The oldest meteorological data for the southwest coast of Greenland date from the second half of the 18th century. Weather observations were conducted by the Moravian Brothers, who established the first Christian mission in a settlement called Nuuk (formerly: Neu-Herrnhut, Godthaab, Godthab or Godthåb).
During their mission, the Moravian Brothers compiled two series of meteorological data: 1) Sep 1767 – Jul 1768 and 2) Sep 1784 – Jun 1792. For the first series (Neu-Herrnhut), observations were made twice a day (8:00 AM and 2:00 PM LT). Parameters such as air temperature (°F), atmospheric pressure (Paris inch and Paris line), and wind direction and force (1-6) were measured. The second series (Godthaab) consists of measurements taken three times a day (7:00 AM, 2:00 PM, and 9:00 PM LT). Air temperature (°R), atmospheric pressure (Paris inch), and wind direction and force (0-4) were measured.
Historical data were quality-checked and corrected. Air temperature was converted to degrees Celsius. Atmospheric pressure to mmHg and them to hPa. The gravity correction "Pφcorr" was then applied, and the pressure was reduced to sea level altitude "SLP" using the formulas provided in Cappelan (2009). Atmospheric pressure was also corrected to the value at 0°C. For this purpose, the Kämtz formula from Können et al. (2003). For more details, see Przybylek et al. (2013). Wind speed was converted to m∙s-1 using the Beaufort scale. For more details on the conversion, see Chmist et al. (2025). New wind speed classes were defined for each series and assigned appropriate values, see Table in wind_conversion.pdf file.
References:
Cappelen J (ed.) (2009) DMI monthly climate data collection 1768–2008, Denmark, The Faroe Islands and Greenland, Technical Report 09-05. Dan. Meteorol. Inst.
Chmist K, Araźny A, Przybylak R, Wyszyński P, Singh G (2025) Changes in bioclimatic conditions on the coast of the Labrador Peninsula in the second half of the 18th century. Climatic Change 178:46. https://doi.org/10.1007/s10584-025-03883-x
Können GP, Zaiki M, Baede APM, Mikami T, Jones PD, Tsukahara T (2003) Pre-1872 extension of the Japanese instrumental meteorological observation series back to 1819. Journal of Climate 16:118–131. https://doi.org/10.1175/1520-0442(2003)016<0118:PEOTJI>2.0.CO;2
Przybylak R, Wyszyński P, Vizi Z, Jankowska J (2013) Atmospheric pressure changes in the Arctic, from 1801 to 1920. Int. J. Climatol. 33:1730–1760. https://doi.org/10.1002/joc.3546
