Harsh environments require extra thought relative to your cooling strategy. For one thing, the environmental range is significantly wider than if you are designing for an office environment or even shop floor.
Another factor that may need to be considered is weight. Will the end solution be carried by a person or robot? If so what’s their limit relative to payload themselves?
At SEMI-THERM 2009, Rockwell presented their thoughts on thermal trends in harsh environments. They were kind enough to post it to Slideshare so we might all benefit. You can reach their presentation by clicking to, “Thermal Trends in Harsh Environmental Electronics“.