Hydrology of the Great Barrier Reef catchment area along a latitudinal gradient: Implications for estimating discharge

Study region: Great Barrier Reef catchment, north-eastern Australia Study Focus: The Great Barrier Reef (GBR) catchment of north-eastern Australia contains 35 separate river basins comprising an area of 423,000 km2. This study compiled flow data for 49 gauging stations to elucidate drivers of hydrologic patterns across the GBR catchment. We compare different methods to upscale annual flow volumes recorded at individual gauging stations to total end of system volumes for the GBR catchment. Accurate estimates of total basin discharge are essential for pinpointing sources of pollution and focussing land management strategies within the GBR. New hydrological insights for the region: Our spatial analysis revealed distinct north-south gradients in the discharge data largely related to rainfall/climate variability. The northern basins generally have higher stream discharge per unit area, lower coefficients of variation for both inter- and intra-annual discharge, higher runoff to rainfall ratios, higher baseflow contributions and fewer zero-flow days relative to basins in the south. River basins deviated from the north-south gradient due to location-specific factors such as basin size, rainfall variability and anthropogenic modification to flow regimes. We provide recommendations on the most appropriate factors to use when scaling up the gauged discharge data to represent total basin discharge. Our study systematically assesses the spatial variability in river discharge statistics across a north-south latitudinal gradient and provides insights on key drivers of hydrological processes.

Journal of Hydrology: Regional Studies

Journal of Hydrology: Regional Studies

61

2214-5818

N/A

N/A

22