A "Terra-Dome" Home is a specific type of Earth-sheltered Concrete Dome Home, designed by The Terra-Dome corporation in Missourri, USA. Their web page indicates they've been doing this since 1979. Their page is at www.terra-dome.com

Elevation: About 3500 feet (about 1.066 KM) This means the temperatures are a little cooler than Tucson (about 2427-2584 feet) and Phoenix (1092 feet).