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The streamlines are contours of $\psi$. Since $A<0$, the exact streamfunction is negative inside the rectangle and zero on its perimeter. It has one interior minimum, with closed anticlockwise streamlines: a broad northward interior flow returns southward along the west wall; flow is westward near the north edge and eastward near the south edge. The western parts of the streamlines are closely packed because the western boundary current is much faster.

The figure uses the exact ordinary differential equation solution, so it also remains consistent with both wall conditions when the asymptotic scale separation is only moderate. It depicts the stipulated dynamical model, not observed winds or a reconstruction of the source illustration.

To return the broad interior transport, the western boundary current has opposite sign and characteristic peakThe leading exponential profile retains the smaller interior offset, $v(0)\simeq (F_0/\beta )(1-L/{\delta }_W)\simeq -52.1\mathrm{m}{\mathrm{s}}^{-1}$. Because $\gamma L\simeq 0.593$ is not very small, the exact two-wall solution gives a more accurate linear-model peak:All three evaluations identify an intense southward western boundary current, with peak at $x=0,y=0$, of order tens of metres per second. They are predictions of the stated steady linear barotropic model. Nonlinear advection, stratification and the actual basin geometry could alter them substantially; the calculation does not establish that real Pluto winds attain these values.

Use the positive rotation-rate convention implicit in the northward planetary vorticity gradient. One Pluto day is $T_P=6.4\times 86400=552960\mathrm{s}$. At the equator,The width of the western boundary current is thereforeHere $b=a_p\pi /3\simeq 1244\mathrm{km}$ is the full meridional scale, and $L=a_p(50\pi /180)\simeq 1037\mathrm{km}$. For these data the exact exponents give ${\lambda }^{-1}\simeq 89.7\mathrm{km}$, $\lambda L\simeq 11.56$ and $\gamma L\simeq 0.593$. The western layer is narrow, but $\gamma L\ll 1$ is only marginal. The leading estimates below should therefore be distinguished from evaluation of the exact linear model.