Efecto en la temperatura de las visitas turísticas en la Cueva del Águila, Ávila. Valoración de la viabilidad de la cueva para el estudio térmico de su dinámica natural

Abstract

The present study focuses on the importance of visitors in Eagle Cave temperature, a tourist cavern in Ávila, central Spain. Cave air temperature was measured during a year and natural and anthropogenic thermal effects were identified. Eagle Cave has a rather stable temperature around 15.6ºC with an annual cycle which amplitude is <0.4ºC. Recorded seasonality in the cave is related to external temperatures due to thermal conduction through the bedrock, with an expected delay of several years for the external signal to be transferred into the cave. The visitors cause increases in diurnal temperature up to 0.15ºC, although thermal anomalies are normally recovered overnight. During vacation periods, where consecutive days with large number of visitors increases, thermal anomalies are prolonged for some days or weeks, with amplitudes <0.1ºC. Although visitors have a daily impact on the cave temperature, the effect does not cause long term change in Eagle Cave temperature. The reason for this thermal mitigation is related to the high humidity of the environment, which causes the energy supplied by tourists to be partially transferred as latent heat via evaporation and condensation processes. The current condensation processes are insufficient to cause any discernible condensation corrosion that could be damaging recent stalagmites