Claudio Stefanini

The recovery of measurements from the early instrumental period is crucial for improving the quality of historical climate reconstructions, enhancing model calibration, and increasing the reliability of long-term predictions. The study aims to recover, correct, and analyze the daily pressure observations made in Bologna by Jacopo Bartolomeo Beccari and his pupils from 1715 to 1774. The empirical quantile mapping at monthly level using the Padua series as a reference resulted in the most reasonable correction method. The quality of the reconstruction was assessed through a posteriori data analysis at monthly, seasonal, and annual time scales. The reconstructed Bologna series shows general agreement with the contemporary Padua series, in particular in the day-by-day variability and percentile distribution. Moreover, its main features reflect those of the 1961–1990 reference period. The annual cycle is also consistent with the Milan and Venice series for the overlapping periods. The notable difference between the 18th-century pressure observations in Northern Italy and the paleo-reanalysis dataset ModE-RA (Modern Era Reanalysis) is likely due to the fact that instrumental measurements are only assimilated from the 18th century onward. The paper provides a new 18th-century daily dataset and is part of a broader effort aimed at reconstructing the Bologna pressure series up to the present day.

In this study, surface mass balance (SMB) is estimated from snow accumulation data collected in the nearby area of Concordia Station, Antarctica. Results from the Italian and French stake farms are jointly analysed. The Italian stake farm consists of 13 stakes; continuous observations started at the end of 2010 with near-monthly sampling. Some measurements are also available for the 2006–2010 period from a previous stake farm. The French stake farm consists of 50 stakes; observations started in 2004 with yearly sampling during austral summer. Snow buildup measurements at individual stakes show a strong variability caused by the interaction of wind-driven snow with surface micro-relief. In the common observation period, the present Italian stake farm generally underestimates the SMB with respect to the French one, except for 3 years in which an overestimation is observed. Over the 2011–2023 period, the mean yearly accumulation recorded by the Italian and French stake farms is 7.3 ± 0.2 cm and 8.4 ± 0.1 cm, respectively. Bootstrap simulation has been performed to: (i) assess the significance of the differences between the two datasets; (ii) evaluate the effect on the measurements of the different size of the stake farms and their distance to the Station. The comparison of the observations with reanalysis datasets (ERA5 and MERRA2) and regional models (RACMO2.4p1, MAR3.12) indicates the former more in agreement with the observations. The potential interaction effect of the Station has also been investigated by analysing wind direction during snowfall events, suggesting that buildings may influence accumulation. In fact, in the hyper-arid environment of Dome C, snow accumulation is largely governed by post-depositional processes such as wind redistribution and clear-sky precipitation. Buildings alter the wind field, enhancing erosion beneath them and forming snowdrifts leeward and laterally, which may explain accumulation differences between the ITA and FRA stake fields. Additionally, two more stake farms, located 25 km North and South of Concordia Station, are also analysed to study the SMB gradient across Dome C, confirming previous results. On average, yearly SMB increases northward by 8 %–9 % over the 50 km span between the southern and northern stake farms. At Concordia, for the 2004–2023 period, a mean SMB of 27.21 ± 0.60 kg m⁻² has been estimated, taking into account the uncertainty of the observations and of the snow compaction effect. Results are valuable for validating SMB estimated from reanalysis, regional climate models and remote-sensing data.

Understanding long-term cloud cover variability is essential for assessing past climate dynamics and human influences on atmospheric conditions. In Padua, instrumental weather records (temperature, precipitation, pressure) and descriptive sky observations date back to 1725, but quantitative cloud cover data, expressed as tenths of the sky covered by clouds, began in 1872 at the Astronomical Observatory. From 1920 to 1989, observations continued under the authority of the Meteorological Observatory of the Water Magistrate, and from 1951 to 1990, additional records by the Italian Air Force expressed in eighths of sky are available. These visual datasets—based on multiple daily observations—are complemented by satellite records (from 1983) and reanalysis such as ERA5 (from 1940) and NOAA 20CRv3 (from 1872 to 2015). The aim of this study is to reconstruct a homogenized, long-term total cloud cover (TCC) time series for Padua from 1872 to 2024, integrating all available observational sources. By comparing overlapping periods across different subseries and nearby ground-based stations, the analysis not only investigates consistency and potential discontinuities across datasets but also quantifies the reliability and limitations of historical visual observations. This work provides one of the few centennial-scale reconstructions of cloud cover in Europe, offering a valuable contribution to historical climatology and climate change studies.

