The year 2019 will live long in the memory of Australians – the hottest and driest year on record, where towns ran out of water and bushfires destroyed thousands of homes. But this is just the beginning, with this decade likely to be the coolest this century.
“Climate-related risks and opportunities are undeniably intertwined with those associated with water. Any assessments of future water-related events should therefore consider the climate, but this is only one piece of the puzzle. Other socio-economic drivers impact the supply and demand of water, such as regulatory, market and demographic changes. The new WWF Water Risk Filter tool supports the integration of water into TCFD-aligned scenario analysis and will strengthen the disclosure and assessment of companies’ resilience to future scenarios,” said Francesca Recanati, Environmental Specialist (Technical Manager), Climate Disclosure Standards Board (CDSB).
Extreme droughts are likely to become much more frequent across central Europe, which threaten ecosystem and human health, and economic wellbeing. If global greenhouse gas emissions rise strongly, a seven times increase in droughts could happen new research has shown.
Planning for the future in coastal communities will mean accounting for rising seas levels, which are bringing water into communities at record rates. Forward-looking scenarios like those developed by Riskthinking.AI can help decision-makers uncover the risks and plan accordingly.
Both seasonal and annual mean precipitation and evaporation influence patterns of water availability impacting society and ecosystems. Existing global climate studies rarely consider such patterns from non-parametric statistical standpoint. Here, we employ a non-parametric analysis framework to analyze seasonal hydroclimatic regimes by classifying global land regions into nine regimes using late 20th century precipitation means and seasonality. These regimes are used to assess implications for water availability due to concomitant changes in mean and seasonal precipitation and evaporation changes using CMIP5 model future climate projections. Out of 9 regimes, 4 show increased precipitation variation, while 5 show decreased evaporation variation coupled with increasing mean precipitation and evaporation. Increases in projected seasonal precipitation variation in already highly variable precipitation regimes gives rise to a pattern of “seasonally variable regimes becoming more variable”. Regimes with low seasonality in precipitation, instead, experience increased wet season precipitation.
Various transboundary river basins are facing increased pressure on water resources in near future. However, little is known ab out the future drivers globally, namely, changes in natural local runoff and natural inflows from upstream parts of a basin, as well as local and upstream water consumption. Here we use an ensemble of four global hydrological models forced by five global climate models and the latest greenhouse‐gas concentration (RCP) and socioeconomic pathway (SSP) scenarios to assess the impact of these drivers on transboundary water stress in the past and future. Our results show that population under water stress is expected to increase by 50% under a low population growth and emissions scenario (SSP1‐RCP2.6) and double under a high population growth and emission scenario (SSP3‐RCP6.0), compared to the year 2010. As changes in water availability have a smaller effect when water is not yet scarce, changes in water stress globally are dominated by local water consumption—managing local demand is thus necessary in order to avoid future stress. Focusing then on the role of upstream changes, we identified upstream availability (i.e., less natural runoff or increased water consumption) as the dominant driver of changes in net water availability in most downstream areas. Moreover, an increased number of people will be living in areas dependent on upstream originating water in 2050. International water treaties and management will therefore have an increasingly crucial role in these hot spot regions to ensure fair management of transboundary water resources.
Within the Colorado River basin, management laws dictate how water is allocated to farms, businesses and homes. Those laws, along with changing climate patterns and demand for water, form a complex dynamic that has made it difficult to predict who will be hardest hit by drought.