Comparative study of bioclimatic conditions in southwestern Greenland between the late 18th century and the present.

The paper compares the scope and nature of changes in meteorological and biometeorological conditions in Nuuk (SW Greenland) in the second half of the 18th century for “expedition years” (Sep–Aug of: 1767–68, 1789–90, 1790–91 and 1791–92) against the contemporary period (1991–2020). The analysis used air temperature, wind speed and biometeorological indices: wind chill temperature (WCT) and insulation predicted (Iclp). The analysis was performed for individual days and months, and the comparison covers mainly the period January–June, for which complete data are available. The study showed that, in the years 1789–92, the prevailing conditions according to WCT were very similar to the contemporary period. However, according to WCT, 1768 was 4.5 °C milder for humans compared to current prevailing conditions for the period January–June. These relationships are also confirmed by the analysis of the Iclp index. Weather conditions were decidedly less burdensome for humans in 1768; for example, a person on the move needed about 0.3 clo less clothing than today. This paper is the first historical bioclimatology study of weather conditions for humans in 18th-century Greenland.