View all of the Arctic Hemisphere daily maps of total ozone for July 2017. Satellite instruments monitor the ozone layer, and we use their data to create the images that depict the amount of ozone. Click any map image to bring up a new page with a high-resolution map. Missing areas (bad orbits and polar night) are filled from an atmospheric model. The GEOS-5 FP data are produced by the Goddard Earth Observing System Model, Version 5. This is a system of models integrated using the Earth System Modeling Framework (ESMF). The GEOS-5 DAS integrates the GEOS-5 AGCM with the Gridpoint Statistical Interpolation (GSI) atmospheric analysis developed jointly with NOAA/NCEP/EMC. A week begins with Sunday. Fainter images are shown in the previous and following months. Missing days are indicated with a plain gray globe. Monthly averages (1979–2016)