Stockholm Historical Weather Observations — Observation times since 1756

Anders Moberg

This dataset provides information about the time points when weather observations were made each day (morning, noon, evening) during 1756⁠⁠ – 2018 at the old astronomical observatory in Stockholm.

The observation time points each day have changed over time. Before 1823, observation time points were often not clearly documented. Therefore, before 1823, this dataset only provides estimates of likely observation time points each day based on information available in the observation diaries or in associated publications.

All observation time points are here provided in Central European Time (i.e. UTC+01:00), although other time reporting habits were used before 1901. The observation time points in this dataset have been used to provide information needed to estimate daily mean temperatures from individual temperature observations since 1756.

Citation

Anders Moberg (2019) Stockholm Historical Weather Observations — Observation times since 1756. Dataset version 1. Bolin Centre Database. https://doi.org/10.17043/stockholm-historical-obs-times-1

References

Moberg A, Bergström H, Ruiz Krigsman J, Svanered O. 2002: Daily air temperature and pressure series for Stockholm (1756–1998). Climatic Change 53: 171–212. https://doi.org/10.1023/A:1014966724670

Erratum: Climatic Change 54: 249–250. https://doi.org/10.1023/A:1017435506001

Data description

Data are provided in a single file, available in two file formats:

1. plain text file (.txt)

2. tab-separated value file (.tsv)

The dataset provides estimated or known observation times for three observations (morning, noon, evening) each day from 1756-01-01 to 2018-12-31. The time unit always corresponds to UTC+01:00.

Further information about the data file content is found in a README text file.

Comments

For the period 1756⁠ – 1822, the documentation about exact observation times is often missing. More clear information has been provided from 1823 onwards. In addition, the convention for measuring time has changed from local solar time (before 1841), local mean time (1841⁠ – 1878), a common Swedish time (1879⁠ – 1899), to Central European Time (CET) that has been used since 1900. Considering the often missing information in the early period, Moberg et al. (2002) made an attempt to estimate the time point of all individual observations, relevant in particular for thermometer observations and barometer observations, specified in CET (i.e. UTC+01:00). This dataset is available and updated here.

A discussion of the various observation times used, with an explanation of how they were converted to CET is described in section 2.4 in Moberg et al. (2002). A monthly overview is given in Table I in the associated Erratum.

The observation site is included in the national station network managed by the Swedish Meteorological and Hydrological Institute (SMHI), with station number 98210 (manual station) and 98230 (automatic station).

Note: When an automatic weather station was installed on 1996-10-01, hourly observations started to be made. However, the observation times presented in the current dataset are, consistently, a subset representing the three daily observation times (morning, noon, evening) that have been used for calculation of daily mean temperatures and for other weather observations made at the manual station.