Here Comes the Sun

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Swimming pool at the Jokake Inn, circa 1940s. Historical photos provided by Arizona Historical Society

Arizona’s bright days and balmy nights have lured generations of Americans. But will our ever-hotter and longer summers spoil the party? In the final feature of our Five Cs series, we explore ways people are trying to cool our cities and harness the power of our climate.

This summer, try an experiment: As you go about your day, observe closely everything to do with temperature and light. Feel your skin prickle as heat sizzles off the Valley’s expanses of sun-sucking black asphalt. Pause in the anorexic shade of a palm tree trunk. Sit on a bench exposed to the sun, burn your thighs and stare across the street at the shaded area with no benches. Drive the freeways, glancing at roadside shade trees, and imagine how much more they’d benefit that sweltering South Phoenix park where no kids play, or utility-deprived homes where people bake, sometimes to death. Stand in the ironic waste heat generated by air conditioning units, and picture the electricity zipping back to its sources: Just 5 percent of our electrical power comes from the sun; most comes courtesy of coal, gas and uranium.

In other words, pay attention to how the Valley handles its climate, and you’ll shake your head in wonder.

Climate is the biggest of the Five Cs, Arizona’s historic economic drivers. It’s too big to quantify. It fuels our tourism and agriculture. It attracts our residents and businesses, suffusing our culture, politics and economy.

It’s also morphing from an asset into a liability. Phoenix is the fastest warming big city in the country, according to National Oceanic and Atmospheric Administration data. Economic developers often say the Valley is a great place to locate because we have no natural disasters – but that’s debatable. Between 2006 and 2010, 50 to 85 people died from heat each year in Maricopa County. In 2016, it was 150. That’s more than Hurricane Harvey or Irma. When the investigations wrap, 2017’s death toll could reach 180. “This is really a public health crisis,” says Melissa Guardaro, a research fellow at Arizona State University’s School of Sustainability.

There’s a debate over how “livable” Phoenix will be when urban heat effects and climate change push us to an estimated 147 days over 105 degrees by 2050 (about a month more than we endure now), according to scientist-run nonprofit Climate Central. It depends on your definition of livable, some say. But we can all agree that livable means “doesn’t kill you.” And for most people, a livable city is one in which they can enjoy going outside and operate businesses that don’t take a heat-induced siesta for 147 days.

Happily, momentum is building to redesign Arizona to be smarter about climate. Phoenix is a finalist in Bloomberg Philanthropies’ 2018 Mayors Challenge and could win $5 million this fall to implement a first-of-its-kind HeatReady program. Numerous groups are collaborating to cool the city and help communities respond to extreme temperatures. And proposed legislation would dramatically amplify Arizona’s solar and clean energy portfolio.

“The sixth C is ‘Clean,’” says Arizona Corporation Commissioner Andy Tobin. As long as we don’t succumb to another C – complacency – Arizona could once again make an ally of the sun.

 sunbathers pose at the San Marcos Hotel for an American Airlines promo, circa 1940s. Historical photos provided by Arizona Historical Society

In the early 1900s, physicians were incandescent about a newly discovered panacea for typhoid, asthma and tuberculosis: the Sun. Through the magic of heliotherapy (sunbathing), “the proportion of cures in advanced and apparently hopeless cases of surgical tuberculosis seems incredible,” enthused Dr. Guy Hinsdale in 1919.

“The fine muscular development of many tuberculosis patients who are taking heliotherapy but no exercise is [striking],” raved Dr. Carl Howson in 1928. “It has been suggested that this latter is due to the continuous light massage of the skin by the moving air.”

Thousands of people were given the same prescription: “Go to the sunny West.” Around the turn of the century, an estimated 25 percent of pioneers who settled west of the Mississippi did so for health reasons. Wealthy TB sufferers recuperated in sanatoriums like Castle Hot Springs near Lake Pleasant. Poor “lungers” – as coughing consumptives were called – holed up in Arizona’s first Tent Cities, in Sunnyslope and Tucson. Doc Holliday, Barry Goldwater’s mother and Sun City founder Del Webb all came to Arizona to relieve TB or typhoid. While Arizona’s other Cs – copper, cattle, cotton and citrus – lured pioneers mainly to rural areas, solar-seeking sick people typically settled in cities, shaping Phoenix and Tucson’s early populations, zoning and businesses.

