Thirty Years of Atmospheric CO₂ Observations at the Plateau Rosa Station, Italy

• Main Authors: Francesco Apadula, Claudio Cassardo, Silvia Ferrarese, Daniela Heltai, Andrea Lanza
• Format: Article
• Language: English
• Published: MDPI AG 2019-07-01
• Series: Atmosphere
• Subjects: Plateau Rosa station; background CO₂ time series; BaDS filter; CO₂ growth rate; climatic variability indexes
• Online Access: https://www.mdpi.com/2073-4433/10/7/418

The atmospheric background CO₂ concentration is a key quantity for the analysis and evaluation of the ongoing climate change. Long-term CO₂ observations have been carried out at the high Plateau Rosa mountain station, in the north-western Alps since 1989. The complete time series covers thirty years, and it is suitable for climatological analysis. The continuous CO₂ measurements, collected since 1993, were selected, by means of a BaDS (Background Data Selection) filter, to obtain the hourly background data. The monthly background data series was analysed in order to individuate the parameters that characterise the seasonal cycle and the long-term trend. The growth rate was found to be 2.05 ± 0.03 ppm/year, which is in agreement with the global trend. The increased background CO₂ concentration at the Plateau Rosa site is the consequence of global anthropic emissions, whereas the natural variability of the climatic system taken from the SOI (South Oscillation Index) and MEI (Multivariate ENSO Index) signals was detected in the inter-annual changes of the Plateau Rosa growth rate.