A mean-sea-level pressure time series for Trieste, Italy (1841–2018)

Abstract. A time series of mean-sea-level pressure was built from observations performed in Trieste from 1 January 1841 to 31 December 2018. Original historical documents provided information on the instruments and on the observation sites. Mercury barometers have been always available. Until 1877 they represented the only instruments in operation, while from 1878 onwards barograph records became available. The time series consists of mean daily values, that were computed from 24 hourly data, when possible, or otherwise adjusted to 24-hr means on the basis of climatological daily pressure cycles. The time series was homogenized on the basis of the available metadata, reducing pressure to 0° C and to mean sea level. Basic quality checks were applied, including the comparison with pressure time series from nearby stations. As a result, the data prior to 1865 turned out to be suspect. A mean-sea-level pressure trend of 0.5 ± 0.2 hPa per century was estimated for the 1865–2018 period. The data are available through PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.926896 ; Raicich and Colucci, 2021).