ABSTRACT
The sole criterion of the desert climate is aridity, but aridity in its turn produces a number of secondary characteristics such as sunshine, temperature range and even relief and soil types which help to conjoin deserts into a single climatic group wherever and for whatever reason they occur. The chilling influence of the currents has a profound effect on the climate of a somewhat narrow coastal strip. The coastal strips just described are only narrow fringes and grade rapidly eastwards into the true hot deserts, the climate becoming more and more extreme into the heart of the continent. The individuality of the desert environment is made up of a subtle mixture of climate and relief, but the relief of arid lands presents such a consistent and peculiar association of forms that it might almost be considered as an element of the climate.