How did those heliophiles cope with summers before air conditioning? Wealthy wives and children were sent to cooler climes, so the dog days of Phoenix were notorious for steamy affairs between businessmen and their “summer wives.” Residents who remained got creative. They swam in the Salt River and water-skied the canals, pulled by cars. Families slept on patios hung with wet blankets, or put cots and sheets on the lawn, then purposely wet the bed – with a hose. (See The Big Chill on page 42.) The Oliver Twists of Arizona cranked giant fans in restaurants and hotels. Staff at Downtown Phoenix’s Adams Hotel invented the first “air conditioning”: fans blowing across 300-pound blocks of ice. Homeowners fashioned evaporative coolers from fans blowing through apple crates, wet sheets, charcoal and wood chips. Ample trees and porticos created continuous corridors of shade.

Our predecessors also had an advantage. In 1913, Phoenix hit 100 degrees-plus on just 48 days. In the first half of the century, summer nights sank into the 70s. Then Phoenix’s climate became a victim of its own popularity. As more people were attracted to the Valley’s weather, the city grew to accommodate them. Rural areas were converted into Rural Road. Saguaros and citrus trees were swapped for skyscrapers. Once we could turn up the air conditioning, we turned down our minds when it came to heat-smart design. Phoenix became an urban heat island (UHI).

All day, asphalt and metal absorbs oven-like heat. When the sun sets, roads and buildings cool by releasing that heat into the air. The result: Phoenix nights are 10 to 15 degrees hotter on average than those in the surrounding desert, though it can be as much as 23 degrees. Daytime is also more sweltering: Due to both climate change and the UHI, in 2013 the mercury hit 100 degrees-plus on 115 days.

early glamping enthusiasts enjoy a Wonderbus tour organized by brothers Warren and Charles McArthur, who later founded the Arizona Biltmore, 1929; Historical photos provided by Arizona Historical Society

Scorching temps harm the economy, the environment and health. Last June, Phoenix Sky Harbor International Airport canceled more than 40 flights because it was too hot. As summer melts into October and April, tourists could be deterred from visiting the Valley during high season. Heat spikes energy use, increasing bills by hundreds of millions of dollars, along with carbon emissions, air pollution and water use. For every degree above 70, we choke on 3 percent more smog, according to the U.S. Department of Energy.

But “island” is misleading. “There’s not one urban heat island, but rather a string of microclimates,” says Guardaro, who works in ASU’s Urban Resilience to Extremes Sustainability Research Network. The hottest archipelagos are often low-income neighborhoods, roasting amid asphalt and bare yards. In these areas, many people have only evaporative cooling or can’t afford to turn up the A/C. These hot spots should be priority
No. 1 for relief, Guardaro says: “You go where it’s hottest, where people are, and where the most vulnerable people are.”

So Guardaro and other ASU researchers teamed up with the Nature Conservancy and Maricopa County Department of Health to design a cooler future for three neighborhoods: Edison Eastlake east of Downtown, southwest Phoenix and the Watertower Improvement Area in Mesa.

Instead of experts dictating design based on data, they’re gathering stories from residents about how they cope (or don’t) with heat. Then they’ll use proven strategies to rewrite those stories into more temperate narratives. “Story is emerging as a great way to engage residents and ground the work in people’s experiences and truth,” says Maggie Messerschmidt, the Nature Conservancy’s Healthy Cities program manager.

For example, a woman might hypothetically say, “Every week I walk along this scorching street to the grocery store. One day, an elderly man fell on the asphalt and burned his skin. I called 911. There was no shade, so while we waited, my groceries melted, but I couldn’t afford to shop again.” How could that narrative be rewritten? The woman might walk instead along streets painted with special pastel paint that cools asphalt by up to 15 degrees – an intervention recently implemented in Los Angeles. She could be shaded by 25 percent tree canopy, which can cool unvegetated neighborhoods by 8 degrees, according to a 2014 ASU study. Trees need water, but there are ways to be water-smart. “We really have to take a systems viewpoint,” Guardaro says. “There needs to be a strategic tree planting effort… It’s the right tree in the right place with the right configuration.”

After walking under native, drought-tolerant mesquite and ironwood on the sidewalk, the helpful shopper and her elderly friend could seek shelter under lusher trees in a park or garden, where the plants create a cool gathering place and perhaps produce food. The man could also have easier access to dedicated public cool spaces through an expanded Heat Relief Network.

This “thermal editing” could rewrite stories throughout the city. Workers could escape their cubicles and lunch alfresco if more artful shade structures cooled and beautified the city. Drivers could hold their steering wheels without potholders if parking lots were shaded by trees, which can reduce vehicle interior temps by 47 degrees, according to the U.S. Forest Service. (Alternatively, solar panels – which can increase the UHI when placed on low roofs – could shade parking lots, cooling cars and asphalt while powering buildings.)

