The WeatherPlayer software is written in the Supercollider audio programming environment (www.audiosynth.com). The program creates generative music, which is controlled in various ways by 4 channels of MIDI input from the sensors. There are 16 generative compostions (i.e. music which generates itself using pre-defined algorithms) which are selected between by the light sensor, so each section is played as the sun rises, and then it steps through them backwards as the sun goes down. The temperature sensor has overall control over various parameters inside individual sounds, and also the length of the reverb trail. The wind sensor is used to control various parameters within many of the sounds in the composition. Finally, the water sensor activates synthesised water sounds, and controls the density of the drops.