20 March 2020
The United Nations’ World Water Day takes place on the 22 March every year, the aim being to focus attention on the importance of water. The theme for 2020 is ‘Water and Climate Change.’ In this article we look at research which asks; ‘Can we address climate change without sacrificing water quality?’
According to a study published during 2019, strategies for limiting climate change must take into account their potential impact on water quality through nutrient overload. Rainfall and other precipitation wash nutrients from human activities such as agriculture into waterways. This excessive richness of nutrients in a body of water is called eutrophication, which can lead to algal blooms and produce toxins or low-oxygen dead zones.
Researchers from Carnegie Institute for Science, US, have been considering how various societal decisions about land use, development, agriculture and climate mitigation could affect the ‘already complex equation of projecting future risks to water quality throughout continental US.’ Climate change-related differences in precipitation patterns, which would additionally contribute to the overall water quality risk, were factored in.
The research team found that climate change mitigation efforts that relied heavily on biofuels could have the unintended consequence of increasing the amount of nitrogen entering US waterways, causing water quality problems. In addition, scenarios that required a large increase in domestic food production would increase both fossil fuel emissions and water quality problems. It was found that the most successful scenarios relied on sustainable growth and conservation.
Looking beyond the US, the researchers said that Asia would be at the greatest risk of eutrophication due to projected increases in fertiliser use and anticipated increases in rainfall.
‘Our findings show that it is crucial to consider the potential for water quality impairments when making societal choices about how land is used and developed, as well as about how we work to fight climate change,’ the researchers said. ‘Access to clean water is essential for human survival, food and energy production and a healthy ecosystem. Preserving our ability to access clean water must be a top priority,’ they added.