Long-term reliability of the Figaro TGS 2600 solid-state methane sensor under low-Arctic conditions at Toolik Lake, Alaska
The TGS 2600 was the first low-cost solid-state sensor that shows a response to ambient levels of CH 4 (e.g., range ≈1.8 –2.7 µmol mol −1 ). Here we present an empirical function to correct the TGS 2600 signal for temperature and (absolute) humidity effects and address the long-term reliability of t...
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ftcopernicus:oai:publications.copernicus.org:amt81270 2023-05-15T15:19:35+02:00 Long-term reliability of the Figaro TGS 2600 solid-state methane sensor under low-Arctic conditions at Toolik Lake, Alaska Eugster, Werner Laundre, James Eugster, Jon Kling, George W. 2020-05-27 application/pdf https://doi.org/10.5194/amt-13-2681-2020 https://amt.copernicus.org/articles/13/2681/2020/ eng eng doi:10.5194/amt-13-2681-2020 https://amt.copernicus.org/articles/13/2681/2020/ eISSN: 1867-8548 Text 2020 ftcopernicus https://doi.org/10.5194/amt-13-2681-2020 2020-07-20T16:22:09Z The TGS 2600 was the first low-cost solid-state sensor that shows a response to ambient levels of CH 4 (e.g., range ≈1.8 –2.7 µmol mol −1 ). Here we present an empirical function to correct the TGS 2600 signal for temperature and (absolute) humidity effects and address the long-term reliability of two identical sensors deployed from 2012 to 2018. We assess the performance of the sensors at 30 min resolution and aggregated to weekly medians. Over the entire period the agreement between TGS-derived and reference CH 4 mole fractions measured by a high-precision Los Gatos Research instrument was R 2 =0.42 , with better results during summer ( R 2 =0.65 in summer 2012). Using absolute instead of relative humidity for the correction of the TGS 2600 sensor signals reduced the typical deviation from the reference to less than ±0.1 µmol mol −1 over the full range of temperatures from −41 to 27 ∘ C . At weekly resolution the two sensors showed a downward drift of signal voltages indicating that after 10–13 years a TGS 2600 may have reached its end of life. While the true trend in CH 4 mole fractions measured by the high-quality reference instrument was 10.1 <math xmlns="http://www.w3.org/1998/Math/MathML" id="M13" display="inline" overflow="scroll" dspmath="mathml"><mrow class="unit"><mi mathvariant="normal">nmol</mi><mspace linebreak="nobreak" width="0.125em"/><msup><mi mathvariant="normal">mol</mi><mrow><mo>-</mo><mn mathvariant="normal">1</mn></mrow></msup><mspace linebreak="nobreak" width="0.125em"/><msup><mi mathvariant="normal">yr</mi><mrow><mo>-</mo><mn mathvariant="normal">1</mn></mrow></msup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="76pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="73ee9520c8d75acdb95d28bc5e4da24c"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-13-2681-2020-ie00001.svg" width="76pt" height="15pt" src="amt-13-2681-2020-ie00001.png"/></svg:svg> (2012–2018), part of the downward trend in sensor signal (ca. 40 %–60 %) may be due to the increase in CH 4 mole fraction because the sensor voltage decreases with increasing CH 4 mole fraction. Weekly median diel cycles tend to agree surprisingly well between the TGS 2600 and reference measurements during the snow-free season, but in winter the agreement is lower. We suggest developing separate functions for deducing CH 4 mole fractions from TGS 2600 measurements under cold and warm conditions. We conclude that the TGS 2600 sensor can provide data of research-grade quality if it is adequately calibrated and placed in a suitable environment where cross-sensitivities to gases other than CH 4 are of no concern. Text Arctic Alaska Copernicus Publications: E-Journals Arctic Atmospheric Measurement Techniques 13 5 2681 2695 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
