Our climate mitigation efforts will need to be ocean friendly

Dealing with climate change requires careful attention to impacts on water quality. Climate action could be a threat to water quality due to increased eutrophication that certain decisions entail, a new study in Nature Communications suggests.

Nutrients released by agriculture can leak into waterways and affect the global water cycle where everything leaves a trace. When too many nutrients accumulate in waters, they can lead to eutrophication, algal blooms and dead zones across large bodies of water leading to a stark decline in marine biodiversity.

In their paper  the researchers explored how different decisions regarding development, agriculture, and climate mitigation could affect water quality throughout the continental U.S. in the near future. Based on six unique development pathways and possible climate outcomes, the researchers found out that potential nitrogen releases into water sources could vary from a 54% increase to a 7% decrease depending on the decisions we make regarding climate action.

According to the team, climate change mitigation efforts based on biofuels could increase the amount of nitrogen entering waterways, threatening water quality. Meanwhile, expanding domestic food production might also lead to increased nitrogen loads, in addition to causing higher fossil fuels emissions. Basically, most of the scenarios signal either lose-lose outcomes or potential trade-offs between water quality and climate mitigation if decisionmakers address each of the issues on their own.

Luckily, not all of the options are doom and gloom. According to one of the authors, Anna Michalak from Stanford University, “[i]t is entirely possible to fight climate change in ways that don’t have unintended consequences for water quality.” But for this to happen, “[w]e need an approach that takes multiple benefits into account in the planning process.”

This requires much more attentive planning and application of nexus approaches to cover multiple sustainability domains at once. Effective conservation efforts paired with improved land management, changes in lifestyles and deeper consideration of our impacts on nature can result in better outcomes for water quality and human health.