30. Oktober 2023 | The 2022 report by the World Meteorological Organization (WMO) reveals a concerning increase in global dry conditions, with nearly 40% of examined territories experiencing lower than normal water levels, significantly impacting river flow rates and soil moisture.

The second report on the global water resources was recently unveiled by the World Meteorological Organization (WMO). The report indicates that in 2022, many regions of the world were drier than the average conditions recorded for the same periods over the past three decades.

Significant findings and collaborations in the WMO report

Professor Robert Reinecke of Johannes Gutenberg University Mainz (JGU) stated, “Nearly 40 percent of the territories examined were suffering from drier than normal conditions.” He added, “This means that the flow rate of many rivers worldwide was significantly below what would normally be expected. Added to this, the levels of moisture in the soil were frequently indicative of the effects of the heatwaves we have experienced while the need for greater use of water has resulted in the groundwater table becoming lower than in the reference period.”

Professor Reinecke, who became a part of JGU Institute of Geography in May 2023, played a significant role in this new WMO report. He collaborated with Dr. Hannes Müller Schmied of Goethe University Frankfurt, Senckenberg Leibniz Biodiversity and Climate Research Center Frankfurt (SBiK-F), and Global Runoff Database Center (GRDC) in Koblenz. They collectively contributed simulation data based on hydrological modeling, helped develop the corresponding methodology, and validated the key findings of the report scientifically. The WMO coordinated this report, which is a culmination of contributions from 11 international modeling groups.

Unveiling the state of global water resources: Insights and challenges?

In late November 2022, the inaugural State of Global Water Resources Report was unveiled at the WMO headquarters in Geneva. This report, which is set to be released annually, offers a comprehensive overview of the Earth’s water resources. It highlights how climatic changes and fluctuations manifest in our water systems – for instance, heatwaves and droughts can increase the likelihood of wildfires, which can then spread more rapidly due to the lack of soil moisture. “The WMO report is thus also designed to provide politicians and the industry with knowledge so as to identify regions that are at risk of experiencing water emergencies or are already in crisis,” Reinecke emphasized.

The 2022 report presents data on various aspects such as river discharge rates, groundwater levels, soil moisture, and evaporation. However, generating this data is challenging due to the current lack of global statistics.

“Thus, we need to undertake simulation modeling,” Reinecke, an expert in modeling techniques, clarified.

Groundwater data is particularly scarce. Even Germany is unable to provide comprehensive data on this matter. Nonetheless, it’s clear that the dry conditions in 2022 significantly affected Germany as well. Similar to the situation with Italy’s River Po, the Rhine’s water levels dropped dramatically for extended periods, impacting river traffic. France faced challenges in cooling its nuclear power plants due to insufficient rainfall. South America was hit by severe droughts while groundwater levels in Australia’s crucial Murray-Darling Basin continued to fall below normal despite increased rainfall.