For more than a decade, scientists have observed ship tracks in natural-color satellite imagery. Now they can see that ships also have a more subtle, almost invisible signature.
Data from the Dutch and Finnish-built Ozone Monitoring Instrument (OMI) on NASA's Aura satellite show long tracks of elevated nitrogen dioxide (NO2) levels along certain shipping routes. NO2 is among a group of highly reactive oxides of nitrogen known as NOx that can lead to the production of fine particles and ozone that damage the human cardiovascular and respiratory systems. Combustion engines, such as those that propel ships and motor vehicles, are a major source of NO2 pollution.
Image courtesy of NASA”Aura Project Science Office.