http://bolin.su.se/data/tarfala-kirchner-2023-lake-temperature-1 Nina Kirchner, Joachim Jansen Bolin Centre Database 2023 Datafile Lacustrine Hydrology Cryostratification Observations Lake Tarfala Tarfala Lake ice Water temperatures Under-ice Lake ice phenology Earth science > Cryosphere > Snow/ice > Lake ice Nina Kirchner 2023-12-05T12:35:15+00:00 English 1 Data were acquired in the central part of Lake Tarfala, located at 67° 55’ 28’’ N, 18° 35’ 22’’ E and an elevation of 1162 m above sea level, using instruments anchored to a mooring line. The instruments logged, time-stamped (UTC+2) and saved the water temperature every 30 minutes during 2019-2020 and every 15 minutes during 2021-2022. An exception is the pressure sensor (also recording water temperature) which acquired measurements every 30 minutes starting in 2021. ##### Data are provided in csv-files 1. `WaterTemp2019-2020.csv` contains 17929 date- and timestamped water temperature measurements at 38 m, 28 m, 18 m, 8 m, 4 m and 2 m water depths. Data is from HOBO Water Temp Pro v2 profilers and Seabird Scientific SBE56 temperature sensors (for details, see Reference provided) with the following columns: 1. `Date (YYYY-MM-DD)`: Date in the format year-month-day 1. `Time (HH:MM:SS)`: Time in the format hours-minutes-seconds 1. `38 m`: water temperatures at 38 m water depth 1. `28 m`: water temperatures at 28 m water depth 1. `18 m`: water temperatures at 18 m water depth 1. `8 m`: water temperatures at 8 m water depth 1. `4 m`: water temperatures at 4 m water depth 1. `2 m`: water temperatures at 2 m water depth 1. `WaterTemp2021-2022.csv` contains 32159 date- and timestamped water temperature measurements (degrees Celsius) at 40 m, 30 m, 20 m, 10 m, 4 m, 3 m and 2 m water depths. The pressure sensor (at 3 m water depth) renders also water temperature, but only every 30 minutes (see above). Time instances for which no data is available from 3 m water depth is indicated by NaN. Data is from HOBO U22 Water Temp Pro v2 profilers and Seabird Scientific SBE56 temperature sensors (for details, see Reference provided) with the following columns: 1. `Date (YYYY-MM-DD)`: Date in the format year-month-day 1. `Time (HH:MM:SS)`: Time in the format hours-minutes-seconds 1. `40 m`: water temperatures at 40 m water depth 1. `30 m`: water temperatures at 30 m water depth 1. `20 m`: water temperatures at 20 m water depth 1. `10m`: water temperatures at 10 m water depth 1. `4 m`: water temperatures at 4 m water depth 1. `3 m`: water temperatures at 3 m water depth 1. `2 m`: water temperatures at 2 m water depth 1. `WaterPressure2021-2022.csv` contains 16080 date- and timestamped water pressure measurements (in kPa = kilopascal) at 3 m water depth. Data is from a HOBO U22 Water Level Logger (for details, see Reference provided) with the following columns: 1. `Date (YYYY-MM-DD)`: Date in the format year-month-day 1. `Time (HH:MM:SS)`: Time in the format hours-minutes-seconds 1. `Pressure (kPa)`: water pressures at 3 m water depth ##### Photography `dji_fly_20230724_121706_821_1690194707773_photo.jpg` photo of Lake Tarfala by Florian Vacek. ##### Note When the mooring was retrieved on September 14, 2020, it had collapsed and was retrieved with all sensors and the mooring line bundled together, and with lake sediments on the mooring line. We believe that the mooring collapsed in July 2020, during the ice-off process. Indirect evidence are the very similar water temperatures at all depths after July 25, 2020, which we chose to not remove from the dataset since we do not have any direct proof for a collapse of the mooring. The support of our co-workers on the Arctic Avenue activity Lake thermal and mixing dynamics under changing climate (J. Weckström, K. Weckström, A. Korhola, F. Schenk, A. Granebeck) is gratefully acknowledged. Tarfala Research Station staff, especially Torgny Lundberg and Martin Houssais, are thanked for support in the field. The dataset is a continuation of earlier measurements, see [tarfala-kirchner-2020-lake-temperature-1](https://bolin.su.se/data/tarfala-kirchner-2020-lake-temperature-1).