Residences and buildings could be designed with heat-resistant materials and breezeways, and oriented to throw maximum shade, saving A/C costs and improving quality of life. In Edison Eastlake, residents and researchers are brainstorming about the combined benefits of housing with a courtyard, trees and evaporative cooling tower. “The cooling tower would become more efficient with trees around it, and it would complement the cooling effect, so you could get up to a 30-degree reduction outdoors,” Messerschmidt says. “I love the types of solutions that seem to complement other solutions.”

Remnants of Arizona pioneer Jack  Swilling’s thick-walled adobe home,1920. Historical photos provided by Arizona Historical Society

“We need collaboration from everyone,” Guardaro says. “When developers develop new sites, they [should] keep thermal comfort top of mind for their residents and the people that work there.”

Tempering the UHI would save lives, make the Valley a more desirable destination, and trim energy costs. But that still leaves the problem of climate change. To help with that, Arizonans must curb carbon and air pollution – plus give our energy portfolio some heliotherapy.

Drive a side road south of Eloy, and you can trace part of Arizona’s power evolution. First, you pass an industrial forest of gas turbines and towers. Then, old-school solar panels that resemble funhouse mirrors. Finally, 182,000 sea-blue solar panels, like an abstract ocean in the desert. This is the Red Rock Solar Project, a collaboration between Arizona Public Service (APS), ASU and PayPal. The 40-megawatt plant beams enough energy to power 10,000 homes. ASU and PayPal help finance the APS-owned project by purchasing its equivalent energy output as renewable energy credits.

This photovoltaic array is the vision of many Arizonans: blue solar panel “seas” in the desert, solar panel “ponds” over parking lots, solar panel “puddles” on roofs. Yet as of 2016, solar generated just 5 percent of Arizona’s electricity, according to the U.S. Energy Information Administration. Natural gas and nuclear each generated one-third, while coal supplied one-fourth.

Renewable energy advocates say the planned 2019 closure of the Navajo Generating Station – the state’s largest coal plant – represents an opportunity for clean energy such as solar to eclipse fossil fuel-burning power plants, which cause up to 52,000 premature deaths annually in the U.S., according to a 2013 MIT study, manifested as lung cancer, heart disease, asthma and other disorders.

Advocates agree that eclipse isn’t happening fast enough.

“Our state doesn’t have a climate change plan, and it means we’re not keeping up,” says Sandy Bahr, director for the Grand Canyon Chapter of the Sierra Club. “We don’t have a plan for how we reduce emissions [or] how to adapt, because we know temperatures are rising, we know precipitation is becoming more erratic, and certainly there’s less of it… Even if you don’t think of it as purely climate, we don’t have a state energy plan yet, either.”

But a new era is dawning. In the past few years, utility-scale solar has become cheaper than nuclear, coal and natural gas, making solar economically and environmentally brilliant. For the first time, the Arizona Corporation Commission (ACC), which regulates utility companies including APS, voted in March to reject the utilities’ 15-year plan, saying it relied too heavily on natural gas. That surprised people, because APS’ parent company, Pinnacle West, spent $4.2 million ensuring the elections of its regulators, who have historically supported fossil-fuel-focused plans.

 Locals kept cool by lounging in the mist of SRP’s Grand Canal falls, 1909. Historical photos provided by Arizona Historical Society

In another surprising move, Commissioner Andy Tobin proposed a plan that calls for 80 percent clean energy by 2050. “It’s the most aggressive energy plan in the country,” Tobin says. “We wanted to make sure that we picked a large goal to get to clean, but we also wanted to pick a goal that was achievable.”

His plan – currently in the rulemaking stage – calls for boosting solar battery storage, electric vehicles, energy efficiency and “clean” energy including nuclear and biomass. The latter would come from thinning forests to help prevent wildfires, then burning the wood for energy. (There’s controversy over what’s clean; the Sierra Club does not consider nuclear clean and says biomass burning is problematic. Solar panel manufacturing can produce chemical pollution, though standards requiring companies to recycle waste are now in place.)

In addition, a ballot measure was introduced in February called Clean Energy for a Healthy Arizona. It would require 50 percent solar-centric renewable energy by 2030. But it suffered two successive blows. Governor Doug Ducey, who’s also supported by APS, signed a bill saying that if the measure passes, the utilities’ penalty for non-compliance would be a wrist-slapping $100 to $5,000. Then a senate committee passed a bill, proposed by APS, that launched an almost identically named competing initiative: Clean and Affordable Energy for a Healthy Arizona. This initiative contains an escape hatch that prevents the ACC from implementing renewable energy requirements if they would adversely affect cost, reliability or “the well-being of the state.”

