Time-Lapse Records of Lake Ice Phenology from 10 Small Arctic Lakes in North-West Finnish Lapland, 2020 – ⁠2022

Field camera records, capturing the freezing (ice-on) and melting (ice-off) progression of 10 small lakes in north-west Finnish Lapland from fall 2020 to spring 2022. One trail camera (Willfine 4.0 P-CG, 100° FOV) was installed along the shore of each study lake. At low elevations (< 300 m a.s.l.), cameras were positioned at by the lakeshoreline, approx. 2 m above ground. At high elevations (> 700 m a.s.l.), cameras stood at distances of 50–150 m from the shoreline, 5–15 m above the lake. Most of each lake's surface is in frame (see overview figure). Images were recorded bi-hourly. Records of the following lakes are included: Lake Coordinates Elevation Area Max. depth Secchi depth Field records [°N, °E] [m a.s.l.] [ha] [m] [m] On 20 Off 21 On 21 Off 22 wfl5 Jänkkäjärvi 68.099, 23.394 248 4.3 3.4 2.7 x x wfl29 Etu-Vuossijärvi 68.100, 23.412 246 4.0 8.5 3.0 x x x x wfl6 Kirjoituskannonriipi 68.128, 23.355 251 1.5 4.3 ≥ 4.3 x wfl30 68.132, 23.357 251 1.3 4.0 3.1 x x x wfl11 Pikku Saarijärvi 68.398, 22.853 313 2.2 4.0 ≥ 4.0 x x x wfl12 68.442, 22.590 333 2.0 1.9 ≥ 1.9 x wfl13 68.468, 22.432 323 2.6 4.0 ≥ 4.0 x x x x wfl54 69.033, 21.120 797 9.3 8.0 7.0 x x x wfl55 Jágonajávri 69.057, 21.211 774 20.4 2.0 ≥ 2.0 x wfl56 69.173, 21.046 1011 9.6 15.0 ≥ 15.0 x x Note: Files are named after their creation date and time. Due to camera-internal time resetting, some field records' EXIF dates had to be reconstructed. The following table lists records with incorrect timestamps and their correction. Lake Season Incorrectly labeled starting date Correct starting date wfl5 Ice-off 2022 2022.05.15_06.00 2022.05.12_06.00 wfl30 Ice-off 2021 2021.05.15_10.00 2021.05.16_10.00 wfl11 Ice-off 2022 2022.05.18_04.39 2022.05.19_04.39 wfl13 Ice-off 2022 2022.05.13_20.20 2022.05.14_20.20 wfl55 Ice-on 2021 2021.09.07_09.30 2021.10.07_09.30 wfl56 Ice-off 2021 2021.05.18_14.00 2021.05.19_14.00