EarthView–Rare Snow Falls at the Edge of Sahara Desert

Release Date: January 5, 2017

Last month, the Sahara saw a rarity: snow!

EarthViews is a continuing series in which we share a USGS Image of the Week featuring the USGS/NASA Landsat program. From the artistry of Earth imagery to natural and human-caused land change over time, check back every Friday to finish your week with a visual flourish!

This Landsat 7 image shows an area on the edge of the Sahara Desert in northwestern Africa after significant snow fell. Credit: USGS/NASA Landsat program.(Public domain.)

The EarthView: Rare Snow Falls at the Edge of Sahara Desert

Description:

In mid-December 2016, a rarity occurred on the edge of the Sahara Desert in northwest Africa. It snowed.

Landsat 7’s Enhanced Thematic Mapper Plus (ETM+) sensor captured the image that shows the white covering on the caramel-colored landscape southwest of the Algerian community of Ain Sefra, a town sometimes referred to as “the gateway to the desert.” All the snow except that at the highest elevations melted soon after, a fact Landsat 8 confirmed when it passed overhead on December 27.

A satellite image of snowfall in the desert

This Landsat 8 image shows the same area a few days later after most of the snow has melted. Credit: USGS/NASA Landsat program.(Public domain.)

Ain Sefra’s last snowfall occurred on February 18, 1979. While snow does collect in Africa at higher elevations—Mount Kilimanjaro in Tanzania has long been crowned by a cap of snow and ice—snow on the edge of the Sahara Desert seldom falls.

The average summertime temperature at Ain Sefra is 99 degrees Fahrenheit. Though winter temperatures are known to drop into the 30s, snow is as rare as the cool temperatures given that just a few centimeters of precipitation fall there annually.

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