  Results of deploying a Differential Image Motion Monitor (DIMM) and a DIMM
combined with a Multi-Aperture Scintillation Sensor (MASS/DIMM) are reported
for campaigns in 2011 and 2012 on the roof of the Polar Environment Atmospheric
Research Laboratory (PEARL). This facility is on a 610-m-high ridge at latitude
80 degrees N, near the Eureka weatherstation on Ellesmere Island, Canada. The
median seeing at 8-m elevation is 0.85 arcsec or better based on DIMM data
alone, but is dependent on wind direction, and likely includes a component due
to the PEARL building itself. Results with MASS/DIMM yield a median seeing less
than 0.76 arcsec. A semi-empirical model of seeing versus ground wind speed is
introduced which allows agreement between these datasets, and with previous
boundary-layer profiling by lunar scintillometry from the same location. This
further suggests that best 20 percentile seeing reaches 0.53 arcsec, of which
typically 0.30 arcsec is due to the free atmosphere. Some discussion for
guiding future seeing instrumentation and characterization at this site is
provided.
