Map Critique: Mapping shadows

I’m interested in mapping rhythms of the city, especially those that are hidden or overlooked in some manner. With my artistic practice currently taking the form of mobile projections, I’ve been considering the rhythm of sunlight and shadow in New York City, and how the movement of these elements interacts with our buildings and infrastructure, influences our paths within space, determines the appeal of real estate, and generally creates a sense of place. I think about the privilege of natural light in a city like New York; how rising towers create stunning penthouse views and long, looming shadows over those below. I think about friends who’ve lived in “bedrooms” deemed illegal for their lack of window, and my own experience living in a lofted studio where the loft was so cave-like my circadian rhythm changed. I think about how it’s the shadows of the financial district that conjure feelings of walking the medieval streets of Siena, Italy, despite the stark contrast between architecture and age of the two locales.

This week’s lesson is on critical cartography. My search for a critical mapping of New York’s light and shadows wasn’t fruitful, but it did turn up this interactive map from The New York Times, which is what I’ve chosen for my critique. While my selection isn’t an example of critical cartography, I thought I could analyze it through the lens of critical cartography.

Mapping the Shadows of New York City: Every Building, Every Block was created as part of an online article on So it was either the basis for or at least essential to the article from the start. Living on The New York Times’ website, the map is a digital, web-based, interactive with control of the perspective zoom, layer view, and mouse-hover states. It takes a Godview perspective, so the zoom controls the height of the overhead perspective. You can select from seasonal layer view: winter, spring/fall, and summer. There are two hover states, which are only enabled once you’re zoomed in enough. When you hover over the street, you can view the amount of day spent in shadows across seasons. Hovering over buildings tells you the address or name of the building, in addition to its height in feet and its construction date.

So this map uses digital technology to create a layered experience that measures shadows against time in hours and minutes, season, and evolution of the city’s construction.


Here’s how the the team at Tandon School of Engineering at New York University calculated the shadows:

“To measure shadow coverage, they used a metric known as shadow accumulation, which is simply the total number of minutes that a given point spends in shadow over the course of a day. Point A is darker than Point B because it has been in shadow for one more minute. But Point C will accumulate the same amount of shadow as Point B, because it receives one minute of shadow from both Building 1 and Building 2.”

This process made me think of Annette Miae Kim’s Sidewalk City: Remapping Public Space in Ho Chi Minh City, in which she details her process of using ‘ghost map logic’ with transparent circles, and their increasing brightness with overlap, to “show space constructed by human activity.” In NYU’s case, this overlap method is used to generate the data, while Kim uses it in her representation of the data. Overall, I feel the NY Times’ presentation of the data makes sense in the context of journalism and current digital journalism trends, but this information could really benefit from the variety of representations that critical cartography supplies.

Mainly, I think we could humanize the data. NY Times presents a map that’s completely devoid of human presence except for the mouse interaction from the reader. What I see is 4 colors, 3 with gradation changes to show the seasonal shadows, a traditional gridded base map of streets and building outlines, from the Godview perspective, and I’m asked to care about what happens with my mouse hovers and clicks? Quite sterile and actually overwhelming in its monotonous presentation, even though I know there’s really cool information and implications unfolding in those shadows. This is where the context of journalism comes in and lends the human-centered focus with text: the written article sheds light on how this relates to human society, history, and economy — why we should care. In this way, I can see the fulfilling narrative power that Kim speaks to in Sidewalk City when addressing the image+text topic in mapping.

With my interpretation, I would humanize the data by putting the tools in the hands of the user, placing the user and the data in the space, so they can experience it at human scale. I would create a performative cartography experience where users go to shadowed locations with a portable projector in hand and control projections of the visualized data about that space in situ, experiencing how the changing light affects the image’s display. 

Users would be directed to specific locations to project visuals based on that location and its shadows. The visibility of the image would ebb and flow with the light of the day, season, and street activity. So you might be learning about when a building was erected by projecting this data on the building itself while shifting shadows of current construction cranes interrupt this experience, encouraging you to reflect on the rhythmic relationship between structure, shadow, and human in city life.

Key to this experience is that layering of light on shadow on city surface and the interplay that arises as a metaphor for the patchwork quilting of the city itself. I want people to consider spaces that are constantly or never in shadow, partially or intermittently shadowed, why their rhythms are so, who occupies these spaces, etc.