  Mrk 71/NGC 2366 is the closest Green Pea (GP) analog and candidate Lyman
Continuum (LyC) emitter. Recently, 11 LyC-leaking GPs have been detected
through direct observations of the ionizing continuum, making this the most
abundant class of confirmed LyC-emitters at any redshift. High resolution,
multi-wavelength studies of GPs can lead to an understanding of the method(s),
through which LyC escapes from these galaxies. The proximity of Mrk 71/NCG 2366
offers unprecedented detail on the inner workings of a GP analog, and enables
us to identify the mechanisms of LyC escape. We use 5825-7650{\AA} integral
field unit PMAS observations to study the kinematics and physical conditions in
Mrk 71. An electron density map is obtained from the [S II] ratio. A fortuitous
second order contamination by the [O II]3727 doublet enables the construction
of an electron temperature map. Resolved maps of sound speed, thermal
broadening, "true" velocity dispersion, and Mach number are obtained and
compared to the high resolution magneto-hydrodynamic SILCC simulations. Two
regions of increased velocity dispersion indicative of outflows are detected to
the north and south of the super star cluster, knot B, with redshifted and
blueshifted velocities, respectively. We confirm the presence of a faint broad
kinematical component, which is seemingly decoupled from the outflow regions,
and is fainter and narrower than previously reported in the literature. Within
uncertainties, the low- and high-ionization gas move together. Outside of the
core of Mrk 71, an increase in Mach numbers is detected, implying a decrease in
gas density. Simulations suggest this drop in density can be as high as ~4 dex,
down to almost optically thin levels, which would imply a non-zero LyC escape
fraction along the outflows... [abridged]