The TGS 2600 was the first low-cost solid-state sensor that shows a response to ambient levels of CH 4 (e.g., range ≈1.8 –2.7 µmol mol −1 ). Here we present an empirical function to correct the TGS 2600 signal for temperature and (absolute) humidity effects and address the long-term reliability of two identical sensors deployed from 2012 to 2018. We assess the performance of the sensors at 30 min resolution and aggregated to weekly medians. Over the entire period the agreement between TGS-derived and reference CH 4 mole fractions measured by a high-precision Los Gatos Research instrument was R 2 =0.42 , with better results during summer ( R 2 =0.65 in summer 2012). Using absolute instead of relative humidity for the correction of the TGS 2600 sensor signals reduced the typical deviation from the reference to less than ±0.1 µmol mol −1 over the full range of temperatures from −41 to 27 ∘ C . At weekly resolution the two sensors showed a downward drift of signal voltages indicating that after 10–13 years a TGS 2600 may have reached its end of life. While the true trend in CH 4 mole fractions measured by the high-quality reference instrument was 10.1 <math xmlns="http://www.w3.org/1998/Math/MathML" id="M13" display="inline" overflow="scroll" dspmath="mathml"><mrow class="unit"><mi mathvariant="normal">nmol</mi><mspace linebreak="nobreak" width="0.125em"/><msup><mi mathvariant="normal">mol</mi><mrow><mo>-</mo><mn mathvariant="normal">1</mn></mrow></msup><mspace linebreak="nobreak" width="0.125em"/><msup><mi mathvariant="normal">yr</mi><mrow><mo>-</mo><mn mathvariant="normal">1</mn></mrow></msup></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="76pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="73ee9520c8d75acdb95d28bc5e4da24c"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="amt-13-2681-2020-ie00001.svg" width="76pt" height="15pt" src="amt-13-2681-2020-ie00001.png"/></svg:svg> (2012–2018), part of the downward trend in sensor signal (ca. 40 %–60 %) may be due to the increase in CH 4 mole fraction because the sensor voltage decreases with increasing CH 4 mole fraction. Weekly median diel cycles tend to agree surprisingly well between the TGS 2600 and reference measurements during the snow-free season, but in winter the agreement is lower. We suggest developing separate functions for deducing CH 4 mole fractions from TGS 2600 measurements under cold and warm conditions. We conclude that the TGS 2600 sensor can provide data of research-grade quality if it is adequately calibrated and placed in a suitable environment where cross-sensitivities to gases other than CH 4 are of no concern. |
format |
Text |
author |
Eugster, Werner Laundre, James Eugster, Jon Kling, George W. |
spellingShingle |
Eugster, Werner Laundre, James Eugster, Jon Kling, George W. Long-term reliability of the Figaro TGS 2600 solid-state methane sensor under low-Arctic conditions at Toolik Lake, Alaska |
author_facet |
Eugster, Werner Laundre, James Eugster, Jon Kling, George W. |
author_sort |
Eugster, Werner |
title |
Long-term reliability of the Figaro TGS 2600 solid-state methane sensor under low-Arctic conditions at Toolik Lake, Alaska |
title_short |
Long-term reliability of the Figaro TGS 2600 solid-state methane sensor under low-Arctic conditions at Toolik Lake, Alaska |
title_full |
Long-term reliability of the Figaro TGS 2600 solid-state methane sensor under low-Arctic conditions at Toolik Lake, Alaska |
title_fullStr |
Long-term reliability of the Figaro TGS 2600 solid-state methane sensor under low-Arctic conditions at Toolik Lake, Alaska |
title_full_unstemmed |
Long-term reliability of the Figaro TGS 2600 solid-state methane sensor under low-Arctic conditions at Toolik Lake, Alaska |
title_sort |
long-term reliability of the figaro tgs 2600 solid-state methane sensor under low-arctic conditions at toolik lake, alaska |
publishDate |
2020 |
url |
https://doi.org/10.5194/amt-13-2681-2020 https://amt.copernicus.org/articles/13/2681/2020/ |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Alaska |
genre_facet |
Arctic Alaska |
op_source |
eISSN: 1867-8548 |
op_relation |
doi:10.5194/amt-13-2681-2020 https://amt.copernicus.org/articles/13/2681/2020/ |
op_doi |
https://doi.org/10.5194/amt-13-2681-2020 |
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Atmospheric Measurement Techniques |
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13 |
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5 |
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2681 |
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2695 |
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1766349782984425472 |