Alpine glaciers are formed on the sides of mountains and push their way through valleys, while ice sheets cover broader spaces, including valleys, plains and mountains. This second type of glacier primarily exists in Antarctica and Greenland (National Geographic).
The glaciers I saw in Patagonia are classified as Alpine Glaciers. At higher altitudes, where the air is colder, these glaciers survive year round. My friend and I were in Patagonia in February (during the peak of summer), and it was only around 40 degrees Fahrenheit at night at our campsites at low altitude. This means that it was notably colder at altitudes where the glaciers are located. However, even further up north in Chile near Santiago, where the climate is significantly warmer, it is still possible to see glaciers from the city, high above in the Andes. Nested within mountains with elevations over 16,000 ft, glaciers in the Andes have thrived for 12,000 years (COHA).
Even in the very northern desert in Chile, you can find snow-capped mountains. A couple years ago, when I was in the Atacama desert in the very northern portion of Chile, I hiked a volcano up to about 18,000 feet. There was even snow located on the top of the volcano in the middle of the driest desert on earth! However, the difference here is that the snow on the volcano is not considered to be glacial because it comes and goes with the seasons.
Sources: United States Geological Survey (USGS). https://www.usgs.gov/faqs/where-are-earth-s-glaciers-located, National Geographic. https://www.nationalgeographic.org/encyclopedia/glacier/, Council on Hemispheric Affairs (COHA).http://www.coha.org/the-andean-glaciers-from-12000-years-ago-to-today-2/
