_o601]

Thank you for the very clear explanation.

[@litvinenkoalexander5331]

very useful, thanks for your nice demo

[@mrsclancyschannel]

Your demos are fantastic! Thank you. My grade 2 students have been asking me about where oceans mix (or don't mix- they seem to think there's a straight line going down from the surface to the ocean and the oceans never mix together) and we tried to do a quick search in the middle of class but couldn't find anything that looked credible in the moment. These demos will be excellent to share with them!

[@jonathansharples8130]

It sounds like you have a very smart grade 2 class! Really pleased to see the lab experiment is useful for them.

[@vivekbind7292]

hello sir. you did a great work.
can you demonstrate the concept of brine rejection

[@jonathansharples8130]

There's a nice explanation here: en.wikipedia.org/wiki/Brine_rejection. It is something that happens when salt water freezes. The salts can fir within the ice matrix, so they are ejected from the ice as very salty brines. These are very dense, so they sink quickly - an important process at high latitudes when sea ice forms.

[@nikhilkayathwal7270]

Superb demonstration!!