Search

This paper presents the spatial variation of area‐orientated annual maximum daily rainfall (AMDR), represented by well‐fitted generalized extreme value (GEV) distributions, over the last century in Great Britain (GB) and Australia (AU) with respect to three spatial properties: geographic locations, sizes, and shapes of the region‐of‐interest (ROI). The results show that the spatial variation of GEV location‐scale parameters is dominated by geographic locations and area sizes. In GB, there is an eastward‐decreasing banded pattern compared with a concentrically increasing pattern from the middle to coasts in AU. The parameters tend to decrease with increased area sizes in both studied regions. Although the impact of the ROI shapes is insignificant, the round‐shaped regions usually have higher‐valued parameters than the elongated ones. These findings provide a new perspective to understand the heterogeneity of extreme rainfall distribution over space driven by the complex interactions between climate, geographical features, and the practical sampling approaches. Key Points: Rainfall series are extracted and processed from more than 11,000 regions of interest over the last 100 years in Great Britain and Australia.Spatial distribution of extreme rainfall modeled qualitatively and quantitatively shows impact from location, size, and shape of regions.Methods and findings provide new perspectives for understanding the heterogeneous nature of climate variability and climatic change impact. [ABSTRACT FROM AUTHOR]

Due to significant weather variabilities of rainfalls, potential water savings through rainwater tanks are expected to vary significantly. Moreover, within some large cities, significant spatial variations are reported. With the emerging impacts of climate change, existing weather and spatial variabilities of potential water savings are also likely to be changed, which are unknown to the end-users. This paper presents the impacts of climate change on current weather and spatial variabilities of potential water savings for Adelaide, a large city in Australia. Future daily rainfall data was collected from a data portal provided by the Australian government derived through a statistical downscaling modelling. Projected daily rainfall data was fed to an earlier developed daily water balance model (eTank) to calculate water savings for three future periods; 2030–2050, 2055–2075 and 2080–2100. Three weathers (dry, average and wet) in each period were considered along with two climate change scenarios (RCP 4.5 and RCP 8.5) and two tank sizes (5 kL and 10 kL). It is found that varying outcomes without any general trend are expected depending on the projection scenario, period and weather condition. Contrary to the general perception, it is found that in several cases, the potential water savings are expected to increase compared to the current climate. Most of those expected increases in water savings are attributed to the projection scenario of RCP 4.5, in the near future and in dry years. In the far-future and with the projection scenario of RCP 8.5, most of the potential water savings are expected to decrease compared to the current climate. Regarding changes in spatial variability of water savings, it is found that the spatial variability will decrease in the near future, but will increase towards the far future. [ABSTRACT FROM AUTHOR]