Data_Sheet_1_Best Practice for Measuring Permafrost Temperature in Boreholes Based on the Experience in the Swiss Alps.PDF

• Main Authors: Jeannette Noetzli (10779582), Lukas U. Arenson (10779585), Alexander Bast (10779588), Jan Beutel (7883948), Reynald Delaloye (10779591), Daniel Farinotti (10015952), Stephan Gruber (4740876), Hansueli Gubler (10779594), Wilfried Haeberli (7990637), Andreas Hasler (7883957), Christian Hauck (8403309), Martin Hiller (10779597), Martin Hoelzle (7550609), Christophe Lambiel (689101), Cécile Pellet (10779600), Sarah M. Springman (10779603), Daniel Vonder Muehll (10779606), Marcia Phillips (10779609)
• Format: Dataset
• Language: unknown
• Published: 2021
• Subjects: Solid Earth Sciences; Climate Science; Atmospheric Sciences not elsewhere classified; Exploration Geochemistry; Inorganic Geochemistry; Isotope Geochemistry; Organic Geochemistry; Geochemistry not elsewhere classified; Igneous and Metamorphic Petrology; Ore Deposit Petrology; Palaeontology (incl. Palynology); Structural Geology; Tectonics; Volcanology; Geology not elsewhere classified; Seismology and Seismic Exploration; Glaciology; Hydrogeology; Natural Hazards; Quaternary Environments; Earth Sciences not elsewhere classified; Evolutionary Impacts of Climate Change; permafrost; borehole temperatures; high mountain areas; long-term monitoring; best practices
• Online Access: https://doi.org/10.3389/feart.2021.607875.s001

Temperature measurements in boreholes are the most common method allowing the quantitative and direct observation of permafrost evolution in the context of climate change. Existing boreholes and monitoring networks often emerged in a scientific context targeting different objectives and with different setups. A standardized, well-planned and robust instrumentation of boreholes for long-term operation is crucial to deliver comparable, high-quality data for scientific analyses and assessments. However, only a limited number of guidelines are available, particularly for mountain regions. In this paper, we discuss challenges and devise best practice recommendations for permafrost temperature measurements at single sites as well as in a network, based on two decades of experience gained in the framework of the Swiss Permafrost Monitoring Network PERMOS. These recommendations apply to permafrost observations in mountain regions, although many aspects also apply to polar lowlands. The main recommendations are (1) to thoroughly consider criteria for site selection based on the objective of the measurements as well as on preliminary studies and available data, (2) to define the sampling strategy during planification, (3) to engage experienced drilling teams who can cope with inhomogeneous and potentially unstable subsurface material, (4) to select standardized and robust instrumentation with high accuracy temperature sensors and excellent long-term stability when calibrated at 0°C, ideally with double sensors at key depths for validation and substitution of questionable data, (5) to apply standardized maintenance procedures allowing maximum comparability and minimum data processing, (6) to implement regular data control procedures, and (7) to ensure remote data access allowing for rapid trouble shooting and timely reporting. Data gaps can be avoided by timely planning of replacement boreholes. Recommendations for standardized procedures regarding data quality documentation, processing and final publication will follow later.