The fog in Padua, Italy, is the result of a complex interplay between local climate, pollution and synoptic-scale meteorological conditions. The modern definition of “fog” was adopted by the World Meteorological Organization, founded in 1950. Prior to that, no precise visibility threshold had been established, and early meteorological observers recorded its occurrence based on subjective criteria. The meteorological observations made in Padua since the mid-18th century include sky conditions and fog, but the distinction between fog and mist was undefined, making it difficult to compare records from different observers. Caution is therefore needed when analyzing fog occurrence to distinguish the climate signal from observational artifacts. For instance, at the Specola Observatory in Padua from 1773 to 1913, the fog that appeared only on the horizon—but not at the zenith—was often disregarded, since vertical visibility was crucial for astronomical observations. Starting from 1920, other manned stations began providing systematic fog records, which have continued to the present. The aim of this study is to reconstruct the occurrence of fog in Padua since the late 18th century. As available datasets —observational and instrumental—partly overlap in time, and data from nearby locations are available, it is possible to assess their mutual consistency, to evaluate the reliability of historical visual observations, and to investigate fog variability and trend over time.

In this study, surface mass balance (SMB) is estimated from snow accumulation data collected in the nearby area of Concordia Station, Antarctica. Results from the Italian and French stake farms are jointly analysed. The Italian stake farm is located ~800 m southwest of Concordia Station and consists of 13 stakes; continuous observations started at the end of 2010 with near-monthly sampling. Some measurements are also available for the 2006–2010 period from a previous stake farm which was located ~500 m south-southwest of the Station, i.e., ~300 m east of the current site. The French stake farm is located ~2 km south of the base and consists of 50 stakes; observations started in 2004 with yearly sampling during austral summer. Snow build-up measurements at individual stakes show a strong variability caused by the interaction of wind-driven snow with surface micro-relief. In the common observation period, the present Italian stake farm generally underestimates the SMB with respect to the French one, except for three years in which an overestimation is observed. Over the 2011–2023 period, the mean yearly accumulation recorded by the Italian and French stake farms is 7.3±0.2 cm and 8.4±0.1 cm, respectively. Bootstrap simulation has been performed to: (i) assess the significance of the differences between the two datasets; (ii) evaluate the effect on the measurements of the different size of the stake farms and their distance to the Station. The comparison of the observations with reanalysis datasets (ERA5 and MERRA2) and regional models (RACMO2.4p1, MAR3.12) indicates the former more in agreement with the observations. The potential interaction effect of the Station has also been investigated by analysing wind direction during snowfall events, suggesting that buildings may influence accumulation when they are upwind with respect to the stake farms. Additionally, two more stake farms, located 25 km north and south of Concordia Station, are also analysed to study the SMB gradient across Dome C, confirming previous results. On average, yearly SMB increases northward by 8–9 % over the 50 km span between the southern and northern stake farms. At Concordia, for the 2004–2023 period, a mean SMB of 27.21±0.60 kg m^–2 has been estimated, taking into account the uncertainty of the observations and of the snow compaction effect. Results are valuable for validating SMB estimated from reanalysis, regional climate models and remote-sensing data.

In this study, surface mass balance (SMB) is estimated from snow accumulation data collected in the nearby area of Concordia Station, Antarctica. Results from the Italian and French stake farms are jointly analysed. The Italian stake farm is located ~800 m southwest of Concordia Station and consists of 13 stakes; continuous observations started at the end of 2010 with near-monthly sampling. Some measurements are also available for the 2006–2010 period from a previous stake farm which was located ~500 m south-southwest of the Station, i.e., ~300 m east of the current site. The French stake farm is located ~2 km south of the base and consists of 50 stakes; observations started in 2004 with yearly sampling during austral summer. Snow build-up measurements at individual stakes show a strong variability caused by the interaction of wind-driven snow with surface micro-relief. In the common observation period, the present Italian stake farm generally underestimates the SMB with respect to the French one, except for three years in which an overestimation is observed. Over the 2011–2023 period, the mean yearly accumulation recorded by the Italian and French stake farms is 7.3±0.2 cm and 8.4±0.1 cm, respectively. Bootstrap simulation has been performed to: (i) assess the significance of the differences between the two datasets; (ii) evaluate the effect on the measurements of the different size of the stake farms and their distance to the Station. The comparison of the observations with reanalysis datasets (ERA5 and MERRA2) and regional models (RACMO2.4p1, MAR3.12) indicates the former more in agreement with the observations. The potential interaction effect of the Station has also been investigated by analysing wind direction during snowfall events, suggesting that buildings may influence accumulation when they are upwind with respect to the stake farms. Additionally, two more stake farms, located 25 km north and south of Concordia Station, are also analysed to study the SMB gradient across Dome C, confirming previous results. On average, yearly SMB increases northward by 8–9 % over the 50 km span between the southern and northern stake farms. At Concordia, for the 2004–2023 period, a mean SMB of 27.21±0.60 kg m^–2 has been estimated, taking into account the uncertainty of the observations and of the snow compaction effect. Results are valuable for validating SMB estimated from reanalysis, regional climate models and remote-sensing data.

