Earth integrated housing includes underground housing but often opened up a bit to allow more windows. So some of the house is underground, many of the walls are surrounded by earth, but with more room for windows (often by excavating some earth to provide window views).
Obviously they provide good ability to maintain a more pleasant temperature when things get very cold or very warm.
Mike Oehler’s website on Underground Housing.
Related: Benefits of Green Roofs – Rustic Homestead Community – Monastery of Saint Simon (Cave Church), Cairo, Egypt – Wonderful Low Impact Woodland House