Here's a little application for SH4 that will randomize the thermal attenuation effect values based on time of year. Since SH4 seems to have the layer set at both a fixed depth and level of attenuation, this app attempts to provide a more varied experience by adjusting the attenuation value by season (simulating the varying depth of the thermocline over the course of the year), as well as introducing a degree of randomness to the effect (thereby accounting in some measure for the broad spectrum of possible conditions that affect detection probabilities for contacts across the layer).
download link ==>
http://rapidshare.com/files/24230822/Thermalizer.rar.html