pro ccm3_liquid_radiative_param_longwave_new, wl, lwp, re, tau, omega, g




ki=0.090361 ; according to Kiehl et al., Journal of Climate, June 1998, pg 1133.

    tau=((lwp)*ki)

; implement the ssa of Chou et al (1999) figure 1.

; compute the wave number
wn=(1./wl)*1.e4

if wn lt 500. then begin
omega=1.-(0.25+(((0.4-0.25)/(500.-100.))*(wn-100.)))
endif

if wn ge 500. and wn lt 1000. then begin
omega=1.-(0.4+(((0.35-0.4)/(1000.-500.))*(wn-500.)))
endif

if wn ge 1000. and wn lt 1200. then begin
omega=1.-(0.35+(((0.8-0.35)/(1200.-1000.))*(wn-1000.)))
endif

if wn ge 1200. then omega=0.15

;   omega=0.01

    ;g=0.5
if wn lt 400. then begin
    g=(0.2+(((0.6-0.2)/(400.-200.))*(wn-200.)))
endif

if wn ge 400. and wn lt 1000. then begin
    g=(0.6+(((0.85-0.6)/(1000.-400.))*(wn-400.)))
endif

if wn ge 1000. then g=0.8

return
end