Some features of Trieste climate from an eighteenth century diary (1732 1749)

Weather descriptions are available from a diary written in Trieste by A. Scussa from 1732 to 1749, which allow to deduce some features of thermal conditions and precipitation regimes. Indices are defined on the basis of the subjective assessment of the degree of heat and cold provided by the writer. Monthly and annual standardized anomalies are computed, that enable to put in evidence the interannual variability of the thermal conditions and allow a comparison with Padova observed temperatures. Anomalies in physical units are also estimated. The prominent fluctuations agree with those observed in Padova, although inconsistencies remain in specific months. The Trieste precipitation regime in 1732–1749 is consistent with that of the twentieth century but the precipitation frequency seems lower. Several severe droughts are also reported. Despite the methodological limitations the reconstruction appears reliable.