Bug in thermal conductivity computation for Pringle version

[vancop]

In the computation of thermal conductivity using Pringle formula,
the first-layer value reads:
ztcond_i(ji,0)= rcdic + 0.09*s_i_b(ji,1) / &

MIN(-zeps,t_i_b(ji,1)-rtt) - &
0.011* ( t_i_b(ji,1) - rtt )

which is correct!!! Great!

However for layers 2, ..., N-1, the computation reads:
ztcond_i(ji,layer) = rcdic + 0.09*( s_i_b(ji,layer) &

+ s_i_b(ji,layer+1) ) / MIN(-zeps, &
t_i_b(ji,layer)+t_i_b(ji,layer+1)-2.0*rtt) - &
0.011* ( t_i_b(ji,layer) + t_i_b(ji,layer+1) - 2.0*rtt )

which is not that great, because there is a missing factor 0.5 factor... This should read:
ztcond_i(ji,layer) = rcdic + 0.09*( s_i_b(ji,layer) &

+ s_i_b(ji,layer+1) ) / MIN(-zeps, &
t_i_b(ji,layer)+t_i_b(ji,layer+1)-2.0*rtt) - &
0.011*0.5*( t_i_b(ji,layer) + t_i_b(ji,layer+1) - 2.0*rtt )

Thanks again to Fred Dupont for pointing out

A priori, the differences are small in terms of ice thickness.

However, I put priority as major, since this is a clear bug, easy to fix.

Si you soune,

Martin

[gm]

This correction has already be done in v3.3 See ticket #799 and the associated Changeset 2591

Gurvan