  We analyze the role played by temperature in QCD_3 by means of a dimensional
interpolating approach. Pure gauge QCD_3 is defined on a strip of finite width
L, which acts as an interpolating parameter between two and three dimensions. A
two-dimensional effective theory can be constructed for small enough widths
giving the same longitudinal physics as QCD_3. Explicit calculations of
T-dependent QCD_3 observables can thus be performed. The generation of a
deconfinig phase transition, absent in QCD_2, is proven through an exact
calculation of the electric or Debye mass at high T. Low and high T behaviors
of relevant thermodynamic functions are also worked out. An accurate estimate
of the critical temperature is given and its evolution with L is studied in
detail.
