How do we conceptualize 'hot cities' and their inhabitation in a warming planet? Experiences of heat are dynamic: constantly at play with various political, socioeconomic, and ecological factors that result in a varied terrain of heat experiences, and subsequent techniques to stay cool. At Karachi Urban Lab, we understand that theorizing heat as such a phenomenon requires an exploratory approach and engagement with innovative research methods. Sensory research can be a powerful tool for encapsulating dynamic experiences of heat in the city, particularly through the use of soundscapes, supplemented with visual documentation (Pijanowski et al., 2011). How are heat and methods of cooling perceived through sensorial elements? How do they contribute to the acoustic fabric of the city? And how can this be used to understand the effects of the changing climate on lived experiences? Below, we discuss some samples from an ongoing collection of sound bites from both the open and the built environment, that are linked to heat and cooling in various spaces of Pakistan's largest metropolis, Karachi.
The first few selections are sounds from mechanical interventions that are meant for keeping spaces (mostly indoors) cool, while the remaining sounds are from open environments, especially from areas containing “natural shade” that are often occupied to avoid heat and its bodily impacts. Our experiences thus far have distinguished mechanical cooling by the overwhelmingly loud and persistent sounds that become the backdrop to most indoor spaces during summer heat. These sounds are mostly emitted from constantly running cooling technology such as fans and air conditioners.
Clips 1 and 2 - Sounds from air conditioning exhausts installed on a public university's rooftop and a ceiling fan in one of the rooms, respectively.
In commercial kitchens, for example, the fans and exhausts are in constant motion to keep the space ventilated. So much so, that the staff often step outside in the heat to get a breather and cool off. Within the kitchen, the workers have set up a “break corner” with a pedestal fan. The fan has a considerably lower volume as compared to the exhaust, creating space between the hot kitchen and the cooling area.
Clips 3, 4 and 5 - Sounds from various cooling equipment installed in the kitchen at a popular restaurant in the city’s centre
Built-in interventions often also exhibit repetitive patterns of sounds, such as what is observed in sounds produced by ceiling fans and garden sprinklers. The “ghan ghan ghan” sound of the fan motor is largely recognized and held as a reassurance of a wind source, irrespective of whether it has any real cooling impact or not. Similarly, the sprinkler’s distinct sound produced by every rotary motion forms a “rhythm of cooling”, as one begins to expect a hit of coolness from the misting effect of the sprinkler at regular intervals. Of course, these sprinklers are a distinct feature of privately maintained green/recreational spaces, and these sounds and motions are thus accessible to only certain sects of the population in Karachi.
Clips 6 and 7 - Sounds from cooling technologies that operate in repetitive motions, i.e., a ceiling fan and a garden sprinkler
Natural, shaded spaces, in contrast, offer very distinct sounds of their own. These are much less persistent, fluctuating in both their loudness and speed. Acoustics in outdoor spaces are thus less controlled, and are complicated by symphonies of biophonic, geophonic, and anthrophonic sounds. The size of the leaves, the location of the tree, and the density of its branches, for instance, all contribute to how the wind rustles, and often indicate various qualities of cooling. Birds and other inhabitants of natural shade also provide unique atmospheres and are proven to respond to varying temperatures and humidity through vocalizations (Keim, 2019).
Clips 8, 9 and 10 - Differences in atmospheric sounds based on winds, type of plantation, and biological inhabitants
Clips 8, 9 and 10 - Differences in atmospheric sounds based on winds, type of plantation, and biological inhabitants
Defining thermal experiences through sensory data such as sound opens up gateways to explore the variations in thermal experiences across the city, and lends itself to opportunities of further inquisition, as scientists have come forth with new conceptualizations on how climate change alters the acoustics of ecosystems and lived spaces (Sueur, Krause & Farina 2019). We use this as a jumping point to not only address the changing climatic landscape of Karachi, but also how it is perceived and adapted to in variation, thereby encouraging heat to be understood as much more than just a spike in temperature.
Keim, B., (2019). “What does climate change sound like?” Anthropocene | Innovation in the Human Age. Available at: https://www.anthropocenemagazine.org/2019/11/climate-change-biophony/
Pijanowski, B.C., Villanueva-Rivera, L.J., Dumyahn, S.L., Farina, A., Krause, B.L., Napoletano, B.M., Gage, S.H. and Pieretti, N., (2011). “Soundscape ecology: the science of sound in the landscape.” BioScience, 61(3), pp.203-216.
Sueur, J., Krause, B. and Farina, A., (2019). “Climate change is breaking Earth’s beat.” Trends in ecology & evolution, 34(11), pp.971-973.
This enquiry is part of a larger project, Cool Infrastructures: Life with Heat in the Off-grid City, funded by the United Kingdom's Global Challenges Research Fund (GCRF). The project focuses on access to cooling through human-infrastructure interactions amidst rising temperatures in four cities: Hyderabad (India), Yaoundé (Cameroon), Jakarta (Indonesia) and Karachi (Pakistan) -where research is being led by the Karachi Urban Lab - a research center based at a public sector university, the Institute of Business Administration (IBA).
