With the LIGO discoveries last year I thought about gravitational waves too. Having such a wave having effects visible with the naked eye would be huge. It would probably rip the planet apart.
Gravity is one of several forces that may act on what's going on, but the cause of the wave is the initial perturbation, which isn't gravity. Put another way, if I have a steady-state hydrostatic system, gravity waves won't just spring into existence. You need that initial push.
In this case, the initial push seems to be wind hitting a mountain and being forced up.
You need the medium, gravity, and 'push' to get a wave. Calling them <medium>-wave, or 'push'-wave doesn't really tell you anything useful, so they're called gravity-waves. An alternative would have been buoyancy-wave, but apparently this didn't catch on (buoyancy and gravity are really two sides of the same coin, anyway).
Buoyancy is related to density, which is independent of gravity. Check: buoyancy can exist in a non-inertial reference frame provided acceleration in a "downward" direction.
Also, you don't need gravity to be the force being acted against in order to form a wave. You can get impact waves in water at 0g because of surface tension.
It's really something that Akatsuki is doing amazing science after the trials and tribulations that satellite has been through. After failing orbital insertion around Venus, it went five years in heliocentric orbit to reposition itself for insertion around Venus again. The team ended up macguyvering its secondary attitude control jets[1] for a long burn (~20 min) that they weren't designed for, but it worked and allowed for a successful insertion--albeit in a non-ideal orbit with a 9 day period instead of the originally planned 1.25 days.
Fun fact: spiral galaxies' galactic arms are stationary waves. They don't spin like spokes on a wheel. Stars in the arms don't remain in them - every star traverses through the arms and the regions between them [1]. Indeed, correlations have been hypothesised between Earth's extinction events and our Sun's predicted passage through these arms [2].
Consulting https://en.wikipedia.org/wiki/Atmosphere_of_Venus the atmosphere is mainly CO2 and molecular nitrogen, neither of which reacts with sulfuric acid. The clouds are at 10km and up, so they don't interact much with the surface, which has a tallest mountain peak of 11km.
> The planet Venus is covered by thick clouds of sulfuric acid that move westwards because the entire upper atmosphere rotates much faster than the planet itself.
How the hell?! I get that the length of a Venus day is really long (243 Earth days), but why would the wind be rotating in the same direction but faster?
