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Abstract. We applied the equivalent homogeneous cloud approximation (EHCA) to the bounded cascade inhomogeneous absorbing clouds and defined their effective radiative properties. It is found that we have to introduce an effective singlescattering albedo in addition to an effective optical depth to treat the inhomogeneous absorbing clouds under the plane-parallel homogeneous cloud assumption. For an inhomogeneous absorbing cloud, a pair of the effective parameters can be estimated from each one of three possible pairs taken fi'om the area-averaged reflectance, transmittance and absorptance. We found that the behavior of these effective properties was quite similar to •hose observed ibr the inhomogeneous non absorbing clouds except, that two effective parameters were to be examined instead of only one e•ct, ive parameter for the nonabsorbing clouds. Empirical relations for both the effective optical depth and the single-s{:attering albedo were given as a function of the local mean opt•ical depth and relative local clo•d inhomogeneity. We showed tha[ tile effbctive sin/_;le-sca, tterin• albedo could not be properly introduced ,re(let t•he effe(:tiv(' thi(:kn(•ss approximation (ETA), which indicates an important ('on(:eptu•fi (tifi'eren(:e between the EHCA and the ETA. Finally, we discussed t)ossi})lc (:onsequenccs of the effective single-scattering albedo, defined in this st, udy, with respe(:t to the anomalous absorption phenomenon.

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