Semiarid regions have very similar characteristics to arid regions - which means that they are very dry - except for the fact that they are a little bit less dry. To give a more practical example: arid regions usually have an average of 10 inches of rain per year, while semiarid regions have an average of about 20 inches of rain per year. Both animals and plants have adapted to survive with little rain.
Both the Iranian Plateau and the Anatolian Peninsula share this same climate.
