Author(s): M. Amghar; C. Thorstensen
Linked Author(s): Mohand Amghar
Keywords: Step-change; Trend; Streamflow; Climate variability; Southeast Queensland
Abstract: Climate is the major source of variability in the timing and the amount of available water resources. The majority of water supplies in Southeast Queensland are derived from cyclone season and deep low pressure storms. This study carried out statistical analyses of long term hydrological data. One hundred years of historical trends in rainfall and streamflow in Southeast Queensland (SEQ) are developed using regression analyses and Mann-Kendall statistics. The results show statistical evidence that some areas in SEQ have experienced a decline in streamflow since 1970, with only a few areas showing a significant increase. The decline may be largely attributed to climate variability, such that more data may see the trend at many sites disappear; however, plausible other causes need to be investigated at each individual site. Evidence of a change in the streamflow regime is seen with the shift in the annual flow that has been observed across all sites. However, the statistical evidence in this current study is not strong enough to base a change for a shorter period since 1970; as, the standard period of analysis should be extended to include all available data post-1970 for water resource management.
Year: 2011