Mapping for Resilience: Extreme Heat Deaths and Mobile Homes in Arizona

Abstract

YouthMappers help discover hidden vulnerabilities to extreme heat in the face of a changing climate by mapping health outcomes compared to energy assistance. What emerged is a pattern of disproportionate deaths by housing type, necessitating innovations in tagging unique mobile home attributes in OpenStreetMap (OSM). The resulting community engagement generated solutions that stakeholders and residents of mobile homes can implement for greater resilience, and a model for connecting SDG 13 (Sustainable Development Goals) for climate action to SDG 3 good health and well-being by looking at the homes where people live.

1 Local Impacts from a Global Problem

In an era where youth are demanding global climate action, there is a profound need to use local microdata in local places to better understand the impacts of climate change in our towns and neighborhoods. Data gathering is one way the youth can contribute to SDG 13, climate action. Such impacts include how climate change is affecting our health and well-being, which implicates the added opportunity to contribute as well to SDG 3, healthy communities. By creating local microdata in new ways, we can uncover some of the missing insights about what is happening, and show where vulnerable people are falling between the gaps. YouthMappers at Arizona State, who include international students who come from around the world to study geography and urban planning, have contributed to a discovery of hidden health vulnerabilities to the climate in places we live and work in the Southwest United States. Our connections link the global and the local in unexpected ways.

The most surprising fact that we learned through mapping locally about global problems is that local people’s health is impacted by climate heat extremes in different ways, depending on their housing shelter characteristics. Namely, our team’s research uncovered that although only 5% of housing in Maricopa County, Arizona, is in a particular kind of low-cost housing called mobile homes, approximately 30% of indoor heat-related deaths occur in these types of homes. Mobile homes are typically constructed with lightweight building materials and can be manufactured elsewhere and moved to lots (where they often become immobile over time). These parking areas are sometimes referred to as trailer parks and can include homes on wheels known as Recreational Vehicles (RVs). Often people from other parts of the country migrate from cold weather during the milder local winter months.

Especially the older mobile homes, which were built with lower energy standards as well as RVs that are not fully heat-ready, represent options that are affordable to struggling families or the elderly, but they do not withstand well during the Arizona summers, that are growing increasingly hotter each year. Thus, the residents of mobile homes in Maricopa County, Arizona are disproportionately affected by heat (Fig. 21.1).

Fig. 21.1

People who live in Recreational Vehicles (RVs) or mobile homes like these in Mesa, Arizona, are disproportionately exposed to extreme heat and suffer heat-related illness and death at rates up to six times higher than similar residents in other types of housing

Mobile home residents are vulnerable specifically because they are extremely exposed to heat due to the high density of mobile home parks, poor construction of dwellings, lack of vegetation (and thus lack of shade trees), socio-demographic features, and not being eligible to get utility and financial assistance. According to the Centers for Disease Control and Prevention (CDC), more people die in the United States from heat than from all other natural disasters combined. According to the Environmental Protection Agency (EPA), more than 1,300 deaths per year in the United States are due to extreme heat. Arizona, California, and Texas are the three states with the highest burden, accounting for 43% of all heat-related deaths.

2 YouthMappers Making Vulnerability Visible on the Map

During the summer of 2019, the YouthMappers at ASU hosted a series of collaborative mapping exercises in-person and online. Collectively as Arizona State University (ASU) students working as interns and research assistants in the research unit called, Knowledge Exchange Resilience (KER), we contributed our efforts in developing mapping data specifically for Recreational Vehicle (RV) and mobile home units across a number of trailer parks in Mesa, Arizona, east of our campus. This effort was launched to advocate for the gap in mapping data displaying RV and mobile homes as primary residences for long-term tenants within urban mobile home parks. Normally these areas on the map are not even marked for internal roads and typically not buildings, as they represent a neighborhood of privately owned property where lots are rented to mobile homes and RVs as tenants who own their unit but not the land beneath it. Our area of focus specifically marks spaces that were identified with a higher frequency of mortality rate resulting from heat-related death and illnesses.

2.1 Extreme Heat Deaths

In the summer of 2019, we requested and received data from the Maricopa County Public Health Department broken out by trailer parks versus all morbidity cases that happened indoors. They reported that year, 25% of all indoor heat deaths occurred in mobile homes, but in some years that rate reached as high as 40% (MCPHD 2006–2020). The data provided by the public health department was overlaid with other data we collected from organizations that provided utility assistance in form of various payment options. These utility assistance programs serve primarily low-income household residents occupying single-family homes and apartments, in the form of funding to offset the cost of electricity to run air conditioning. These services are provided through the local utility companies including Salt River Project power and water (SRP) and Arizona Public Service Electricity (APS). However, RV and mobile home dwellers are rarely ever eligible for the forms of utility assistance programs at that time, due to various policies implemented by the utility companies and certain federal (national US) guidelines.

