Asia is the largest continent and has the longest coastline of all the continents. Asia has a total area of approximately 17.2 million square miles and a coastline stretching 39,022 miles. Asia is bordered by the Pacific Ocean, the Indian Ocean and the Arctic Ocean.
Asia is divided into 48 countries. The continent's population of 4.3 billion people makes up 60 percent of the world's human population. Asia's population catapulted during the 20th century with a quadruple increase. Asia has diverse climates ranging from arctic and subarctic in Siberia to tropical climates in Southeast Asia and southern India. The area with the most activity worldwide for tropical cyclones is within Asia, south of Japan.