  The interpretation of molecular-line data in terms of hydro dynamical
simulations of planet-disk interactions fosters new hopes for the indirect
detection of protoplanets. In a model-independent approach, embedded
protoplanets should be found at the roots of abrupt Doppler flips in velocity
centroid maps. However, the largest velocity perturbation known for an unwarped
disk, in the disk of HD100546, leads to a conspicuous Doppler flip that
coincides with a thick dust ring, in contradiction with an interpretation in
terms of a >~ 1Mjup body. Here we present new ALMA observations of the
12CO(2-1) kinematics in HD\,100546, with a factor of two finer angular
resolutions. We find that the disk rotation curve is consistent with a central
mass 2.1 < M* /Msun < 2.3, and that the blue-shifted side of the Doppler flip
is due to vertical motions, reminiscent of the disk wind proposed previously
from blue-shifted SO lines. We tentatively propose a qualitative interpretation
in terms of a surface disturbance to the Keplerian flow, i.e. a disk eruption,
driven by an embedded outflow launched by a ~10Mearth body. Another
interpretation involves a disk-mass-loading hot-spot at the convergence of an
envelope accretion streamer.
