Black carbon distribution. Computer visualisation showing the atmospheric concentration of black carbon across the globe. Black carbon is the tiny air pollution particles commonly known as soot. It enters the air when fossil fuels such as coal are burned. Since black carbon readily absorbs heat from sunlight, the particles can affect Earth's temperature and weather. Here the concentration is colour-coded based on how much light is absorbed in each area (see bar at lower left). This image was created using satellite data gathered between August and November 2009.