Karoo Ice Age Karoo Ice Age The Karoo Ice Age, more commonly referred to as the Late Paleozoic Ice Age, from 360–260 million years ago (Mya) was the second major ice age of the Phanerozoic Eon. It is named after the tillite (Dwyka Group) found in the Karoo Basin of South Africa, where evidence for this ice age was first clearly identified in the 19th century. The tectonic assembly of the continents of Euramerica (later with the Uralian orogeny, into Laurasia) and Gondwana into Pangaea, in the Hercynian-Alleghany Orogeny, made a major continental land mass within the Antarctic region, and the closure of
Semi-arid climate Semi-arid climate A semi-arid climate or steppe climate is the climate of a region that receives precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-arid climates, depending on variables such as temperature, and they give rise to different biomes. A more precise definition is given by the Köppen climate classification, which treats steppe climates ("BSk" and "BSh") as intermediates between desert climates (BW) and humid climates in ecological characteristics and agricultural potential. Semi-arid climates tend to support short or scrubby vegetation and are usually dominated by either grasses or shrubs. To