Bioclimatic conditions in the north-eastern part of the Labrador Peninsula in the second half of the 18th century

The bioclimate of the north-eastern part of the Labrador Peninsula was estimated based on meteorological observations from three measuring stations: Nain, Okak and Hopedale. The meteorological measurements were taken by Moravian Missionaries who conducted religious missions in this area.

The collected data concerned air temperature, atmospheric pressure and wind speed and direction. Observations were carried out four times a day, at 8 a.m., 12 p.m., 4 p.m. and 8 p.m. The materials used in this work came from three European archives: the Moravian Archives in Herrnhut (Germany), the Moravian Archives at Muswell Hill in London, and the Archives of the Royal Society in London (Great Britain).

In order to compare bioclimatic analyses between stations, it was decided to standardise measurement periods. Two time slots were designated:

• from September 1776 to August 1786 (~98% data coverage): the analysis included data from the Nain and Okak stations at 12:00 local time, due to the bioclimatic conditions being most favourable for humans at that time,
• from September 1782 to August 1786, with an annual gap from September 1784 to August 1785 (~93% data coverage): three measuring stations were analysed: Nain, Okak and Hopedale. The time interval was determined based on the shortest data series (i.e., that from the Hopedale station).

In order to present the bioclimatic conditions in the north-eastern part of the Labrador Peninsula, the following indicators were used: Wind Chill Temperature (WCT), Wind Chill Index (WCI) and Insulation Predicted (Iclp). The results were compared with the reference period (1991–2020) from the Nain station.

It was found that, in the first of the specified time intervals (lasting 10 years), the bioclimatic conditions were more favourable than in the comparative period. However, it is worth noting that the conditions in Nain were less bearable for humans than in Okak. In the second time period (only 3 years), the most difficult conditions prevailed at the Okak station. Milder conditions were recorded at Nain station, while the most favourable were recorded at Hopedale. This was primarily due to the analysed time period. During the measurements, relatively mild winters were recorded at the Hopedale station, which influenced the final result.

At each station during the analysis period, conditions for humans were less favourable than in the reference period. The main role in this matter was played by wind speed, which was much higher in 1991–2020 than in the second half of the 18th century.

 

The work was supported by the National Science Centre, Poland project No. 2020/39/B/ST10/00653.