Moray

Moray (Muray) is an archaeological site in Peru approximately 50 kilometres (31 mi) northwest of Cuzco on a high plateau at about 3,500 metres (11, 500 ft) and just west of the village of Maras. The site contains Inca ruins, mostly consisting of several terraced circular depressions, the largest of which is approximately 30 m (98 ft) deep. As with many other Inca sites, it also has an irrigation system. The purpose of these depressions is uncertain, but their depth, design, and orientation with respect to wind and sun creates a temperature difference of as much as 15 °C (25 °F) between the top and the bottom. Closed depressions such as these can trap cold air, particularly on calm cloudless nights at altitude. Heat in the form of long-wave radiation is free to escape skyward and cold air is heavier than warmer air, so it flows downslope. In most landscapes the cooler air drains into the valleys creating down-canyon winds at night and leaving the higher slopes a few degrees warmer. This pattern is called an inversion because the typical pattern of air cooling as elevation increases is inverted. If air can flow into a closed basin, the capture of cold air is accentuated. Warmer air is displaced from the basin leaving the cold air trapped under a stable inversion. Temperatures in the basins can be several degrees cooler than the surrounding lands and remain colder until st

Archaeological site data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).