Currents in Primary

OK, So, a noobish question to be certain, but here it is: In the primary, amidst the frenzied activity of the yeasties, what, on a mechanical level, contributes to the turbulence, and the, for want of a more accurate description, convection currents? I realize, or suspect, that this is not in fact a thermal current, although it mimics one in its rise and fall pattern. (<~~Longest run-on sentence in history?) What then is actually occuring, again, mechanically. Chemically, I know, but I cannot wrap my head around, if this is not a thermal activity, what is causing the considerable turbulence? Dynamic changes in visosity? Osmolarity? Thank you.

I always assumed it had something do to with the C02 being produced.

Well, Im not saying its not, since I obviously dont know what the answer is, but the way I see it, if it was CO2 related, I would expect to see some sort of pnuematic activity within the Brew itself in the form of visible bubbles, but as I understand the process, (may be totally wrong) the CO2 release is occuring at the suface only, which, to me, wouldnt explain the "systemic" turbulence effect.

Well, my theory doesnt make sense either, its not like the yeasties are waiting on line to get to the surface, dumping their CO2 and politely moving out of the way so that the next group can purge. So, maybe it is CO2 release in solution, but we don't see actual bubbles because it's occuring on a microscopic level?

Experts?

Fermentation is exothermic so I believe they are indeed convective currents.

orly? Well, that certainly would jibe with the appearance of the currents. Also why my brew temp is > Ambient.

I don't know , but it looks really cool and if you shine a flashlight into it there pattern changes?

IT"S ALIVE!!!!!

Heat and differences thereof or what jkarp has already said. Think of it as a small scale version of the Earth's ocean currents.

Perhaps it has something to do with density differences within the solution.

Lancaster PA.

And, Density variation was one theory i had when I suggested Viscosity differences as a possiblity.

It does, in fact, look very cool. So alive, self perpetuating biosphere of yeasty goodness. Mmmm, Get in mah belly!!