Monitoring Boundary Layer Inversions for Agricultural Practices

Boundary-layer inversions are a frequent evening condition in the Midwest that have significant implications on agricultural practices. Their occurrence inhibits mixing leading to stagnant and/or horizontally drifting air. For agricultural practices, these can lead to high ammonia concentrations, undesirable odors, and chemical drift that can negatively impact nearby, susceptible receptors. Chemical drift has attracted the most attention in the last few years in the region.

The process leading to inversion conditions is well known, but there is a very limited climatology at local scales about the occurrence, intensity, and duration of these events. Improved monitoring for inversions is necessary for agricultural producers to make better informed decisions when applying chemicals and managing manure operations.

The USDA Midwest Climate Hub recently provided inversion monitoring equipment to be installed at select observation sites across 6 states: Illinois, Indiana, Michigan, Missouri, Kentucky, and Ohio. Data from these and other observations around the region are being collected into a centralized location that offers standardized data access. This data portal provides near real-time monitoring of local inversions along with historical and forecasted inversion information. It also provides data access so additional research can occur to advance the knowledge of the climatology of inversions and be utilized for agricultural planning and practices. This regional monitoring of inversion conditions is a first of its kind on a regional basis in the country.