Figure 1
Top panel is a schematic cross-section through Chifley Cave showing the dominant convective air-flow directions for summer (red) and winter (blue). Air-flow along major passages may reverse direction daily in response to a reversal of the cave to external temperature difference, without a time lag (<15 mins). The slower passage of air from soil to cave along small cracks and fissures in summer has a longer time lag of 1–6 hrs between cave - external temperature reversal and the soil air peak in Lower Katies Bower (low CH4, high CO2, high N2O, high Rn). Lower panel is a scale diagram of continuous flow air sampling locations relative to the CRDS & FTIR instruments.
