Changes in bioclimatic conditions on the coast of the Labrador Peninsula from the end of the 19th century to the mid-20th century, compared to the contemporary period

The contemporary warming currently being observed on Earth is most intense in the Arctic and Sub-Arctic. Until the mid-20th century, human impact on the Arctic environment and climate was small, so it is extremely important to maximally understand these past conditions in order to better understand current and future changes.

To date, there has been little work based on climate data from Labrador dating back to the 19th century. In the case of bioclimatic studies, even fewer such works exist. In order to fill this gap, the following analyses were performed.

Changes in bioclimatic conditions in the north-eastern Labrador Peninsula were estimated based on two series of measurements. The first includes six years of meteorological observations from six measurement stations: Hebron, Hoffenthal, Nain, Okak Rama, and Zoar. The second series is based on data from the Hebron and Nain stations and covers nearly 50 years of data. Moravian missionaries conducted the meteorological measurements on behalf of the Deutsche Seewarte (German Society for the Protection of Climate). Contemporary data for comparison were obtained from the Canadian Centre for Climate Services and cover the years 1991–2020.

Deutsche Seewarte Hamburg provided the stations with tested and calibrated measuring instruments. Meteorological observations were carried out in accordance with the standardised Seewarte guidelines. These data were digitalised and made available by Deutscher Wetterdienst (DWD).

During the observations, measurements were taken of, among others, air temperature, atmospheric pressure and wind speed and direction. They were taken daily at three measurement times: 8:00, 14:00 and 20:00. Based on these data, bioclimatic analyses of selected bioclimatic indices were performed: Wind Chill Temperature (WCT) and Insulation Predicted (Iclp).

The data presented included the monthly mean values ​​of selected parameters and their year-to-year changes. The frequencies of individual categories of meteorological conditions were determined based on the analysed bioclimatic indices. The results were compared with values ​​obtained at other stations and compared to the conditions currently prevailing on the peninsula.

Based on the analyses conducted, it appears that, during the historical period, the average annual air temperature was lower, but wind speeds were also lower. Differences in bioclimatic conditions between the stadia are small, but conditions are least favourable in the north of the peninsula, whereas they are most favourable in the south.

 

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