On the use of the post-closure methods uncertainty band to evaluate the performance of land surface models against eddy covariance flux data
The energy balance of eddy covariance (EC) flux data is normally not closed. Therefore, at least if used for modelling, EC flux data are usually post-closed, i.e. the measured turbulent fluxes are adjusted so as to close the energy balance. At the current state of knowledge, however, it is not clear...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2015-04-01
|
| Series: | Biogeosciences |
| Online Access: | http://www.biogeosciences.net/12/2311/2015/bg-12-2311-2015.pdf |
| _version_ | 1811338732646694912 |
|---|---|
| author | J. Ingwersen K. Imukova P. Högy T. Streck |
| author_facet | J. Ingwersen K. Imukova P. Högy T. Streck |
| author_sort | J. Ingwersen |
| collection | DOAJ |
| description | The energy balance of eddy covariance (EC) flux data is normally not closed.
Therefore,
at least if used for modelling, EC flux data are usually post-closed, i.e.
the measured
turbulent fluxes are adjusted so as to close the energy balance. At the
current state of
knowledge, however, it is not clear how to partition the missing energy in
the right way.
Eddy flux data therefore contain some uncertainty due to the unknown nature
of the
energy balance gap, which should be considered in model evaluation and the
interpretation of simulation results. We propose to construct the
post-closure methods
uncertainty band (PUB), which essentially designates the differences between
non-adjusted flux data and flux data adjusted with the three post-closure
methods (Bowen ratio, latent heat flux (LE) and sensible heat flux (<i>H</i>)
method). To demonstrate this approach, simulations with the NOAH-MP land
surface model were evaluated based on EC measurements conducted at a winter
wheat stand in southwest Germany in 2011, and the performance of the Jarvis
and Ball–Berry stomatal resistance scheme was compared. The width of the PUB
of the LE was up to 110 W m<sup>−2</sup> (21% of net radiation). Our study
shows that it is crucial to account for the uncertainty in EC flux data
originating from lacking energy balance closure. Working with only a single
post-closing method might result in severe misinterpretations in model–data
comparisons. |
| first_indexed | 2024-04-13T18:15:29Z |
| format | Article |
| id | doaj.art-c1e75db20e1749b6900af691f4959745 |
| institution | Directory Open Access Journal |
| issn | 1726-4170 1726-4189 |
| language | English |
| last_indexed | 2024-04-13T18:15:29Z |
| publishDate | 2015-04-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Biogeosciences |
| spelling | doaj.art-c1e75db20e1749b6900af691f49597452022-12-22T02:35:42ZengCopernicus PublicationsBiogeosciences1726-41701726-41892015-04-011282311232610.5194/bg-12-2311-2015On the use of the post-closure methods uncertainty band to evaluate the performance of land surface models against eddy covariance flux dataJ. Ingwersen0K. Imukova1P. Högy2T. Streck3Institute of Soil Science and Land Evaluation, Universität Hohenheim, 70593 Stuttgart, GermanyInstitute of Soil Science and Land Evaluation, Universität Hohenheim, 70593 Stuttgart, GermanyInstitute of Landscape and Plant Ecology, Universität Hohenheim, 70593 Stuttgart, GermanyInstitute of Soil Science and Land Evaluation, Universität Hohenheim, 70593 Stuttgart, GermanyThe energy balance of eddy covariance (EC) flux data is normally not closed. Therefore, at least if used for modelling, EC flux data are usually post-closed, i.e. the measured turbulent fluxes are adjusted so as to close the energy balance. At the current state of knowledge, however, it is not clear how to partition the missing energy in the right way. Eddy flux data therefore contain some uncertainty due to the unknown nature of the energy balance gap, which should be considered in model evaluation and the interpretation of simulation results. We propose to construct the post-closure methods uncertainty band (PUB), which essentially designates the differences between non-adjusted flux data and flux data adjusted with the three post-closure methods (Bowen ratio, latent heat flux (LE) and sensible heat flux (<i>H</i>) method). To demonstrate this approach, simulations with the NOAH-MP land surface model were evaluated based on EC measurements conducted at a winter wheat stand in southwest Germany in 2011, and the performance of the Jarvis and Ball–Berry stomatal resistance scheme was compared. The width of the PUB of the LE was up to 110 W m<sup>−2</sup> (21% of net radiation). Our study shows that it is crucial to account for the uncertainty in EC flux data originating from lacking energy balance closure. Working with only a single post-closing method might result in severe misinterpretations in model–data comparisons.http://www.biogeosciences.net/12/2311/2015/bg-12-2311-2015.pdf |
| spellingShingle | J. Ingwersen K. Imukova P. Högy T. Streck On the use of the post-closure methods uncertainty band to evaluate the performance of land surface models against eddy covariance flux data Biogeosciences |
| title | On the use of the post-closure methods uncertainty band to evaluate the performance of land surface models against eddy covariance flux data |
| title_full | On the use of the post-closure methods uncertainty band to evaluate the performance of land surface models against eddy covariance flux data |
| title_fullStr | On the use of the post-closure methods uncertainty band to evaluate the performance of land surface models against eddy covariance flux data |
| title_full_unstemmed | On the use of the post-closure methods uncertainty band to evaluate the performance of land surface models against eddy covariance flux data |
| title_short | On the use of the post-closure methods uncertainty band to evaluate the performance of land surface models against eddy covariance flux data |
| title_sort | on the use of the post closure methods uncertainty band to evaluate the performance of land surface models against eddy covariance flux data |
| url | http://www.biogeosciences.net/12/2311/2015/bg-12-2311-2015.pdf |
| work_keys_str_mv | AT jingwersen ontheuseofthepostclosuremethodsuncertaintybandtoevaluatetheperformanceoflandsurfacemodelsagainsteddycovariancefluxdata AT kimukova ontheuseofthepostclosuremethodsuncertaintybandtoevaluatetheperformanceoflandsurfacemodelsagainsteddycovariancefluxdata AT phogy ontheuseofthepostclosuremethodsuncertaintybandtoevaluatetheperformanceoflandsurfacemodelsagainsteddycovariancefluxdata AT tstreck ontheuseofthepostclosuremethodsuncertaintybandtoevaluatetheperformanceoflandsurfacemodelsagainsteddycovariancefluxdata |