On October 30, 2016, the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite flew over southern Europe and acquired this fantastic image.
The image focuses on Northern Italy and the Mediterranean Sea. Two large, green islands sit in the blue waters of the Mediterranean Sea. Although neighboring, the islands belong to two different countries. The largest island is Sardegna (Sardinia), Italy, while the smaller is Corsica, France.
The snow-covered Alps run from west to east across the northern section of the image, extending more about 750 miles. Eight countries share this mountainous terrain, including Monaco, France, Switzerland, Liechtenstein, Austria, Germany, Slovenia and, to the south, Italy.
Fog and haze hang in Italy’s Po River Valley south of the Alps. In cool weather early morning fog often collects in the Po River Valley. Fog typically appears bright white in MODIS images and often forms relatively large banks. Smog or haze, generally appears gray or blue-gray and often appears thinner and more veil-like.
The Po Valley contains the highest population density in Italy and produces significant amounts of pollutants from human activities. In fall and winter, temperature inversions often trap fog and pollutants near the surface of this valley.