The concept of ice fabric served as inspiration for one of the central pieces of Signal, a large-scale textile collage modeled after a working sail. Made from cyanotype prints on fabric, the sewn prints feature scientific figures, diagrams, declassified aerial photographs of Thwaites glacier, and experimental cyanotype prints made from glacial erratic boulders left behind by the Laurentide Ice Sheet in coastal Rhode Island, USA.
The textile collage references sails as tools of navigation and transport across bodies of water, flags as modes of remote communication and signifiers of cultural identity, and quilts as intimate, handmade memory-keepers. Using rope systems and rigging, this piece is installed differently in each space. The “sail” is tethered to the architectural features of the room, and can be tied to other objects like ceramic knots, found rocks and geologic material, glacier fieldwork equipment, and suspended ice-core-like sculptures, the latter of which slowly melt. The dripping sounds are amplified and projected back into the exhibition space. Observers witness the shifting tension within the rigged system, as the gradual change in ice mass subtly impacts the positioning of the other objects in space. As a whole, the installation invites a deeper awareness of the ways in which bodies and glaciers, respond to forces both seen and unseen, holding within them histories of strain, adaptation, and resilience.
A death rattle is the sounds a human body makes at the end of life when fluid enters the lungs. The sounds associated with this process and the parallels between human and ice bodies led to our work using seismic recordings of glacial calving events to compose a death rattle for Thwaites Glacier.
Calving events are triggered by the progressive growth of cracks and void space in the ice at the terminus of marine-terminating glaciers (Schulson, 1990; Vaughan, 1993; van der Veen, 1999).
To build this composition Andrew applied an automated “event picker” (Winberry et al., 2020) to identify calving events in broadband 3-component seismic data collected between 2009 and 2020 from a remote station anchored to the surface of Thwaites Glacier (76.45 S, 107.78 W).
For each event, the seismic recording was shifted to human-audible frequencies. Tyler then converted these timeseries to audio files and mixed them into compositions designed for live accompaniment with ringing bells, vocalizations, and amplified sounds of rocks in contact with one another.
In signal processing, coherence is a metric used to measure a relationship between two signals1 and can indicate similarity or causality. For example, we can get a measure how similar two voices are to one another, or whether ocean tides affect groundwater levels at a coastal farm. Coherence can also mean making sense (a coherent argument) and/or a complementary coming together of (coherent efforts).
In radar data collected from Thwaites Glacier, we compare two signals to each other to estimate the strength and orientation of the ice fabric2. The more similar they are, the weaker the fabric. The more different they are, the stronger the fabric.
While processing the coherence of these radar data, Elizabeth generated looping plots. Tyler composed choreographies inspired by them, and repeated the choreography multiple times. Elizabeth then analysed each still using an edge detection algorithm. Ultimately, these will be used to measure the “coherence” of Tyler’s repeated performances. We anticipate these will be performed repeatedly, that more choreographies will be produced, and that the subsequent performances will involve multiple dancers moving (in)coherently, as well as open workshops for public participants. For each of these, the signal processing will be performed in real time.
In radar data collected from Thwaites Glacier, we compare two signals to each other to estimate the strength and orientation of the ice fabric2. The more similar they are, the weaker the fabric. The more different they are, the stronger the fabric.
While processing the coherence of these radar data, Elizabeth generated looping plots. Tyler composed choreographies inspired by them, and repeated the choreography multiple times. Elizabeth then analysed each still using an edge detection algorithm. Ultimately, these will be used to measure the “coherence” of Tyler’s repeated performances. We anticipate these will be performed repeatedly, that more choreographies will be produced, and that the subsequent performances will involve multiple dancers moving (in)coherently, as well as open workshops for public participants. For each of these, the signal processing will be performed in real time.
[1] a signal is, generally, a function that conveys information about a phenomena. It can be a waveform, like a soundfile of a song, or measurements of the tide over the summer.
[2] ice fabric: glacial ice is made of lots of ice crystals shaped a bit like a hexagonal cylinder. the orientation of these ice crystals affects how fast ice flows, and also the speed at which electromagnetic waves travel through ice.