How representative are FLUXNET measurements of surface fluxes during temperature extremes?
In response to a warming climate, temperature extremes are changing in many regions of the world. Therefore, understanding how the fluxes of sensible heat, latent heat and net ecosystem exchange respond and contribute to these changes is important. We examined 216 sites from the open access Tier 1 F...
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ftosti:oai:osti.gov:1609579 2023-07-30T03:59:22+02:00 How representative are FLUXNET measurements of surface fluxes during temperature extremes? van der Horst, Sophie V. J. Pitman, Andrew J. De Kauwe, Martin G. Ukkola, Anna Abramowitz, Gab Isaac, Peter 2023-07-03 application/pdf http://www.osti.gov/servlets/purl/1609579 https://www.osti.gov/biblio/1609579 https://doi.org/10.5194/bg-16-1829-2019 unknown http://www.osti.gov/servlets/purl/1609579 https://www.osti.gov/biblio/1609579 https://doi.org/10.5194/bg-16-1829-2019 doi:10.5194/bg-16-1829-2019 59 BASIC BIOLOGICAL SCIENCES 54 ENVIRONMENTAL SCIENCES 2023 ftosti https://doi.org/10.5194/bg-16-1829-2019 2023-07-11T09:41:06Z In response to a warming climate, temperature extremes are changing in many regions of the world. Therefore, understanding how the fluxes of sensible heat, latent heat and net ecosystem exchange respond and contribute to these changes is important. We examined 216 sites from the open access Tier 1 FLUXNET2015 and free fair-use La Thuile data sets, focussing only on observed (non-gap-filled) data periods. We examined the availability of sensible heat, latent heat and net ecosystem exchange observations coincident in time with measured temperature for all temperatures, and separately for the upper and lower tail of the temperature distribution, and expressed this availability as a measurement ratio. We showed that the measurement ratios for both sensible and latent heat fluxes are generally lower (0.79 and 0.73 respectively) than for temperature measurements, and the measurement ratio of net ecosystem exchange measurements are appreciably lower (0.42). However, sites do exist with a high proportion of measured sensible and latent heat fluxes, mostly over the United States, Europe and Australia. Few sites have a high proportion of measured fluxes at the lower tail of the temperature distribution over very cold regions (e.g. Alaska, Russia) or at the upper tail in many warm regions (e.g. Central America and the majority of the Mediterranean region), and many of the world's coldest and hottest regions are not represented in the freely available FLUXNET data at all (e.g. India, the Gulf States, Greenland and Antarctica). However, some sites do provide measured fluxes at extreme temperatures, suggesting an opportunity for the FLUXNET community to share strategies to increase measurement availability at the tails of the temperature distribution. We also highlight a wide discrepancy between the measurement ratios across FLUXNET sites that is not related to the actual temperature or rainfall regimes at the site, which we cannot explain. Our analysis provides guidance to help select eddy covariance sites for researchers ... Other/Unknown Material Antarc* Antarctica Greenland Alaska SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Greenland Biogeosciences 16 8 1829 1844 |
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Open Polar |
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SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
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ftosti |
language |
unknown |
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59 BASIC BIOLOGICAL SCIENCES 54 ENVIRONMENTAL SCIENCES |
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59 BASIC BIOLOGICAL SCIENCES 54 ENVIRONMENTAL SCIENCES van der Horst, Sophie V. J. Pitman, Andrew J. De Kauwe, Martin G. Ukkola, Anna Abramowitz, Gab Isaac, Peter How representative are FLUXNET measurements of surface fluxes during temperature extremes? |
topic_facet |
59 BASIC BIOLOGICAL SCIENCES 54 ENVIRONMENTAL SCIENCES |
description |
In response to a warming climate, temperature extremes are changing in many regions of the world. Therefore, understanding how the fluxes of sensible heat, latent heat and net ecosystem exchange respond and contribute to these changes is important. We examined 216 sites from the open access Tier 1 FLUXNET2015 and free fair-use La Thuile data sets, focussing only on observed (non-gap-filled) data periods. We examined the availability of sensible heat, latent heat and net ecosystem exchange observations coincident in time with measured temperature for all temperatures, and separately for the upper and lower tail of the temperature distribution, and expressed this availability as a measurement ratio. We showed that the measurement ratios for both sensible and latent heat fluxes are generally lower (0.79 and 0.73 respectively) than for temperature measurements, and the measurement ratio of net ecosystem exchange measurements are appreciably lower (0.42). However, sites do exist with a high proportion of measured sensible and latent heat fluxes, mostly over the United States, Europe and Australia. Few sites have a high proportion of measured fluxes at the lower tail of the temperature distribution over very cold regions (e.g. Alaska, Russia) or at the upper tail in many warm regions (e.g. Central America and the majority of the Mediterranean region), and many of the world's coldest and hottest regions are not represented in the freely available FLUXNET data at all (e.g. India, the Gulf States, Greenland and Antarctica). However, some sites do provide measured fluxes at extreme temperatures, suggesting an opportunity for the FLUXNET community to share strategies to increase measurement availability at the tails of the temperature distribution. We also highlight a wide discrepancy between the measurement ratios across FLUXNET sites that is not related to the actual temperature or rainfall regimes at the site, which we cannot explain. Our analysis provides guidance to help select eddy covariance sites for researchers ... |
author |
van der Horst, Sophie V. J. Pitman, Andrew J. De Kauwe, Martin G. Ukkola, Anna Abramowitz, Gab Isaac, Peter |
author_facet |
van der Horst, Sophie V. J. Pitman, Andrew J. De Kauwe, Martin G. Ukkola, Anna Abramowitz, Gab Isaac, Peter |
author_sort |
van der Horst, Sophie V. J. |
title |
How representative are FLUXNET measurements of surface fluxes during temperature extremes? |
title_short |
How representative are FLUXNET measurements of surface fluxes during temperature extremes? |
title_full |
How representative are FLUXNET measurements of surface fluxes during temperature extremes? |
title_fullStr |
How representative are FLUXNET measurements of surface fluxes during temperature extremes? |
title_full_unstemmed |
How representative are FLUXNET measurements of surface fluxes during temperature extremes? |
title_sort |
how representative are fluxnet measurements of surface fluxes during temperature extremes? |
publishDate |
2023 |
url |
http://www.osti.gov/servlets/purl/1609579 https://www.osti.gov/biblio/1609579 https://doi.org/10.5194/bg-16-1829-2019 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Antarc* Antarctica Greenland Alaska |
genre_facet |
Antarc* Antarctica Greenland Alaska |
op_relation |
http://www.osti.gov/servlets/purl/1609579 https://www.osti.gov/biblio/1609579 https://doi.org/10.5194/bg-16-1829-2019 doi:10.5194/bg-16-1829-2019 |
op_doi |
https://doi.org/10.5194/bg-16-1829-2019 |
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Biogeosciences |
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16 |
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8 |
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1829 |
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1844 |
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