Climate change and the Rhine


There are all kinds of consequences all over the world. But what does climate change mean for the Rhineland?

The catchment area of the Rhine has various climates, with the continental climate being the most common.

Read more about the climates in the catchment area.

On average, more precipitation falls in the catchment area in winter than in summer. The river then has to carry more water, and there is a greater chance of high water. This is defined as water levels being higher than normal for eight days in a row.

So when there is high water, the Rhine has to carry more water. But the river does not get any wider. The water has nowhere to go apart from with the current. It flows faster and becomes stronger.

Read more about high water.

There can be heavy rainfall in summer, but there is less precipitation at this time of year than in winter. This means that there is less water flowing through the river, and a greater chance of low water.

Read more about low water.

In the Alps it is the other way round. This area has a high mountain climate. Lots of snow falls in the mountains in winter. Snow settles on the ground, and so the precipitation does not end up in the Rhine. This means that less water passes through the Rhine. The snow melts in summer, and there is a lot of rain at this time, which means that there is more water in the Rhine. 

Alpenrhein (Foto: www.hydra-institute.com)
[Translate to en:] Alpenrhein
Foto: www.hydra-institute.com

 

Water temperature and water quality

The temperature on earth is rising, and so the water in the Rhine is getting warmer too. The sun heats the water. Scientists think that the water in the Rhine will be on average 3.5 degrees warmer than it is now in about 80 years time. Water temperature is important for water quality. Hotter water contains less oxygen, and oxygen is vital to the plants and animals that live in the water.

Plants and animals are sensitive to water temperature. Fish have no body heat of their own, they take on the temperature of the water they are in. Cold-water fish like salmon need temperatures that do not exceed 21?C, while for warm-water fish like carp the limit is 28?C.

If the water is much warmer than this for a long time, the fish will die.

Read more about water quality.

Zalm (Foto: U. Haufe)
Salmon Foto: U. Haufe

 

The quantity of water

The water level in the Rhine rises if there is a lot of rain, snow or hail, and falls if there is not very much. Both high water and low water have all kinds of consequences for the Rhine.

For example, it can be too dangerous for ships to travel on the river at high water. Shipping is sometimes completely banned for a time because the water is flowing too fast or because ships can no longer get under bridges safely. Low water can also cause problems for shipping. The water has to be deep enough for large vessels and their heavy cargo. Low water can mean that you cannot put as much cargo on your ships, and so you have to make more journeys.

Containerschiff (foto: D. Putscher)
[Translate to en:] Containerschiff (foto: D. Putscher)
Containerschiff  (foto: D. Putscher)
[Translate to en:] Containerschiff
Foto: D. Putscher


In some areas farmers use river water to irrigate their crops. They don’t like low water either, because they need to have enough water to spray on their land and crops. If there is not enough water, the harvest might fail.

Most animals in the Rhine have no problems with high water. More water means more space, and most animals like that.

In low water, animals are more closely packed together and this can lead to the spread of disease among other problems.

Water plants do best if the water level does not vary too much within a year. But most plants do always return after a period of high or low water in which they were unable to survive.

Read more about the consequences of high water and low water.

Droogte (Foto: D. van Rossum)
drought Foto: D. van Rossum