The European Space Agency released images today made by its Sentinel-5P satellite that show high concentrations of nitrogen dioxide in parts of Europe on November 22.
Nitrogen dioxide is mainly caused by vehicle emissions and in industrial processes.
Another image shows high levels of carbon monoxide, commonly produce by fires, in Asia, Africa and South America.
A series of images also show sulfur dioxide, ash and smoke from the Mount Agung volcano in Bali last month.