22. Meteorology of Butler Cave

Precise measurements of temperature and relative humidity were made along a traverse from the Butler Cave entrance to Sand Canyon and along the Butler trunk channel. Summer temperatures decrease with distance into the cave but stabilize at the cave ambient only 800–1000 feet inside. Winter temperatures rise more rapidly and reach cave ambient within 100 feet. Temperature rises by a small amount along the Trunk Channel with the highest temperature at the downstream end. The temperature rise with depth along the Trunk Channel is consistent with the geothermal gradient in the area. In a separate investigation, a fan was used to introduce an oscillating air current to one cave entrance which a sensitive anemometer and data-logger used to record air flow from a difference cave entrance. The recorded square-wave pattern confirmed connections between caves over considerable distances.