The Art of Weather

Campbell Scientific have an embedded culture of supporting fresh thinking in science and this year our UK sister company CSL were proud sponsors of a ground-breaking installation that brought science directly into the realm on the arts.


The Variable 4 project uses changing weather conditions, measured by a Campbell Scientific weather station, to create a unique musical experience which was performed as a 24 hour installation piece on Dungeness Headland in Kent on May 22nd. Here is how Daniel Jones, one of the projects composers, describes the event:


“Variable 4 transforms weather patterns into a living musical composition with the same instability and unpredictability as the elements themselves. Using meteorological sensors connected to a custom software environment we have developed, the wild weather conditions of the Kent coast-land are used to generate new combinations of musical forms, heard through a field of speakers embedded invisibly into the landscape.”


Variable 4 takes live weather data from the environment using a research-grade weather station, Campbell Scientific’s BWS-200. This information, updated every few seconds, is used to drive a web of compositional processes which result in a dynamic composition which responds in real-time to the current atmospheric conditions.


At the core of this process is a piece of software which plays the role of conductor, navigating across a map of movements which correspond to potential combinations of weather. This motion takes place over the course of minutes and hours.

On a more fine-grained level, each movement itself comprises of score fragments and compositional processes, which are altered and recombined by second-to-second changes in the surrounding weather.
Finally, the combined output of these musical elements is diffused over an arrangement of 8 speakers by a spatialisation component, itself also determined by weather data.

Score.

The hexagonal lattice below maps out the 24 movements that make up Variable 4. Each hexagonal tile represents a movement, corresponding to a set of weather conditions: temperature, humidity, wind speed, solar radiation and rainfall. As the piece plays, its position can always be located on this map, constantly shifting between movements according to the changing atmosphere.

Each movement also has a key signature, tempo and metre, determined by its related weather state. These are spatially linked according to the circle of fifths (and circle of fourths), a musical relationship common within Western music, making it possible to move between movements without harmonic dissonance. Try moving diagonally north-east from any movement, wrapping from top to bottom, and you will see that you continue to move upwards in key by one fifth per tile.

If the weather changes so quickly that the location is caused to jump between distant movements, the piece enters what we term a ‘wormhole’: an arrhythmical and often atonal bridge, which serves to join two unrelated musical elements.

Algorithms

Alongside the precomposed parts of each movement are compositional processes, or algorithms: sets of instructions which encode musical behaviours, capable of recombining existing material and generating entirely new sequences of notes. These serve to massively increase the scope of potential patterns produced by Variable 4, and enable us to respond closely to the finer details of the meteorological conditions.

On a movement-wide level, chance procedures are used to move between fragments according to sets of relationships designed at the compositional stage. The dynamic recombinations of these parts generate polyrhythms and composite tonal structures.

At the level of individual notes, a second set of algorithms are used to compose original note patterns. With structures drawn from mathematics, statistics and biology (above), these can continually produce sequences that are surprising even to the composers.

Variable 4 is comprised of 24 musical movements, each of which contains scored, recorded and programmed elements. Every movement also corresponds to a set of meteorological conditions:

• temperature
• rainfall 
• wind speed 
• humidity 
• sunshine hours 

If the current weather conditions correspond to a given movement, the piece will gradually begin to transition towards this movement.

On top of this piece-scale layer, multiple elements are operating over shorter timescales which respond to more immedate weather conditions (wind direction, short-time wind speed, solar radiation) to give finer details. These, too, are related to each movement.

The movements are numbered following the Circle of Fifths, and subtitled according to Italian tempo or expression markings which best describe their mood.

Wormholes

In the context of this piece, a ‘wormhole’ is an arrhythmical and often atonal bridge, which serves to join two unrelated musical movements. There are six wormholes within the piece, derived from a broad range of source material. Each wormhole is algorithmically manipulated by the current weather conditions on a variety of different levels.

More details can be found at www.variable4.org.uk or by following the project’s Twitter
page at http://twitter.com/variable4

Article Reprint Courtesy of CSL