New research from the University of Minnesota, published in Proceedings of the National Academy of Sciences, shows nitrous oxide emissions, a greenhouse gas, may get worse as the climate warms.
While not as prevalent in the atmosphere as carbon dioxide, a nitrous oxide molecule is nearly 300 times more effective in terms of warming the planet.
The University of Minnesota’s Biometeorology Group, including Drs. Tim Griffis, John Baker, Dylan Millet, Rodney Venterea and Ph.D. student Zichong Chen, studied the atmosphere and nitrous oxide emissions from a tower 200 meters in the air in Minnesota. The gas comes from many sources, including emissions from farm fields and associated runoff. For six years they recoded the nitrous oxide levels every hour. The highest levels were recorded during the warmest years. In 2012, the warmest year of the study, emissions were nearly 50 percent higher.
Current models do a relatively good job of estimating nitrous oxide emissions from direct sources, like fertilizer application to fields. The team’s research found that indirect emissions from streams and ditches were also a large source that showed significant seasonal and internal variability. Using long-term measurements and modeling, they suggest that emissions will increase significantly as temperature and precipitation increase.
Continue reading at University of Minnesota
Image via University of Minnesota