Swirling bubbles of white foam slowly circulate on the surface a Scottish river in a hypnotic, constantly changing pattern of organic shapes as a fast river current flows through a green, mossy gorge

north esk river esk stream dissolved organic carbon fresh water flowing river ripple froth whitewater water swirling foam gorge fishing moss foamy foaming float bubbles carbon turbulent shifting pollution flow surface surge salmon swirl floating spume bubble reflection circulate spiral movement contrast patterns change twist slow drift white cliff fast hypnotic organic current eddy