2.2 Mapping the Pattern Beyond Indicators

The KER team began to analyze the provided data through GIS mapping and identified a pattern of hot spots of areas of indoor heat-related deaths. When compared to where utility assistance was provided, there were new patterns to analyze with stakeholders to triage where there might be a higher frequency of heat-related deaths with limited or no utility assistance recipients.

Phillips et al. (2021) recount our process of data acquisition and meaning-making that unfolded in our community geography research setting. The major discovery from this process was the extent to which people who reside in mobile homes were disproportionately at risk (MCPHD 2020). Many of the stakeholder organizations that provide support to people suffering health issues due to extreme heat were well aware of individual vulnerabilities like age or household income vulnerabilities. On the whole, this stakeholder community also utilized indicators, tracking county-level statistics through a Social Vulnerability Index. However, the spatial analysis done prior to KER and YouthMappers had not yet revealed the danger that the housing type implied (Wang et al. 2021). We pointed out that the SVI was missing any variables related to housing at all (Varfalameyeva 2020).

2.3 Gathering Data on Unseen Climate Vulnerable Locations

There are 92,031 mobile homes in Maricopa County, which is 5.2% of the total housing stock. These homes are located in approximately 686 mobile home parks spread throughout different parts of the urban core of Maricopa County, usually on the outskirts or in less valuable areas.

Our targeted area for mapping coincided with the densest location of heat-associated deaths where little to no assistance was being provided, namely in the stretch of surrounding mobile home parks located along Main Street in Mesa, Arizona. The satellite image below displays a wave of white and silver metal roofs reflecting from mobile homes and RVs. We highlighted the area of interest in red. It was very alarming to see the overwhelming density of mobile homes and RVs expanding along Main Street, which are typically hidden from street view, and are not represented on most maps because they are private property (Fig. 21.2).

Fig. 21.2

The concentration of trailer parks in Mesa, Arizona is visible on satellite imagery due to the reflection from metal roofs, paved lots, and a lack of trees (Google 2021)

Typically, mobile home parks in the US have an owner and landlord that manages these private development properties. As a result, mobile home building footprints or lots are not commonly identified on maps. The unique challenge of this matter required a mapping platform allowing local advocacy and access – but also global visibility. We utilized OpenStreetMap (OSM), which is an online open-source mapping engine that enables mapping by looking at satellite imagery as well as mapping using local tools and information. This allows local to global access in obtaining or generating maps to communicate local knowledge.

2.4 Labeling Attributes – The Challenge of a Novel Housing Type

The mobile home parks in this area, were not identified and labeled within OpenStreetMap, let alone each mobile home lot, so we as students and YouthMappers co-created mapping data identifying each park, and then each location for mobile homes and RVs. Co-generating and sharing our research efforts on the mobile home parks were key in our mapping data so they could be validated by other students, verified with city and county property data, and interpreted with community residents in order to generate solutions that make their homes more resilient to extreme heat.

We soon identified the lack of available categories, legends or labeling, that were adequate for identifying RVs and mobile homes as primary homes within OpenStreetMap. We wanted to create mapping data to specifically tag to identify long-term mobile home and RV dwellers in mobile home parks. However, OpenStreetMap was limited to labeling mobile homes and RVs as recreational units only. This definition does not fit the local circumstances well.

The challenges we experienced are utilizing the existing tags (labels) in OpenStreetMap identifying RVs as “tourism=caravan_site” which is fitting for tourist RVs but not for permanent living like for mobile homes. The tourism label also can be mistaken when people who migrate annually for the winter months consider themselves as residents, not tourists or even visitors (Varfalameyeva 2021).

After careful consideration, and consultation with knowledgeable people from the broader OSM community, we decided to utilize the tag “building=static_caravan” to label permanent living RVs, (which again are not the same as people who use RVs for travel or vacation). The mobile home tags were labeled as “A mobile home semi-permanently left on a single site” (Varfalameyeva 2021). Developing two specific tags would allow us to develop a data set that distinguishes the built environment within mobile home parks. This will tie later into the specific distinct solutions sets for making these dwellings more heat resilient. We can better manage the data and specifically identify the qualities of the two dwellings during our mapping process from the start. The static_caravan tag begins to characterizes semi-permanent mobile homes positioned on lots (Fig. 21.3). (OpenStreetMap 2021) This tag is our mapping method and tool to apply to a long-term mobile home unit (Fig. 21.3).

