I wonder if you could conceal yourself with one of those space blankets? Anyone got a FLIR handset to test? Stealth Hoodie Hides Wearer From Drones : Discovery News
Really depends on "WHERE You are".... Up here in Alaska, during the winter, there is almost NOTHING that can hide you, with a below Zero Ambient Background. You are just way to warm..... But in the South, during the summer with a 50+F ambient Background, it a whole nother Story... ..... YMMV, or YTMV in this case....
I'm not sure an igloo would hide you up there in Alaska. Ventilation hole and doorway would still plume.