Liquid-in-glass thermometer calibration service

Wise, Jacquelyn A.

doi:10.6028/nist.sp.250-23

Cited by 15 publications

(15 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this case the system is routinely validated in an ice-bath allowing correction for any calibration drift. The accuracy of an ice-bath is ~± 0.01 °C 50 . Using the offset determined during this validation to correct the data greatly increases the measurement accuracy near 0 °C, an important reference point for permafrost.…”

Section: Methodsmentioning

confidence: 99%

Permafrost is warming at a global scale

Biskaborn

Smith

Nötzli³

et al. 2019

Nat Commun

1,273

772

View full text Add to dashboard Cite

Permafrost warming has the potential to amplify global climate change, because when frozen sediments thaw it unlocks soil organic carbon. Yet to date, no globally consistent assessment of permafrost temperature change has been compiled. Here we use a global data set of permafrost temperature time series from the Global Terrestrial Network for Permafrost to evaluate temperature change across permafrost regions for the period since the International Polar Year (2007–2009). During the reference decade between 2007 and 2016, ground temperature near the depth of zero annual amplitude in the continuous permafrost zone increased by 0.39 ± 0.15 °C. Over the same period, discontinuous permafrost warmed by 0.20 ± 0.10 °C. Permafrost in mountains warmed by 0.19 ± 0.05 °C and in Antarctica by 0.37 ± 0.10 °C. Globally, permafrost temperature increased by 0.29 ± 0.12 °C. The observed trend follows the Arctic amplification of air temperature increase in the Northern Hemisphere. In the discontinuous zone, however, ground warming occurred due to increased snow thickness while air temperature remained statistically unchanged.

show abstract

Section: Methodsmentioning

confidence: 99%

Permafrost is warming at a global scale

Biskaborn

Smith

Nötzli³

et al. 2019

Nat Commun

1,273

772

View full text Add to dashboard Cite

show abstract

“…A single-point (or offset) calibration in a stirred ice-water bath at 0 • C constitutes the most suitable calibration method. A precise reference thermometer should be used to check that the ice bath is properly mixed and at 0 • C ± 0.01 • C during the entire procedure (Wise, 1988). The entire sensor chain has to be well covered within the ice-water bath and must not touch any walls of the container.…”

Section: Calibration Proceduresmentioning

confidence: 99%

Best Practice for Measuring Permafrost Temperature in Boreholes Based on the Experience in the Swiss Alps

Nötzli¹,

Arenson

Bast³

et al. 2021

Front. Earth Sci.

View full text Add to dashboard Cite

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.

show abstract

“…Prior to the measurement of the eighteen LiG thermometers, the thermometers were visually inspected for acceptance using a 10× microscope to check for defects, which may include foreign material in the capillary, improperly numbered graduations, or non-uniform markings [3].…”

Section: Measurement Of Test Lig Thermometersmentioning

confidence: 99%

“…The second ice MP value is measured after a 72 h rest period following the highest measured temperature for that LiG thermometer. As described in the American Society for Testing and Materials standards E 1 and E 77, Faden or auxiliary thermometers are used for making stem temperature corrections of partial immersion thermometers for temperatures above 150 °C [3,4,5].…”

Section: Measurement Of Test Lig Thermometersmentioning

confidence: 99%

NIST Calibration Uncertainties of Liquid-in-Glass Thermometers over the Range from −20 °C to 400 °C

Vaughn¹,

Strouse²

2003

AIP Conference Proceedings

View full text Add to dashboard Cite

The National Institute of Standards and Technology (NIST) Industrial Thermometer Calibration Laboratory (ITCL) is responsible for calibrating several different types of industrial thermometers. One of those types is the liquidin-glass (LiG) thermometer, which includes both mercury (partial and total immersion) and organic (total immersion) filled models. Over the past two years, improvements in both calibration equipment and software used in the ITCL has led to a new assessment of the uncertainties assigned to the calibration of LiG thermometers covering the temperature range from -20 °C to 400 °C. In total, eighteen thermometers from three different manufacturers, six of which are mercury-filled partial immersion, twelve of which are mercury-filled total immersion, and two of which are organicfilled total immersion models, were used for the determination of LiG thermometer calibration uncertainties over the range from −20 °C to 400 °C in the NIST ITCL.

show abstract

Liquid-in-glass thermometer calibration service

Cited by 15 publications

References 0 publications

Permafrost is warming at a global scale

Permafrost is warming at a global scale

Best Practice for Measuring Permafrost Temperature in Boreholes Based on the Experience in the Swiss Alps

NIST Calibration Uncertainties of Liquid-in-Glass Thermometers over the Range from −20 °C to 400 °C

Contact Info

Product

Resources

About