This is from a model simulation of carbon monoxide, a pollutant usually present with black carbon in the atmosphere, in the middle and upper troposphere in March-April 2010. Intercontinental transport of pollution eastward across the Pacific occurs in association with a dry circulation (clockwise) in the central Pacific in springtime. Black carbon can travel longer distances across the Pacific between Asia and North America during this period, leading to higher black carbon loadings in the Northern Hemisphere. The Real-time Air Quality Modeling System (RAQMS) provided these global air quality forecasts in support of the NOAA CalNex field mission, which followed HIPPO 3 during May and June, 2010.
Credit: Animations courtesy of R. Bradley Pierce, NOAA/NESDIS/STAR