From the analysis of data on spectral dependence of geometric albedo, we determined the changes of the aerosol optical depth τ_α and relative concentration of methane γ with atmospheric pressure: lnτ_α = -0.720 + 1.507Δlnp (-2.2085 ≤ lnp ≤ -1.0018), lnτ_α = +1.225 +1.160Δlnp (-1.0018 ≤ lnp ≤ -0.0595), lnτ_α = +2.318 + 0.192Δlnp (-0.0595 ≤ lnp), γ = 0.0027 for Jupiter; lnτ_α = -0.846 + 1.598Δlnp (-3.3619 ≤ lnp ≤ -2.0575), lnτ_α = +1.238 + 1.342Δlnp (-2.0575 ≤ lnp ≤ -1.2074), lnτ_α = +2.379 + 0.722Δlnp (-1.2074≤ lnp ≤ -0.6501), lnτ_α = +2.781 + 0.326Δlnp (0.6501 ≤ lnp), γ = 0.0027 for Saturn; lnτ_α = -2.694 + 0.087Δlnp (+0.3685 ≤ lnp ≤ +1.2314), lnτ_α =-2.619+7.341Δlnp (+1.2314 ≤ lnp ≤ +1.7556), lnτ_α = +1.229 +0.956Δlnp (+1.7556 ≤ lnp) for Uranus; lnτ_α = -1.861 +1.248Δlnp (+0.3204 ≤ lnp ≤ +0.9051), lnτ_α = -1.131 + 0.347Δlnp (+0.9051 ≤ lnp) for Neptune; average values of the relative concentrations of methane: lnγ = –9.982 + 2.676Δlnp (0.3584 ≤ lnp ≤ 1.5445); lnγ = -9.738 + 2.561Δlnp (0.3237 ≤ lnp ≤ 1.6156), γ = 0.00382 (lnp ≥ 1.6156) and 0.00554 (lnp ≥ 1.6156) for Uranus and Neptune, respectively, (p in bars).