Zero day droughts (DZD), Episodes of extreme water foul, will increase considerably in frequency. A study indicates that at the end of the century they can threaten 750 million people and in the next two decades, critical scarcity points in places such as the sea Mediterranean.
The research of the Institute of Basic Sciences of Korea, based on models, provides that the risk of serious water shortage due to climate change affects almost three quarters (74%) of the drought -prone regions, including those with large reservoirs, in a high emissions scenario.
At the end of this century, 753 million people, including 467 million in urban areas such as the Mediterraneanthey could be vulnerable to an extreme shortage of water in case of a heating of 1.5 degrees above the pre -industrial levels, according to the study published by the Nature Magazine.
The Mediterranean region would be the most exposed in urban areas, while the north and southern Africa and some parts of Asia would face the most serious impacts on rural, the aforementioned institute indicates in a statement.
The study shows that the frequency of the DZD will increase “considerably in the coming decades, long earlier than previously planned.”
This is the first known estimate of this type and points out that it is likely that in the decades of 2020 and 2030 critical points of water scarcity arise in the Mediterranean, southern Africa and some areas of North America.
In addition, it warns that the interval between the future DZD could be shorter than the duration of the events, which would aggravate the risks of water shortage by limiting the ability of the regions to recover from drought.
1 /12 | Impressive images of the effects of drought in two rivers in China. A woman uses her smartphone while standing in a rocky outcrop on the Yangtsé river channel in the municipality of Chongqing, in southwest China. – The Associated Press
Research does not take into account the role of groundwater as a shock absorber during droughts.
The study shows that “he global warming It causes and accelerates the drought conditions of zero day worldwide. Even if we reach the objective of 1.5 degrees, hundreds of millions of people will continue to face an unprecedented shortage of water ”said Vecchia Ravinandrasana, first author of the study.
According to calculations, and due to the increase in the severity of hydrological stress, “14 % of the main reservoirs could already dry during their first episodes of drought from zero day, which would have serious repercussions on people’s livelihoods,” added Christian Franzke, another of the signatories.
Cities such as Cape City in 2018 and Chennai, in the India. In 2019 they have already approached DZD conditions, which highlights the growing vulnerability of urban drinking water supply and agriculture systems, highlights the note.
The droughts of zero day “are no longer a distant scenario: they are already happening. Without an immediate adaptation and sustainable water management, it is likely that hundreds of millions of people face an unprecedented shortage of water in the future,” Ravinandrasana added.