A Hazy, Foggy Day in Italy’s Po Valley

Typography

The Po River Valley, one of Italy’s most densely populated regions, is home to over 16 million people. The valley is also one of the country’s foggiest and haziest regions.

The Po River Valley, one of Italy’s most densely populated regions, is home to over 16 million people. The valley is also one of the country’s foggiest and haziest regions.

In the fall and winter months, fog and low clouds routinely blanket the basin, often preceded by haze—a mixture of airborne particles, known as aerosols, emitted by vehicles, fires, industry, and other sources. The surrounding mountain ranges limit air circulation, helping fuel temperature inversions that trap air pollution near the surface.

The MODIS (Moderate Resolution Imaging Spectroradiometer) on NASA’s Terra satellite captured this image of morning fog on November 16, 2024. “It formed when a high-pressure system over central Europe led to calm and stable conditions in the valley, ideal for the formation of radiation fog,” said Eva Pauli, a research meteorologist at the Karlsruhe Institute of Technology in Germany.

Read More: NASA Earth Observatory

Photo Credit: Wanmei Liang, using MODIS data from NASA EOSDIS LANCE and GIBS/Worldview