Fire Band (IMAGE) Columbia Climate School Caption A dark blue band spanning north equatorial Africa shows where November-February density of polluting airborne nitrogen oxides have been declining. (Lighter blue areas to the south show lesser declines, but these are due more to to phaseouts of coal-burning power plants.) Yellow and red areas show increases in nitrogen oxides. Credit Adapted from Hickman et al., PNAS 2021 Usage Restrictions Credit must be given. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.