January 11, 2008
Perth is the capital of Western Australia and the largest city in the southwest of the continent, with an estimated population of over 1.5 million (as of December 2006). Perth's city center and surrounding suburbs lie on the floodplains of the Swan and Canning Rivers, which flow through the center of the city. Perth has a Mediterranean climate, with hot and dry summers and cool and humid winters. Wildfires can occur during the summer; several large fires threatened the eastern part of the metropolitan area in 2005.
This astronaut photo captures changes in urban land cover around Perth. The city center (pictured left) is characterized by large buildings (such as skyscrapers) with white reflective roofs. The southern suburbs (across the Swan River) are characterized by a higher density of small buildings and predominantly red-purple roofs. Several areas of green vegetation are visible in the image. The park and golf course consist mostly of grassy areas, which are uniformly green, while the dense canopy of Kings Park is a darker green. The changing colors of the Swan and Canning rivers are due to sunlight, or light reflecting off the water's surface, which acts like a mirror and is reflected directly back into the footage of the astronauts on the International Space Station.
