Without water there is no life. But not only too little, but also too much of the life-giving resource can be dangerous. As the World Meteorological Organization’s latest World Water Report shows, both extremes – droughts and floods – are becoming increasingly common. The study authors interpret this as a “distress signal” from the planet that indicates advancing climate change.
Water is equally important for the survival of people and ecosystems. The World Meteorological Organization (WMO) has just reviewed the status of global water resources for the third time and for this purpose has combined measurement data from all over the world, including groundwater data from 35,500 wells, the water levels of 713 rivers and the storage capacities of various lakes and glaciers. The “State of Global Water Resources 2023” is the most comprehensive report on how our planet’s water resources fared last year.
Extremes continue to increase
The key message of the report: 2023 was a year of extremes. With an average temperature of 1.45 degrees above pre-industrial levels, it was the warmest year on record, which led to increased droughts and, paradoxically, more floods. “A warmer atmosphere retains more moisture, which promotes heavy rainfall. The faster evaporation and drying of the soil in turn worsen the drought conditions,” explains WMO Secretary-General Celeste Saulo.
Some regions were particularly hard hit by these extreme weather events. For example, the southern United States, Central America, Argentina, Uruguay, Peru and Brazil suffered from extreme drought. In Argentina, the drought even led to a three percent drop in gross domestic product, while the lowest water levels ever recorded were recorded in the Amazon and Lake Titicaca. Other regions were plagued by extreme rainfall, which led to flooding in many places. In Libya, for example, two dams burst as a result of a major flood, killing more than 11,000 people.
No end in sight
“Either too dry or too wet, neither is good. Unfortunately, it is to be expected that we will experience both extremes even more frequently as temperatures rise worldwide,” explains Earth system scientist Robert Reinecke from the University of Mainz. Saulo adds: “Water is the canary in the coal mine of climate change. We are receiving distress signals in the form of increasingly extreme rainfall, floods and droughts that are placing severe strain on lives, ecosystems and economies.”
In some places, the effects of climate change were further exacerbated last year by the natural weather phenomenon El Niño, which occurs every two to seven years due to changing air currents over the tropical Pacific. During an El Niño, the sea off South America warms, which in turn disrupts weather patterns around the world. The Amazon region, for example, is experiencing extreme drought, while East Africa is struggling with enormous amounts of rain. El Niño may be over now, but climate change continues. Therefore, there will be no all-clear for the extreme precipitation events for the time being.
Source: Johannes Gutenberg University Mainz, World Meteorological Organization (WMO); State of Global Water Resources 2023 (PDF)