The Guardian - Alerte climatique : les rivières du monde s'assèchent au rythme le plus rapide depuis 30 ans
“We receive distress signals in the form of increasingly extreme rainfall, floods and droughts which 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.”
A tugboat navigates around sandbars amid low water levels on the Mississippi River. Water levels on the river hit a record low in 2023. Photograph: Gerald Herbert/AP
Cet article récent du Guardian fait état de la vitesse alarmante à laquelle les cours d'eau de la planète s'assèchent, l'année 2023 marquant le déclin le plus rapide depuis 30 ans. L'Organisation météorologique mondiale (OMM) a publié son rapport sur l'état des ressources mondiales en eau, qui révèle que plus de 50 % des bassins hydrographiques de la planète étaient déficitaires l'année dernière. De grands fleuves tels que l'Amazone, le Mississippi, le Gange et le Mékong ont atteint des niveaux d'eau historiquement bas, menaçant la sécurité de l'eau pour des millions de personnes.
“As a result of rising temperatures, the hydrological cycle has accelerated. It has also become more erratic and unpredictable, and we are facing growing problems of either too much or too little water. A warmer atmosphere holds more moisture which is conducive to heavy rainfall. More rapid evaporation and drying of soils worsen drought conditions”
The report attributes these extreme conditions to climate breakdown, with 2023 also being the hottest year on record. The shift from La Niña to El Niño mid-year contributed to widespread droughts and devastating floods. In regions like North and South America, Asia, and Oceania, rivers ran dry, while countries such as New Zealand, the Philippines, and parts of Africa faced destructive floods. This dual threat of too much and too little water underscores the volatility of the global water cycle as temperatures rise.
WMO Secretary-General Celeste Saulo warned that water is the "canary in the coalmine of climate change," pointing to the urgent need for action. Rising global temperatures are accelerating the hydrological cycle, resulting in unpredictable rainfall, more frequent droughts, and faster melting of glaciers. Alarmingly, glaciers worldwide lost over 600 gigatonnes of water in 2023, with Switzerland’s Alps losing 10% of their volume in the past two years.
As we navigate the growing complexities of water resource management in an era of climate volatility, ongoing initiatives like the Canada1Water project (C1W) are essential. C1W provides critical data and insights into the impacts of climate change on Canada’s water systems, offering a vital resource for decision-makers seeking to develop sustainable water management strategies and ensure long-term water security for the country.