Publication

Journal	Environmental Research Letters
Volume (Issue)	16(4)
Page(s)	044037 - 044037
Title of proceedings	Environmental Research Letters
DOI	10.1088/1748-9326/abe74a

Remote research stations are guarantor of high-quality atmospheric measurements as they areessentially exposed to pristine air masses. However, in a context of increasing touristic pressure forcertain sites, attention should be paid to the local anthropogenic emission related to theinfrastructure itself. Among emissions, carbon dioxide (CO2) is the most important anthropogenicgreenhouse gas and a major contributor to the current global warming. Here, we comparedtwo years of CO2dry air mole fraction records from Jungfraujoch (Swiss Alps) measured at theSphinx Laboratory (3580 m a.s.l.; JFJ) and the East Ridge facility (3705 m a.s.l.; JER; horizontaldistance of∼1 km), respectively. Both stations show an overall increase of the annual mean CO2mole fraction in line with current global trends. On a daily basis, values during the night(00h00–06h00) show robust coherence with variability ranging within the measurement uncertainties matching the WMO compatibility goal of 0.1 ppm, which we considered to be background air CO2mole fraction for Central and Western Europe. However, JFJ record shows superimposed short-term variability with diurnal CO2spikes centered around noon. Whereas the variability occurring during time intervals ranging from days to weeks seem to be driven by inputs of air masses from the planetary boundary layer, we suppose that the super-imposed diurnal CO2spikes occurring essentially in summer are explained by local emission sources related to the infrastructure (visitors, tourism, etc). Nevertheless, we cannot point to a single triggering cause for those spikes as it probably results from a combination of factors. In order to minimize these local emissions, smooth collaboration between all the involved stakeholders is required.