The research team analyzed 965 cases of changes in river water quality during a variety of extreme weather conditions, including droughts, heat waves, heavy rains, floods and long-term climate change. Their findings revealed a worrying trend: river water quality is deteriorating after severe weather events.
“We looked at different components of water quality, such as water temperature, dissolved oxygen, salinity, and the concentration of nutrients, metals, microorganisms, pharmaceuticals, and plastics,” explained Dr. van Vliet.
The analysis showed that in most cases water quality deteriorates during droughts and heat waves (68%), storms and floods (51%) and long-term climate change (56%). During drought, the limited availability of water makes diluting pollutants challenging. In contrast, heavy rains and floods often lead to more pollutants running off the land into rivers and streams.
Although some cases reported improvements in water quality or variable responses due to countermeasures such as increased pollutant transport offset by increased dilution during floods, the overall trend was worrisome.
The study emphasized that changes in river flow and water temperature, which are affected by factors such as land use and human activities such as sewage treatment, play a significant role in changes in water quality. Understanding the complex interactions between climate, land use and anthropogenic factors is critical to effectively addressing this problem.
In addition, the study called for more data collection and studies on water quality in countries other than Western countries. “We need better monitoring of water quality in Africa and Asia. Most water quality studies now focus on rivers and streams in North America and Europe,” emphasized Dr. van Vliet.
In summary, the study highlights the urgent need to better understand changes in water quality during extreme weather events and the underlying mechanisms. Only with this information can effective water management strategies be developed to secure the availability of clean water and ensure the health of the ecosystem due to climate change and increasing weather conditions.
HT
Source: The Nordic Page