Stockholm Historical Weather Observations

Observed cloud amount, three times daily in various units

Cloud observations made at the old astronomical observatory have been digitized back to 1 January 1756. The data source for the period 1756-1861 is the hand-written diary of meteorogical observations made at the observatory, which is stored in the archive of the Royal Swedish Academy of Sciences for the period 1756-1858 and in the archive of the SMHI for the period 1859-1861. Data sources for the period 1862-1960 are the printed annual books, published by the SMHI or its predecessors, containing weather observations from all Swedish observing stations.

Digitizing of the individual observational data from 1756-1838 was made by staff at the SMHI in the mid-1990s. Digitizing of data from 1839-1960 was undertaken at Stockholm University in the late 1990s within the European Union FP4 project IMPROVE - Improved Understanding of Past Climatic Variability from Early Daily European Instrumental Sources. Data for 1961 onwards have been made available digitally by the SMHI.

Observations of cloud types and/or cloud amounts have been made in several different ways over time. A description of the various procedures is provided in Appendix A of Moberg et al. (2003). Those authors made an attempt to produce a homogenized record of cloud amount, but concluded that this was not possible longer back than to 1950. Digitized observations, three times per day, are available for download here. The data have been separated into several files depending on the observational procedures used.

Download data

Data used here for 2013 onwards were obtained by downloading from SMHI Öppna Data.

Reference

  • Moberg A, Alexandersson H, Bergström H, Jones PD. 2003: Were Southern Swedish summer temperatures before 1860 as warm as measured? Int. J. Climatol. 23: 1495-1521 (Sections 3-4 and Appendix A)