  We present EIS/Hinode & SUMER/SoHO joint observations allowing the first
spectroscopic detection of accelerating disturbances as recorded with coronal
lines in inter-plume and plume regions of a polar coronal hole. From
time-distance radiance maps, we detect the presence of propagating disturbances
in a polar inter-plume region with a period of 15 to 20 min and a propagation
speed increasing from 130+/-14 km/s just above the limb, to 330+/-140 km/s
around 160" above the limb. These disturbances can also be traced to originate
from a bright region of the on-disk part of the coronal hole where the
propagation speed was found to be in the range of 25+/-1.3 to 38+/-4.5 km/s,
with the same periodicity. These on-disk bright regions can be visualized as
the base of the coronal funnels. The adjacent plume region also shows the
presence of propagating disturbance with the same range of period but with
propagation speeds in the range of 135+/-18 to 165+/-43 km/s only. To our
knowledge, this result provides first spectroscopic evidence of acceleration of
propagating disturbances in the polar region close to the Sun (within 1.2 solar
radii). We suggest that the waves are likely either Alfv'enic or fast
magnetoacoustic in the inter-plume and slow magnetoacoustic in plume regions.
This may lead to the conclusion that inter-plumes are preferred channel for the
acceleration of the fast solar wind.
