Editing Bubble ring (section)

===Buoyancy induced toroidal bubbles===
As an air bubble rises, there is a difference in pressure between the top and bottom of the bubble. The higher pressure at the bottom of the bubble pushes the bubble's bottom surface up faster than the top surface rises. This creates a fluid jet that moves up through the center of the bubble. If the fluid jet has enough energy, it will puncture the top of the bubble and create a bubble ring. Because of the motion of the fluid moving through the center of the bubble, the bubble begins to rotate. This rotation moves the fluid around the bubble creating a toroidal vortex. If the surface tension of the fluid interface or the viscosity of the liquid is too high, then the liquid jet will be more broad and will not penetrate the top of the bubble. This results in a spherical cap bubble.<ref>{{cite journal|last=Chen|first=Li|author2=Suresh V. Garimella|author3=John A. Reizes|author4=Eddie Leonardi|title=The development of a bubble rising in a viscous liquid|journal=Journal of Fluid Mechanics|year=1999|volume=387|issue=1|pages=61–96|doi=10.1017/s0022112099004449|bibcode = 1999JFM...387...61C |s2cid=18934972 }}<!--|accessdate=15 October 2013--></ref> Air bubbles with a diameter greater than about two centimeters become toroidal in shape due to the pressure differences.<ref>{{Cite journal |title=Ring Bubbles of Dolphins |author1=Ken Marten |author2=Karim Shariff |author3=Suchi Psarakos |author4=Don J. White |journal=Scientific American |volume=275 |issue=2 |pages=82–87 |url=http://www.sciamdigital.com/index.cfm?fa=Products.ViewIssuePreview&ARTICLEID_CHAR=D0CD2470-180D-4C42-88B6-654E90AB55D |bibcode=1996SciAm.275b..82M |year=1996 |doi=10.1038/scientificamerican0896-82 |pmid=8693325 |access-date=2010-08-02 |archive-url=https://web.archive.org/web/20191218103217/http://www.sciamdigital.com/index.cfm?fa=Products.ViewIssuePreview&ARTICLEID_CHAR=D0CD2470-180D-4C42-88B6-654E90AB55D |archive-date=2019-12-18 |url-status=dead |url-access=subscription }}.</ref>