Mountains and winds confound particle distribution
Untangling complex relationships requires understanding and facts. Applying both, Pacific Northwest National Laboratory led research finding the true culprits instigating layers of tiny atmospheric particles above California's central valley. Contrary to previous assumptions, local recirculation patterns, affected by winds interacting with the unique topography of the Sierra Nevada Mountains, create these particle layers. Global model simulations had incorrectly tied the layers to a mix of long-range transport of pollution from Asia and local emissions of soot and particles from burning fossil fuels. This research improves understanding of how the particles impact the regional climate and policy makers' decisions on how to regulate these emissions.