Automated ground-based remote sensing measurements of greenhouse gases at the Białystok site in comparison with collocated in situ measurements and model data

摘要

The in situ boundary layer measurement site in Białystok (Poland) has beenupgraded with a fully automated observatory for total greenhouse gas columnmeasurements. The automated Fourier Transform Spectrometer (FTS) complementsthe on-site in situ facilities and FTS solar absorption measurements havebeen recorded nearly continuously in clear and partially cloudy conditionssince March 2009. Here, the FTS measurements are compared with the collocatedtall tower data. Additionally, simulations of the Jena CO inversion modelare evaluated with the Białystok measurement facilities. The simulatedseasonal CO cycle is slightly overestimated by a mean difference of1.2 ppm ± 0.9 ppm (1σ) in comparison with the FTSmeasurements. CO concentrations at the surface, measured at the talltower (5 m, 90 m, 300 m), are slightly underestimated by −1.5 ppm,−1.6 ppm, and −0.7 ppm respectively during the day and by −9.1 ppm,−5.9 ppm, and −1.3 ppm during the night. The comparison of thesimulated CO profiles with low aircraft profiles shows a slightoverestimation of the lower troposphere (by up to 1 ppm) and anunderestimation in near-surface heights until 800 m (by up to 2.5 ppm). Inan appendix the automated FTS observatory, including the hardware componentsand the automation software, is described in its basics.