World water resources decreasing as global rivers dry up
“Water is the canary in the coal mine of climate change,” said Celeste Saulo, WMO secretary-general. “Water is the basis of life on this planet, but it can also be a force of destruction.”
She told journalists at a briefing in Geneva that “water is becoming increasingly unpredictable, what we call an erratic hydrological cycle, leading to extreme rainfall, sudden floods, and severe droughts.”
“Climate change is one of the causes of these extreme behaviors,” she said, noting that these extreme events “wreak a heavy toll on lives, ecosystems and economies.”
“Melting ice and glaciers threaten long-term water security for many millions of people. And yet we are not taking the necessary urgent action,” she warned.
“To mitigate the impact of such potential catastrophes, we must gather reliable data. After all, we cannot appropriately manage what we do not measure,” she said, adding that scientific data gathered by WMO “indicates the situation will worsen over the coming years.”
The report finds 2023 was the driest year for global rivers in 33 years, marking the last of five consecutive years of widespread below-normal conditions for river flows, thereby reducing “the amount of water available for communities, agriculture and ecosystems, further stressing global water supplies.”
It notes that 2023 was also the second consecutive year in which all regions in the world with glaciers reported ice loss, the year in which “glaciers suffered the largest mass loss ever registered in 50 years.”
“The glaciers are retreating rapidly,” said Stefan Uhlenbrook, WMO director of hydrology, water and cryosphere. “The latest data for this year actually shows that in the Swiss Alps, at least, it has been continuing and more glaciers have been reduced.
“If a glacier is melting more and more, that means more water becomes available downstream,” he said. “However, if the glacier is gone in a few more decades, it will be very dramatic because then the summer high flows from the melting glaciers will disappear because there is no storage anymore.
“If the glacier disappears, that changes completely the hydrological regime. It changes completely the conditions for ecosystems. It changes completely the availability of water for farmers. So, it has really severe consequences,” he said.
One manifestation of this was seen last week when Switzerland and Italy redrew part of their shared border in the Alps because melting glaciers due to climate change had moved their long-defined national border.
The report says 3.6 billion people currently face inadequate access to water at least one month a year, and this is expected to increase to more than 5 billion by 2050.
While no region is spared from disastrous hydrological extreme events, it says floods and droughts affected Africa most in terms of human casualties. The report says major flooding in Libya due to two collapsed dams, triggered by Storm Daniel, killed more than 11,000 people. Floods also impacted the Greater Horn of Africa, Democratic Republic of Congo, Rwanda, Mozambique and Malawi.
“Jordan is one of the most water scarce countries because of the high population density and the very arid conditions,” Uhlenbrook observed, adding that many parts of Asia, North and South America, and Russia among other regions are “very vulnerable to the changes we see from climate change.”
“We see the increasing variability of the hydrological cycle causing tension and stress and providing the source of conflict in many parts of the world,” he said.
The WMO report is calling for urgent action and international cooperation to address the scarce water issues. It says cooperation through data sharing and building of trust between nations is critical for managing shared water resources.
“We must fill the gaps in our understanding. We need to expand our hydrological monitoring, especially in regions where data is scarce. We cannot afford blind spots when it comes to our water resources,” WMO chief Saulo said. “I urge nations to invest in hydrological monitoring and commit to sharing this critical data, because without it, we are navigating without a map.”
She underscored the importance of early warning systems in addressing climate-induced disasters such as floods and extreme weather events. “These global challenges transcend borders and conflicts because water is once again the basis of life on Earth, so we must work together to address the water issues,” she said.