In this study, surface mass balance (SMB) is estimated from snow accumulation data collected in the nearby area of Concordia Station, Antarctica. Results from the Italian and French stake farms are jointly analysed. The Italian stake farm is located ~800 m southwest of Concordia Station and consists of 13 stakes; continuous observations started at the end of 2010 with near-monthly sampling. Some measurements are also available for the 2006–2010 period from a previous stake farm which was located ~500 m south-southwest of the Station, i.e., ~300 m east of the current site. The French stake farm is located ~2 km south of the base and consists of 50 stakes; observations started in 2004 with yearly sampling during austral summer. Snow build-up measurements at individual stakes show a strong variability caused by the interaction of wind-driven snow with surface micro-relief. In the common observation period, the present Italian stake farm generally underestimates the SMB with respect to the French one, except for three years in which an overestimation is observed. Over the 2011–2023 period, the mean yearly accumulation recorded by the Italian and French stake farms is 7.3±0.2 cm and 8.4±0.1 cm, respectively. Bootstrap simulation has been performed to: (i) assess the significance of the differences between the two datasets; (ii) evaluate the effect on the measurements of the different size of the stake farms and their distance to the Station. The comparison of the observations with reanalysis datasets (ERA5 and MERRA2) and regional models (RACMO2.4p1, MAR3.12) indicates the former more in agreement with the observations. The potential interaction effect of the Station has also been investigated by analysing wind direction during snowfall events, suggesting that buildings may influence accumulation when they are upwind with respect to the stake farms. Additionally, two more stake farms, located 25 km north and south of Concordia Station, are also analysed to study the SMB gradient across Dome C, confirming previous results. On average, yearly SMB increases northward by 8–9 % over the 50 km span between the southern and northern stake farms. At Concordia, for the 2004–2023 period, a mean SMB of 27.21±0.60 kg m^–2 has been estimated, taking into account the uncertainty of the observations and of the snow compaction effect. Results are valuable for validating SMB estimated from reanalysis, regional climate models and remote-sensing data.

In this study, surface mass balance (SMB) is estimated from snow accumulation data collected in the nearby area of Concordia Station, Antarctica. Results from the Italian and French stake farms are jointly analysed. The Italian stake farm is located ~800 m southwest of Concordia Station and consists of 13 stakes; continuous observations started at the end of 2010 with near-monthly sampling. Some measurements are also available for the 2006–2010 period from a previous stake farm which was located ~500 m south-southwest of the Station, i.e., ~300 m east of the current site. The French stake farm is located ~2 km south of the base and consists of 50 stakes; observations started in 2004 with yearly sampling during austral summer. Snow build-up measurements at individual stakes show a strong variability caused by the interaction of wind-driven snow with surface micro-relief. In the common observation period, the present Italian stake farm generally underestimates the SMB with respect to the French one, except for three years in which an overestimation is observed. Over the 2011–2023 period, the mean yearly accumulation recorded by the Italian and French stake farms is 7.3±0.2 cm and 8.4±0.1 cm, respectively. Bootstrap simulation has been performed to: (i) assess the significance of the differences between the two datasets; (ii) evaluate the effect on the measurements of the different size of the stake farms and their distance to the Station. The comparison of the observations with reanalysis datasets (ERA5 and MERRA2) and regional models (RACMO2.4p1, MAR3.12) indicates the former more in agreement with the observations. The potential interaction effect of the Station has also been investigated by analysing wind direction during snowfall events, suggesting that buildings may influence accumulation when they are upwind with respect to the stake farms. Additionally, two more stake farms, located 25 km north and south of Concordia Station, are also analysed to study the SMB gradient across Dome C, confirming previous results. On average, yearly SMB increases northward by 8–9 % over the 50 km span between the southern and northern stake farms. At Concordia, for the 2004–2023 period, a mean SMB of 27.21±0.60 kg m^–2 has been estimated, taking into account the uncertainty of the observations and of the snow compaction effect. Results are valuable for validating SMB estimated from reanalysis, regional climate models and remote-sensing data.

