Background ozone a major issue in US West
Wednesday, September 30, 2015 - 06:00
in Earth & Climate
Levels of "background ozone"—ozone pollution present in a region but not originating from local, human-produced sources—are high enough in Northern California and Nevada that they leave little room for local ozone production under proposed stricter U.S. ground-level ozone standards, finds a new NASA-led study.