Nutrient Pollution Due to Climate Change-Induced Winter Warming Affects 40% of the US

Nutrient pollution is becoming a new threat in the contiguous US due to winter warming caused by climate change, according to a new study.

Its researchers show that nature is playing a role in melting hazardous chemical pollutants frozen in ice and bringing them to different bodies of water in the country. The pollution is mainly caused by average-normal temperatures during the winter season.

Despite the seemingly natural process, scientists have warned that human activities have aggravated the process of climate change and the greenhouse effect, which is responsible for the warming of the planet.

Recent studies have shown that the worst is yet to come by the end of the 21^st century unless concrete actions are made to mitigate greenhouse gas emissions and the burning of fossil fuels.

The Dangers of Nutrient Pollution

The new paper was published in the journal Environmental Research Letters made available on Wednesday, October 5. It has a research title about winter runoff events posing an unquantified continental scale risk of nutrient export during winter.

The paper was led by a team from the University of Vermont, the University of Colorado, the University of Kansas, and the University of Michigan.

In the study, scientists are raising the alarm regarding a significant new threat to US water quality. This comes as winters start to warm due to climate change, releasing large amounts of nutrient pollution into inland bodies of water like lakes, rivers, and streams.

The national study has been considered the first of its kind to be able to determine that previously frozen winter nutrient pollution, unlocked by rising winter temperatures and rainfall, is putting the water quality at risk in 40% of the contiguous US, which consists of over 40 states.

The risk comes from nutrient runoff into the bodies of water from phosphorus and nitrogen in fertilizers, manure, animal feed, and among others.

This has affected the country's water quality for decades. However, most research about nutrient runoff in snowy climates has gazed during the growing season.

In a historical perspective, cold temperatures and a continuous snowpack froze nutrients like nitrogen and phosphorous until the watershed thawed in the spring season, a period when plants could help absorb excess nutrients.

Winter Warming and Climate Change

Climate change-induced global warming has been attributed by scientists to be the cause of above-average temperatures even during the winter season, which spans in the US between December and February.

In the new research, the scientists found that "rain-on-snow" affects 53% of the contiguous US and puts 50% of the US nitrogen and phosphorus pools at risk of being shifted to groundwater and surface water. When these phenomena converge, over 40% of the contiguous US is at risk of nutrient export and soil loss from rain-on-snow events, as cited by Phys.org.

The study's research team is hoping that their work will serve as a wake-up call for government agencies and researchers, since it shows that 40% of the US is producing winter pollution.

Yet, no individual or group is tracking exactly its quantity, destination, or its impact on water quality and the wider ecosystems, according to Carol Adair, a researcher at the University of Vermont, as cited by Phys.org.