Uncertainty in hydrological signatures
Information about rainfall–runoff processes is essential for hydrological analyses, modelling and water-management applications. A hydrological, or diagnostic, signature quantifies such information from observed data as an index value. Signatures are widely used, e.g. for catchment classification, m...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2015-09-01
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| Series: | Hydrology and Earth System Sciences |
| Online Access: | http://www.hydrol-earth-syst-sci.net/19/3951/2015/hess-19-3951-2015.pdf |
| _version_ | 1818484338616958976 |
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| author | I. K. Westerberg H. K. McMillan |
| author_facet | I. K. Westerberg H. K. McMillan |
| author_sort | I. K. Westerberg |
| collection | DOAJ |
| description | Information about rainfall–runoff processes is essential for hydrological
analyses, modelling and water-management applications. A hydrological, or
diagnostic, signature quantifies such information from observed data as an
index value. Signatures are widely used, e.g. for catchment
classification, model calibration and change detection. Uncertainties in the
observed data – including measurement inaccuracy and representativeness as
well as errors relating to data management – propagate to the signature
values and reduce their information content. Subjective choices in the
calculation method are a further source of uncertainty.
<br><br>
We review the uncertainties relevant to different signatures based on
rainfall and flow data. We propose a generally applicable method to calculate
these uncertainties based on Monte Carlo sampling and demonstrate it in two
catchments for common signatures including rainfall–runoff thresholds,
recession analysis and basic descriptive signatures of flow distribution and
dynamics. Our intention is to contribute to awareness and knowledge of
signature uncertainty, including typical sources, magnitude and methods for
its assessment.
<br><br>
We found that the uncertainties were often large (i.e. typical intervals of
±10–40 % relative uncertainty) and highly variable between
signatures. There was greater uncertainty in signatures that use
high-frequency responses, small data subsets, or subsets prone to measurement
errors. There was lower uncertainty in signatures that use spatial or
temporal averages. Some signatures were sensitive to particular uncertainty
types such as rating-curve form. We found that signatures can be designed to
be robust to some uncertainty sources. Signature uncertainties of the
magnitudes we found have the potential to change the conclusions of
hydrological and ecohydrological analyses, such as cross-catchment
comparisons or inferences about dominant processes. |
| first_indexed | 2024-12-10T15:54:00Z |
| format | Article |
| id | doaj.art-f582dc62534747bbb4f725c913dc8f2a |
| institution | Directory Open Access Journal |
| issn | 1027-5606 1607-7938 |
| language | English |
| last_indexed | 2024-12-10T15:54:00Z |
| publishDate | 2015-09-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Hydrology and Earth System Sciences |
| spelling | doaj.art-f582dc62534747bbb4f725c913dc8f2a2022-12-22T01:42:42ZengCopernicus PublicationsHydrology and Earth System Sciences1027-56061607-79382015-09-011993951396810.5194/hess-19-3951-2015Uncertainty in hydrological signaturesI. K. Westerberg0H. K. McMillan1Department of Civil Engineering, University of Bristol, Queen's Building, University Walk, Clifton, BS8 1TR, UKNational Institute of Water and Atmospheric Research, P.O. Box 8602, Christchurch, New ZealandInformation about rainfall–runoff processes is essential for hydrological analyses, modelling and water-management applications. A hydrological, or diagnostic, signature quantifies such information from observed data as an index value. Signatures are widely used, e.g. for catchment classification, model calibration and change detection. Uncertainties in the observed data – including measurement inaccuracy and representativeness as well as errors relating to data management – propagate to the signature values and reduce their information content. Subjective choices in the calculation method are a further source of uncertainty. <br><br> We review the uncertainties relevant to different signatures based on rainfall and flow data. We propose a generally applicable method to calculate these uncertainties based on Monte Carlo sampling and demonstrate it in two catchments for common signatures including rainfall–runoff thresholds, recession analysis and basic descriptive signatures of flow distribution and dynamics. Our intention is to contribute to awareness and knowledge of signature uncertainty, including typical sources, magnitude and methods for its assessment. <br><br> We found that the uncertainties were often large (i.e. typical intervals of ±10–40 % relative uncertainty) and highly variable between signatures. There was greater uncertainty in signatures that use high-frequency responses, small data subsets, or subsets prone to measurement errors. There was lower uncertainty in signatures that use spatial or temporal averages. Some signatures were sensitive to particular uncertainty types such as rating-curve form. We found that signatures can be designed to be robust to some uncertainty sources. Signature uncertainties of the magnitudes we found have the potential to change the conclusions of hydrological and ecohydrological analyses, such as cross-catchment comparisons or inferences about dominant processes.http://www.hydrol-earth-syst-sci.net/19/3951/2015/hess-19-3951-2015.pdf |
| spellingShingle | I. K. Westerberg H. K. McMillan Uncertainty in hydrological signatures Hydrology and Earth System Sciences |
| title | Uncertainty in hydrological signatures |
| title_full | Uncertainty in hydrological signatures |
| title_fullStr | Uncertainty in hydrological signatures |
| title_full_unstemmed | Uncertainty in hydrological signatures |
| title_short | Uncertainty in hydrological signatures |
| title_sort | uncertainty in hydrological signatures |
| url | http://www.hydrol-earth-syst-sci.net/19/3951/2015/hess-19-3951-2015.pdf |
| work_keys_str_mv | AT ikwesterberg uncertaintyinhydrologicalsignatures AT hkmcmillan uncertaintyinhydrologicalsignatures |