Scaling relationships between catchment area and peak discharge across the Fitzroy Basin, eastern Australia
Jaffres, Jasmine B.D., Cuff, Chris, and Rasmussen, Cecily E. (2026) Scaling relationships between catchment area and peak discharge across the Fitzroy Basin, eastern Australia. Journal of Hydrology, 675. 135535.
|
PDF (Published Version)
- Published Version
Available under License Creative Commons Attribution Non-commercial. Download (3MB) | Preview |
Abstract
Specific discharge – the flow rate per unit catchment area – highlights the spatial variability of rainfall–runoff events. These events rarely affect entire catchments uniformly, particularly in large river systems such as the Fitzroy Basin in eastern Australia. Using peak historical flow rates from 136 stream gauges, this study evaluates log–log scaling relationships between catchment area and specific discharge across the entire basin and nine major, nested subcatchments. The site-specific historical peaks across such a large and hydrologically diverse basin are used to assess how scaling behaviour varies with operational record length, rainfall extent and subcatchment characteristics. Peak specific discharge exhibits a strong inverse relationship with catchment area, consistent with power-law scaling. However, this relationship is more robust for gauges with longer operational records. Short operational periods reduce the likelihood of capturing rare, high-magnitude flow events and can substantially weaken scaling regressions. The analysis identifies specific gauges that exert disproportionate influence on the fitted exponents, offering practical guidance for gauge selection in future scaling and flood-frequency studies. Accurate estimation of extreme flows is further complicated by highly complex, non-stationary riverbed cross-sections, with some floodplains spanning several kilometres, reducing the reliability of rating curves during major floods. Improved characterisation of peak specific discharge enhances the predictive capacity for extreme flow rates, particularly under projected increases in atmospheric moisture that are likely to amplify peak flows during extreme rainfall events.
| Item ID: | 91454 |
|---|---|
| Item Type: | Article (Research - C1) |
| ISSN: | 0022-1694 |
| Keywords: | Catchment area, Extreme flow events, Fitzroy Basin, Flow–area scaling, Specific discharge, Stream gauge analysis |
| Copyright Information: | © 2026 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/). |
| Date Deposited: | 01 Jul 2026 03:43 |
| FoR Codes: | 37 EARTH SCIENCES > 3707 Hydrology > 370704 Surface water hydrology @ 100% |
| SEO Codes: | 18 ENVIRONMENTAL MANAGEMENT > 1803 Fresh, ground and surface water systems and management > 180399 Fresh, ground and surface water systems and management not elsewhere classified @ 50% 19 ENVIRONMENTAL POLICY, CLIMATE CHANGE AND NATURAL HAZARDS > 1904 Natural hazards > 190404 Hydrological hazards (e.g. avalanches and floods) @ 50% |
| More Statistics |
Actions (Repository Staff Only)
 |
Item Control Page |