Fig. 21.3

Because of the unusual housing type, YouthMappers at ASU developed a special tagging convention for the project to identify these building features on OpenStreetMap

2.5 Results of Data Collection Campaigns

The image below is a real-time OpenStreetMap displaying our collaborative mapping data efforts in the red box which lists the contributors #YouthMappers, #HeatMappers, #ArizonaState, and #teachosm-project-834. We feel a sense of accomplishment about the amount of mobile home and RV data our team has been able to create and share with the community. The research focus area display blue polygons, polylines, and points on the map it describes the mobile homes positioned on the lots within the mobile home parks. This data has become a fundamental feature of ongoing research in ways that improve our ability to analyze and solve for heat. As a visual layer, we are able to utilize this OSM layer in ArcGIS Online as a basemap, which is useful for everything from presentations with community members to share quick analysis of overlap with other layers that may relate to social vulnerability (such as factors in the SVI). We can also tally units, calculate roof versus impervious surface space, and import real data into landscape design projects to seek how to optimize shade. These have been the foundational data for theses and student honors projects, as well as for visualizations informing local and national press articles. This particular collaborative mapping generation is serving as a beneficial pilot experience for our team members’ future academic research focus on rural Indigenous communities (United States) sharing similar gaps of limited mapping data. Other research questions are to look at the dynamics of geospatial climates of indoor versus outdoor temperatures in mobile homes and RVs within existing landscapes, from vegetation to limited or no vegetation, to test the effects of possible solutions (Fig. 21.4).

Fig. 21.4

Density of mobile homes are clearly visible on OSM after the project

3 Community Implementation with YouthMappers

There is an urgency of representation and communicating local knowledge, especially in the context of global conversations that may seem distant or remote. Mapping data allows our team to communicate the scales and impact of heat-related deaths within the focus area and have dialogue about how climate change is impacting Maricopa County residents. ASU students and YouthMappers emerge as the global citizens who are able to identify and learn about these communities through collective mapping generation efforts intersecting climate action. We think our efforts of advocating for mobile home park residents can impact future adaptation or remediation within local development, and become a model for resiliency planning. In addition, advocating affordable housing and immediate shelter resources to mitigate the impacts of extreme heat (Holmes 2021; Kear et al. 2020; Kutz 2020; Leahy 2020; Peterson 2021) (Fig. 21.5).

Fig. 21.5

The basemap display vulnerability scales, specifically mobile home dwellers. OpenStreetMap is an open mapping platform that provide access for our team to inform ongoing research solutions, climate change mitigation

3.1 Global Partners, Local Stakeholders, and Mobile Home Residents

YouthMappers collaborative mapping exercises have been a wonderful experience and we (ASU students) have developed a lot of applied methods for our own academic studies. Most of our research is advocacy through the agency of community and local knowledge, including local residents of parks, and with the county-wide organizations that serve and support them. We enjoyed the real-time web interactions with global collaborators and student chapter members during the live YouthMappers collaborative exercises and varying remote campaigns. Many of the ASU students had never participated in a real-time global hands-on mapping workshop and this was an exciting learning experience. The events were successful and the generated mapping data continues to serve the mobile home communities, the KER research team, and the Maricopa County Public Health Department as well as others.

The Mesa mobile home parks mapping data continues to be developed further in various quantitative data and attributes specifically, communicating ground truth for new questions or providing deeper understandings of on-going issues. Our co-generation data efforts helped us present the vast density of urban mobile home developments in Maricopa County. The mapping exercises developed tangible data for mobile home residents and local leaders to participate in spaces and conversations about problem solving.  

3.2 Toward Heat Resilient Solutions

The most motivating outcome of this work has been to co-develop heat solutions with residents and local stakeholders. Through months-long series of meetings convened by KER in 2020 and 2021, we researched numerous solutions across different domains that could help build the heat resilience of mobile home residents. As a result, we generated 50 heat mitigation solutions for mobile home residents, at various budget levels and depending on locally available resources (Varfalameyeva et al. 2021). The 50 solution goals are to raise awareness of the health impacts of extreme heat and recommend additive built material, legal, and policy education for mobile home residents (Fig. 21.6).

Fig. 21.6

The OSM data on mobile home sites created by YouthMappers at ASU serves as a basemap for new heat-ready trailer park designs

From our studies we learned most Maricopa County mobile home parks/property conditions vary from no vegetation to some vegetation, abandoned rental lots, added carports, added storage units, and an abundance of impervious surfaces. Identifying, collecting, and mapping these hyperlocal forms of microdata sets would provide the varying scales and interrelated impacts of the built environment in mobile home parks. These forms of data are necessary to create site-specific designs, generate cost-benefit analysis, and enlist the investment of local cities and actors to propose solution agendas to protect the health and wellbeing of mobile home residents.

3.3 SDGs as Link from Global to Local Climate Action for Health

Branching from our initial mapping data set, we share this understanding with the entire YouthMappers network to emphasize the different patterns of structural variability. The exposure to extreme heat varies, so local health impacts due to climate change depends on the type and quality of housing / shelter, and demographics of residents in the mobile home parks. In the future, we hope to inspire cross-chapter comparisons of how the built environment impacts the structural performance of housing under conditions of climate change, connecting the concepts of the SDGs, especially 13 climate action and 3 health and well-being through the idea of housing as a right to shelter that saves lives.