Cave ventilation is influenced by variations in the CO2-dependent virtual temperature Pérez Sánchez-Cañete, Enrique Serrano Ortiz, Penélope Domingo Poveda, Francisco Kowalski, Andrew Buoyancy Carbon dioxide Caves Soil ventilation Ventilation Virtual temperature Dynamics and drivers of ventilation in caves are of growing interest for different fields of science. Accumulated CO2 in caves can be exchanged with the atmosphere, modifying the internal CO2 content, affecting stalagmite growth rates, deteriorating rupestrian paintings or creating new minerals. Current estimates of cave ventilation neglect the role of high CO2 concentrations in determining air density – approximated via the virtual temperature (Tv) –, affecting buoyancy and therefore the release or storage of CO2. Here we try to improve knowledge and understanding of cave ventilation through the use of Tv in CO2-rich air to explain buoyancy for different values of temperature (T) and CO2 content. Also, we show differences between T and Tv for 14 different experimental sites in the vadose zone, demonstrating the importance of using the correct definition of Tv to determine air buoyancy in caves. The calculation of Tv (including CO2 effects) is currently available via internet using an excel template, requiring the input of CO2 (%), air temperature (ºC) and relative humidity (%). 2012-11-16T13:51:32Z 2012-11-16T13:51:32Z 2013 info:eu-repo/semantics/article Sánchez-Cañete, Enrique P.; Serrano-Ortiz, P.; Domingo, F.; Kowalski, A. S. Cave ventilation is influenced by variations in the CO2-dependent virtual. International Journal of Speleology 42: 1-8 (2013). [http://hdl.handle.net/10481/22402] 0392-6672 1827-806X (online) doi: 10.5038/1827-806X.42.1.1 http://hdl.handle.net/10481/22402 eng info:eu-repo/grantAgreement/EC/FP7/244122 http://creativecommons.org/licenses/by-nc-nd/3.0/ info:eu-repo/semantics/openAccess Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License International Union of Speleology