Carbon Dioxide Sources, Storage and Transport in the Cave Atmosphere

Abstract

The results of carbon dioxide (CO₂) monitoring in Srednja Bijambarska Cave (Bosnia and Herzegovina) are presented and discussed. Temporal variations of the concentration are controlled by the switching between two ventilation regimes driven by outside temperature changes. A regression model with a simple perfectly mixed volume applied to a cave sector (“Music hall”) resulted in an estimate of ventilation rates between 0.02 and 0.54 h⁻¹. Carbon dioxide input per plan surface unit is estimated by the model at around 50 × 10⁻⁶ m h⁻¹ during the winter season, to more than 1000 × 10⁻⁶ m h⁻¹ during the first temperature falls at the end of summer (0.62 and 12.40 μmol m⁻² s⁻¹ at normal conditions respectively). These values have been found to be related to the cave ventilation rate and dependent on the availability of CO₂ in the surrounding environment. For airflow close to zero the values of CO₂ input per plan surface are in the order of few 10⁻⁶ m h⁻¹. The anthropogenic contribution from cave visitors has been calculated, based on two experiments, at between 0.35 and 0.45 ${\text{L}_{\text{CO}_{2}}}$  min⁻¹ person⁻¹.

Material from this chapter has been originally published in Milanolo S, Gabrovšek F (2009) Analysis of Carbon Dioxide Variations in the Atmosphere of Srednja Bijambarska Cave, Bosnia and Herzegovina. Boundary-Layer Meteorology 131(3):479–493. doi:10.1007/s10546-009-9375-5.