Stratus (song)

"Stratus" is an instrumental jazz fusion composition written by Polish keyboardist and composer Michał Urbaniak. It is widely recognized as one of the signature pieces of the jazz-rock band Weather Report, having been adapted and popularized by them on their 1974 album Mysterious Traveller.

The original Urbaniak composition, released on his 1973 album Fusion, features a more abstract and experimental sound. Weather Report's interpretation, however, is characterized by its driving, syncopated rhythm, prominent use of synthesizers, and the interplay between various melodic and harmonic elements.

The song is structured around a repeating bass ostinato, which provides a foundation for the other instruments to improvise and build upon. Key features of the Weather Report version include Joe Zawinul's signature use of the ARP 2600 synthesizer, particularly for the iconic "stratus cloud" sound effects, and Wayne Shorter's saxophone melodies. Alphonso Johnson's bass line and Ishmael Wilburn's drumming provide the track's powerful rhythmic drive.

"Stratus" is considered a classic example of jazz fusion, showcasing the genre's blend of jazz improvisation, rock instrumentation, and electronic soundscapes. Its influence can be heard in the work of many subsequent jazz and fusion musicians. The composition remains a popular performance piece and is frequently studied and analyzed by music scholars and enthusiasts.