Lake Turkana ( /tɜrˈkɑːnə/ or /tɜrˈkænə/), formerly known as Lake Rudolf, is a lake in the Kenyan Rift Valley, with its far northern end crossing into Ethiopia. It is the world's largest permanent desert lake and the world's largest alkaline lake. By volume it is the world's third-largest salt lake^{[citation needed]} after the Caspian Sea and Issyk-Kul (passing the shrinking South Aral Sea), and among all lakes it ranks twenty-fourth. The water is potable but not palatable. It supports a rich lacustrine wildlife. The climate is hot and very dry.