In this study, surface mass balance (SMB) is estimated from snow accumulation data collected in the nearby area of Concordia Station, Antarctica. Results from the Italian and French stake farms are jointly analysed. The Italian stake farm is located ~800 m southwest of Concordia Station and consists of 13 stakes; continuous observations started at the end of 2010 with near-monthly sampling. Some measurements are also available for the 2006–2010 period from a previous stake farm which was located ~500 m south-southwest of the Station, i.e., ~300 m east of the current site. The French stake farm is located ~2 km south of the base and consists of 50 stakes; observations started in 2004 with yearly sampling during austral summer. Snow build-up measurements at individual stakes show a strong variability caused by the interaction of wind-driven snow with surface micro-relief. In the common observation period, the present Italian stake farm generally underestimates the SMB with respect to the French one, except for three years in which an overestimation is observed. Over the 2011–2023 period, the mean yearly accumulation recorded by the Italian and French stake farms is 7.3±0.2 cm and 8.4±0.1 cm, respectively. Bootstrap simulation has been performed to: (i) assess the significance of the differences between the two datasets; (ii) evaluate the effect on the measurements of the different size of the stake farms and their distance to the Station. The comparison of the observations with reanalysis datasets (ERA5 and MERRA2) and regional models (RACMO2.4p1, MAR3.12) indicates the former more in agreement with the observations. The potential interaction effect of the Station has also been investigated by analysing wind direction during snowfall events, suggesting that buildings may influence accumulation when they are upwind with respect to the stake farms. Additionally, two more stake farms, located 25 km north and south of Concordia Station, are also analysed to study the SMB gradient across Dome C, confirming previous results. On average, yearly SMB increases northward by 8–9 % over the 50 km span between the southern and northern stake farms. At Concordia, for the 2004–2023 period, a mean SMB of 27.21±0.60 kg m^–2 has been estimated, taking into account the uncertainty of the observations and of the snow compaction effect. Results are valuable for validating SMB estimated from reanalysis, regional climate models and remote-sensing data.

In this study, surface mass balance (SMB) is estimated from snow accumulation data collected in the nearby area of Concordia Station, Antarctica. Results from the Italian and French stake farms are jointly analysed. The Italian stake farm is located ~800 m southwest of Concordia Station and consists of 13 stakes; continuous observations started at the end of 2010 with near-monthly sampling. Some measurements are also available for the 2006–2010 period from a previous stake farm which was located ~500 m south-southwest of the Station, i.e., ~300 m east of the current site. The French stake farm is located ~2 km south of the base and consists of 50 stakes; observations started in 2004 with yearly sampling during austral summer. Snow build-up measurements at individual stakes show a strong variability caused by the interaction of wind-driven snow with surface micro-relief. In the common observation period, the present Italian stake farm generally underestimates the SMB with respect to the French one, except for three years in which an overestimation is observed. Over the 2011–2023 period, the mean yearly accumulation recorded by the Italian and French stake farms is 7.3±0.2 cm and 8.4±0.1 cm, respectively. Bootstrap simulation has been performed to: (i) assess the significance of the differences between the two datasets; (ii) evaluate the effect on the measurements of the different size of the stake farms and their distance to the Station. The comparison of the observations with reanalysis datasets (ERA5 and MERRA2) and regional models (RACMO2.4p1, MAR3.12) indicates the former more in agreement with the observations. The potential interaction effect of the Station has also been investigated by analysing wind direction during snowfall events, suggesting that buildings may influence accumulation when they are upwind with respect to the stake farms. Additionally, two more stake farms, located 25 km north and south of Concordia Station, are also analysed to study the SMB gradient across Dome C, confirming previous results. On average, yearly SMB increases northward by 8–9 % over the 50 km span between the southern and northern stake farms. At Concordia, for the 2004–2023 period, a mean SMB of 27.21±0.60 kg m^–2 has been estimated, taking into account the uncertainty of the observations and of the snow compaction effect. Results are valuable for validating SMB estimated from reanalysis, regional climate models and remote-sensing data.