The Reynolds number dependency of intermittency for 2D turbulence is studied
in a flowing soap film. The Reynolds number used here is the Taylor microscale
Reynolds number R_{\lambda}, which ranges from 20 to 800. Strong intermittency
is found for both the inverse energy and direct enstrophy cascades as measured
by (a) the pdf of velocity differences P(\delta u(r)) at inertial scales r, (b)
the kurtosis of P(\partial_x u), and (c) the scaling of the so-called
intermittency exponent \mu, which is zero if intermittency is absent. Measures
(b) and (c) are quantitative, while (a) is qualitative. These measurements are
in disagreement with some previous results but not all. The velocity
derivatives are nongaussian at all R_{\lambda} but show signs of becoming
gaussian as R_{\lambda} increases beyond the largest values that could be
reached. The kurtosis of P(\delta u(r)) at various r indicates that the
intermittency is scale dependent. The structure function scaling exponents also
deviate strongly from the Kraichnan prediction. For the enstrophy cascade, the
intermittancy decreases as a power law in R_{\lambda}. This study suggests the
need for a new look at the statistics of 2D turbulence.Comment: 15 pages, 11 figure