That is how Portlanders might describe the nearly incessant stretch of above-average temperatures this summer. June, July, and August were sweltering, bringing record-breaking heatwaves and weeks without measurable precipitation. Unusual as the weather may have been, some climate models suggest this is the new norm.
As summers have been historically mild in the Pacific Northwest, the shift to warmer weather for longer periods of time could place the Rose City and its residents under considerable stress. High temperatures, particularly in areas referred to as “urban heat islands” pose serious health risks. The danger is compounded by the increased presence of respiratory irritants like smog and ozone that form when heat alters the chemistry of emissions from motor vehicles and industrial operations.
On days of extremely high temperatures, in neighborhoods where the heat island effect and poor air quality intersect, the health of vulnerable populations—older adults, very young children, the unhoused, those without access to services, and residents with cardiovascular or respiratory diseases—is in jeopardy. That means Portland, and cities like it all over the world, are facing the potential of a climate-change-induced public health crisis.
Into the fire indeed.
Above: Ladd's Addition's established and lofty canopy makes it stand out as an urban cool island.
The likelihood of such a crisis, however, can be greatly reduced. The City of Portland, being on the leading edge of action to reduce carbon emissions and prepare for the effects of climate change, has a plan to transform the Rose City into one of the most climate-resilient cities in the world.
Portland’s Climate Action Plan calls for reducing the heat island effect, minimizing health issues related to degraded air quality, and using data-driven, up-to-date maps “to help inform decisions and priorities about projects and programs that help cool the urban environment.”
To complete these actions by a 2020 deadline, the city enlisted the expertise of PSU’s Dr. Vivek Shandas and a handful of other talented PSU faculty with expert knowledge of disciplines related to sustainability science. Shandas’s team includes Drs. Todd Rosenstiel (Biology), Linda George (Environmental Science and Management), and David Sailor (Mechanical and Materials Engineering). The PSU team works in collaboration with the city, state, NGOs, and community groups to assess human vulnerability to heat stress and air pollution within the city. Their project is funded by PSU’s Institute for Sustainable Solutions (ISS) through a grant from the Bullitt Foundation and is a part of the Portland Climate Action Collaborative, a partnership between ISS and Portland’s Bureau of Planning and Sustainability that focuses on research-driven solutions to urban sustainability problems.
“To prepare for the possible negative health impacts of extreme heat and air pollution, we have to know where heat islands are and air pollution is concentrated,” said Dr. Shandas, Associate Professor of urban studies and planning. “We also need to know where our vulnerable residents are. Then when we layer all of that data on a map, we can clearly see where we need to direct our efforts.”
During the first phase of the project, ISS organized a series of workshops that identified a number of characteristics indicative of vulnerability to heat stress and poor air quality. Those included factors such as age, income, health, the presence of air-conditioning, and access to city services. Using those conditions, the team analyzed city demographic data to reveal at-risk populations.
The population datasets were combined with tree canopy cover for the city, street-level traffic-related air quality records, and high resolution, GPS-located temperature measurements by PSU Geospatial Research Analyst Jackson Voelkel. When combined and layered over a map of Portland the data identified, in vivid color, areas where the city and its partners need to concentrate efforts to mitigate the heat island effect, improve air quality, and protect public health.
“An advantage of using maps as a tool to present complex issues like managing heat islands in urban settings is that you can communicate huge, complicated data sets in a very accessible way,” said Mr. Voelkel. “Maps can help people visualize the unseen world around them. Anyone can see trash on the street. You don’t necessarily see air pollution. A map like this changes that.”
The map, which is part of an online, interactive toolkit Dr. Shandas is creating in the Sustaining Urban Places Research Lab, will soon be available for public use. When it comes online, users will be able to explore Portland like never before: peering into its hot spots, polluted zones, and comparing their neighborhood to others. They will have the means to explore the relationships between tree cover, heat, pollution, and public health right in their own backyards.
“We really hope this map will get people asking questions,” Dr. Shandas said. “‘Is my neighborhood an urban heat island?’ ‘What can I do to cool the neighborhood down?’ ‘Is the air quality in this park healthy enough for a child with asthma to play in?’ ‘Should the neighborhood establish a plan of action to keep vulnerable residents safe during heat waves?’”
Now that the trouble zones are in plain sight, city and community stakeholders are beginning to act to reduce the heat island effect and improve air quality throughout the city with a focus on those areas identified by the PSU team. As Dr. Shandas noted, no single action will prove successful, but many actions all working in concert could have a significant impact.
“We need to start preparing for the effects of climate change,” said Dr. Shandas. “Which means we need to start a conversation about how people, particularly those in cities, will be exposed to extreme heat, degraded air quality, fires, floods, landslides, and other events.”
That conversation has begun. Researchers at PSU are helping the community identify vulnerable neighborhoods and populations. The city is putting its climate initiatives on the map. And while improving Portland’s climate resiliency may not exclude us from longer, hotter summers in the future, it will no doubt improve the protection we can provide to our most vulnerable residents.