Irradiated Shade

The paper details computational mapping and modeling techniques from an ongoing design research project titled Irradiated Shade, which endeavors to develop and calibrate a computational toolset to uncover, represent, and design for the unseen dangers of ultraviolet radiation, a growing yet underexplored threat to cities, buildings, and the bodies that inhabit them. While increased shade in public spaces has been advocated as a strategy for “mitigation [of] climate change” (Kapelos and Patterson 2014), it is not a panacea to the threat. Even in apparent shade, the body is still exposed to harmful, ambient, or “scattered” UVB radiation. The study region is a binational metroplex, a territory in which significant atmospheric pollution and the effects of climate change (reduced cloud cover and more “still days” of stagnant air) amplify the “scatter” of ultraviolet wavelengths and UV exposure within shade, which exacerbates urban conditions of shade as an “index of inequality” (Bloch 2019) and threatens public health. Exposure to indirect radiation correlates to the amount of sky visible from the position of an observer (Gies and Mackay 2004). The overall size of a shade structure, as well as the design of openings along its sides, can greatly impact the UV protection factor (UPF) (Turnbull and Parisi 2005). Shade, therefore, is more complex than ubiquitous urban and architectural “sun” and “shadow studies” are capable of representing, as such analyses flatten the three-dimensional nature of radiation exposure and are “blind” to the ultraviolet spectrum. “Safe shade” is contingent on the nuances of the surrounding built environment, and designers must be empowered to observe and respond to a wider context than current representational tools allow.