2022

Every few years, the IPCC, the UN Intergovernmental Panel on Climate Change, prepares a report on the expected impact of climate change. What is new in the latest report, and what the predictions mean specifically for the Meuse? Thomas Oomen, data analyst at RIWA-Meuse, brings us up to date.

In the most recent, sixth IPCC report that was published in 2022, we can read that, this century, we will be confronted more often and for longer with extreme weather conditions thanks to the heating of the earth. The United Nations' climate organisation does not do any research itself, but it evaluates already-published scientific research about the risks of climate change.

Data analyst Thomas Oomen: "Already in 2022 we had extreme temperatures and long periods of drought in various parts of the world, including Europe, due to which there were historically low groundwater levels and river flow rates. Last year was in fact the driest year in the 21st century in the Netherlands and one of the driest years ever in Belgium." 

Indisputable role of humanity

In comparison to the previous report from 2014, the latest IPCC report contains more advanced scientific research, more exact models and more data, Oomen reports. "The report gives a more exact prediction of the expected temperature increase. The expected temperature rise has a direct influence on the periods of drought and flooding, which are expected to become more severe."

The emphasis on humanity's role in this edition is also greater, for example due to the use of land and water. "It is stated that humanity's role in the heating of the atmosphere, the ocean and the land is 'indisputable'. In the previous report, the term used was 'extremely probable'." 

The latest IPCC report goes further into the socio-economic consequences of climate change worldwide, such as the reducing availability of fresh water, heat waves and long-term drought with failed harvests and famine as a result. "This provides policymakers with the right information to make decisions about how to deal with the consequences of climate change," says Oomen. "It calls for more intensive cooperation and emphasises the importance of developing nature-based solutions: measures featuring nature and water centrally in order to adapt ourselves to the changing climate."

Regional impact

More than the previous one, the sixth edition of the report goes further into the impact of climate change on certain regions, Oomen adds. For example, it contains expectations for North West Europe.

But he also says: "The IPCC report does not zoom in on river basins. It is important to translate the consequences for the Meuse river basin and to obtain more detailed information about the risks of climate change."

Consequences for the Meuse

He mentions the RIBASIM MAAS model from Deltares, which was developed specifically for the Meuse river basin in 2022, commissioned by RIWA-Meuse. And also the climate scenarios from the KNMI and the KMI, the weather institutes of the Netherlands and Belgium. "If the KNMI combines all this data with the new IPCC climate models in the autumn, a good picture will be created of the impact of climate change on the Meuse. In this way, we will know with more certainty what we are going to be faced with."

More focused models and research therefore help to gain insight into the impact of climate change on the Meuse. In order then to go into axction, it is important that this type of model becomes more mainstream, emphasises Oomen, so that staff from different organisations in the water sector understand the models and can make use of them. "Better understanding leads to better decisions. To this end, a bridge needs to be built between science and policy." 

Less quantity and quality

Reports such as this one from the IPCC and also the Deltares model make it clear that we will have less water in rivers such as the Meuse in future. In addition, it is good to realise, explains Oomen, that: "More periods of drought don't only mean that the quality of the water drops, but also that the quality reduces. The concentration of harmful substances can in fact increase if less water flows down the river." 

In recent years, we have often been confronted with periods of drought and low river flows in the Meuse river basin. Oomen: "But floods also arose, as in 2021 in parts of Germany, Wallonia and Limburg in the Netherlands."

Reducing the impact

To deal with low river flows and worsening water quality, drinking water companies have reservoirs, buffers or alternative sources, Oomen says. In dry periods, these serve as backup if drinking water companies can extract no or only limited water from the Meuse to produce drinking water from. 

For this, much cooperation is needed between all the different parties in the water sector, emphasises Oomen. The drinking water companies, water authorities, central government and commerce, also across the borders. 

Agreements about water usage

More international cooperation and dialogue about the Meuse is essential in any event, he considers. "It's important for example to know what is happening in France, because this could have consequences for the users of the water in Belgium and the Netherlands."

It is also important that clear agreements are made about the use of the Meuse water in the entire river basin, adds the data analyst. "This goes further than just drinking water: it's also about water usage by the energy sector, industry, agriculture, shipping and recreation. And not to forget nature."

The United Nations has already been arguing for a while to include the consequences of climate change in agreements about water usage and allocation, concludes Oomen. "The latest scientific knowledge, such as that in this IPCC report, provides a good basis for this."