Pending approval, both measures could be on the ballot this November. Bahr says the second initiative is designed to confuse voters with its similar nomenclature; she’d like to see voters pass the original initiative.

There’s no question Arizona’s solar industry should eventually go stratospheric, but utilities have concerns about switching too quickly. “Solar is really good because it’s clean power. [But] it goes to sleep,” says Jim Piotrowski, APS’ director of distributed energy resources. Solar can produce more energy than necessary during the day, then slumbers during peak hours when people come home and crank the A/C. It also creates a surplus of energy during our balmy winters.

“That’s why [battery-based] energy storage needs to play a bigger part in all energy portfolios,” Piotrowski says, adding that APS is currently commissioning its third utility-scale battery.

While battery prices have plummeted, they’re still extremely expensive and typically store solar energy for only four hours. “We need to have power 24 hours a day, seven days a week, and batteries don’t do that right now,” says Anne DeGraw, communications consultant at APS. “So we need to have a gas plant that we can turn on, or a coal plant or Palo Verde [nuclear plant].”

Sandy Bahr, head of the Arizona Sierra Club, at Wesley Bolin Plaza in Downtown Phoenix, believes additional tree shade can cool the urban heat island.

With rate incentives, APS is encouraging people to use more power when solar energy is abundant by, for example, precooling their homes. APS also champions commercial partnerships like the Red Rock Solar Plant and a project with First Solar to build a 55-megawatt solar array plus 50-megawatt battery. “We want cleaner energy,” says Jeff Burke, APS’ resource planning director. “But [the First Solar project is] the first one we’ve seen that met our needs. We think it’s the way things should be going into the future.”

For the future to go that way, utilities must adopt business models that embrace utility-scale and rooftop solar, buoyed by batteries that continue to drop in price. Cities and citizens also need to get involved by shrinking the carbon and air pollution output of vehicles and buildings. It seems daunting, but an innovative effort at ASU could make it manageable and affordable.

The Hestia Project uses sensors and data mining to quantify a city’s carbon dioxide emissions at the level of buildings and streets. In Hestia’s simulations, a city’s major emitters stand out like giant red Monopoly hotels, and traffic jams rise like tsunamis.

“When you look at a city and you’ve got a lot of granularity, you see that actually it’s a few things that dominate the emissions landscape,” says Kevin Gurney, an atmospheric scientist who directs Hestia. “If you’re going to reduce your emissions, don’t waste your time tackling your entire landscape. You’re far smarter to go after these big things, because you’ll get far more emissions reduction at a much cheaper cost.”

For example, New York City used similar data and discovered that most of its pollution was caused by 1 percent of the buildings burning one type of oil. It changed that one thing and reduced greenhouse gases by the equivalent of eliminating 160,000 cars.

Hestia, which has gathered data for five cities, could help Phoenicians make decisions about where to locate public transit routes or relieve traffic, and which buildings need an energy-efficiency revamp. Unfortunately, the City of Phoenix lost interest in the project, Gurney says. He says that’s a shame, because if we’re going to redesign Arizona to be climate-smart, we need to think carefully and creatively, armed with comprehensive information.

Cool Town: High-tech and traditional methods can help us tame urban temps.

“To really take a significant bite out of the climate change problem in the next 50 years,” Gurney says, “we really have to dig deep into the entire planning process and plan cities differently and improve the quality of life for everybody.”

Across this Five Cs series, three common Cs have emerged. Conflict: Utility companies and clean energy advocates, copper miners and conservationists seem separated by an ideological Grand Canyon. But once you delve deeper and connect through conversations, it becomes clear that everything is infused with a second C: complexity. There is no completely right or wrong side. There are no simple problems and therefore no simple solutions. For cattle ranchers and cotton farmers, what makes one field thrive may not work in another. What cools one city block may increase temperatures in the next. But as we’ve seen in the Nature Conservancy’s collaborations with grassland-growing ranchers and river-saving farmers, or the community citrus exchanges that feed the less fortunate, we can solve problems – even something as big as climate – if we engage in the greatest C: cooperation.

PHX Heat Facts

First 100-degree day in Phoenix annually
Earliest: March 26, 1988
Latest: June 18, 1913
Average: May 12

Last 100-degree day in Phoenix annually
Earliest: September 2, 1904
Latest: October 23, 2003
Average: September 28

Greatest number of consecutive days with max temps of 100°F or higher
76 in 1993

Most number of days with max temps of 110°F or higher
33 in 2011

While it’s true that Phoenix has always endured its share of triple-digit summer days…
Average number of days with max temps of 100°F or higher (1896-2010)

… the frequency of such days has climbed sharply over the past century.
Average number of days with max temps of 100°F or higher (1981-2010)


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