Final answer:
The climate with 18 degrees Celsius, dry winters, and wet summers is known as a mediterranean climate and is classified as Type C climate or specifically as Csb (Warm-summer Mediterranean) or Csa (Hot-summer Mediterranean) in the Köppen system.
Step-by-step explanation:
The climate characterized by dry winters and wet summers with an average temperature of 18 degrees Celsius is typically a mediterranean climate. Places like Tasmania, Victoria, and regions in southeastern Australia, which have moderate and temperate Type C climates, fit this description. Major cities like Sydney, Melbourne, and Adelaide are situated in this climate zone, which is conducive to having a significant population due to its mild winters and warm, not excessively hot, summers.
The Köppen climate classification system can be used to identify this climate type more specifically. Under the Köppen system, climates with warm to hot summers and mild, rainy winters are typically designated as Csb (Warm-summer Mediterranean) or Csa (Hot-summer Mediterranean), depending on the summer temperatures.