[Source: EurekaAlert] — Protect yourself from the summer sun is good advice to children who want to play outside on a hot summer day and it is good advice to cities as a way to mitigate the phenomenon known as urban heat island. For children, a hat, long sleeves and sun block provide protection. For cities, it might be canopies, additives to construction materials and smarter use of landscaping that helps protect it from the sun, said Harvey Bryan, an ASU professor of architecture. Bryan presented several possible strategies a city could use to help it fight urban heat island (UHI) in a presentation he made at the annual meeting of the American Association for the Advancement of Science, held in San Diego, Feb. 18 – 22. Bryan’s presentation, “Digital Simulations and Zoning Codes: To Mitigate Urban Heat Island,” was presented on Feb. 21 in a session on Urban Design and Energy Demand: Transforming Cities for an Eco-Energy Future.
Urban heat island is a phenomenon experienced by large cities, especially those located in desert areas, where the constant heat of the day is absorbed by the buildings, pavement and concrete. The result is a rise in nighttime low temperature for a city’s core from the stored heat of the day. The higher nighttime temperatures mean more cooling is required for residents’ comfort, resulting in increased power demand and potentially more greenhouse gases emitted. Phoenix, where summer nighttime temperatures often do not go below 90 F, is a classic example of the UHI, Bryan said.
Citing work he participated in about a year ago – with Daniel Hoffman, an ASU professor of architecture and Akram Rosheidat, an ASU doctoral student – which focused on ways of improving pedestrian comfort in downtown Phoenix, Bryan outlined several methods a city can employ that will help alleviate the UHI. Shade, not surprisingly, is one of the prime tools. “Canopies to shade streets and sidewalks keep the concrete and asphalt cooler,” Bryan explained. “Interestingly, sidewalks in downtown Phoenix during the early 1900s were canopied.”
Bryan said another key aspect is being smart on material choices for the canopies. “In addition to shading devices, color and thermal properties are also important considerations,” Bryan said. “Lighter colors are best for any surface in the Valley. You also have to consider the heat capacity of the materials – denser material will absorb heat during the day and are slow at re-emitting at night.”
In areas that cannot be canopied, Bryan said material additives use could play an important role. Phoenix, for example, has a large number of parking lots and streets that constantly absorb daytime heat. “Introducing additives, like crumb rubber to asphalt and concrete, are ways of reducing heat capacity at the surface and making for a better nighttime profile,” he said. “The important part is to look at materials performance more than just during the daytime. We need a 24-hour profile to see how materials absorb heat during the day and how they emit it during the evening. We then look for materials that are reflective during the day and highly emitting during the evening.”
All of this points to modeling as an important tool in mitigating UHI. “It comes down to how we model the downtown and how we look at various scenarios with different materials using models that accurately simulate the radiative phenomena,” Bryan explained. “Most cities have never used such powerful tools to find solutions to UHI.”
[Michael Clancy, Arizona Republic] — Meetings are taking place citywide to ask citizens what they like about Phoenix, and what they want to change. The gatherings are the first step in a three-year process aimed at revising the Phoenix General Plan, a document of nearly 500 pages that governs growth and development in the city. “If you want to have a say in what happens — highways vs. transit, sprawl vs. infill, pollution, parks and open space — then you need to get involved,” said Jim McPherson, a civic activist who has volunteered in the effort.
Carol Johnson, a city planner who is managing the process, said meetings will take place over the rest of the year in connection with local village planning committee meetings. “We really need to hear from the community about what they want Phoenix to be, and how we can get there,” she said. “That will define the scope for what we do next.”
Johnson described the general plan as the city’s “long-term guide for the physical manifestation of the city.” She said development of the revised plan would entail a period of “visioning,” in which ideas and goals are developed, followed by a period of drafting policies and measures, and determining implementation.
The plan could include updated sustainability measures, improved business-development plans, revised historical features, and new benchmarks for infrastructure repairs and upgrades. In meetings so far, “there is a lot of interest in climate change and the urban heat island,” Johnson said. “Some people have said the village cores are not working. Others want to see land use and transportation planned in tandem.” She said the plan ultimately would be organized around four subject areas: community, economy, environment and infrastructure.
Catrina Knoebl, a downtown activist, said she expects the process to be worthwhile for the public as well as the city. “I have found the city absolutely listens to citizens,” she said. “They want to hear what residents have to say. They are actively reaching out.” Knoebl said she finds the timing to be advantageous because “we have more people than ever before who are knowledgeable and engaged.”
McPherson agreed the timing is right. “We have a little bit of breathing room now,” he said. “With the slowdown caused by the economy, we have some time to do some thinking.” [Note: Read the full article at Phoenix seeks residents’ input on General Plan revision.]
[Source: Shaun McKinnon, Arizona Republic] — Heat discriminates. Phoenix’s sweltering summer inflicts the most misery and illness in poor neighborhoods, a new study shows, and among people least able to protect themselves from the elements. Conditions in those neighborhoods, with their sparse landscaping, high-density housing and converging freeways, create pockets of extreme heat that persist day and night. Inside, homeowners sometimes can’t afford to turn up — or even turn on — the air-conditioner.
Wealthier homeowners, meanwhile, often in neighborhoods just blocks away, maintain lush yards and trees that help cool the air more quickly at night, shortening the hours of the hottest heat waves. They can buy further relief with a nudge of the thermostat.
The disparities present threats more serious than just discomfort on a hot day, according to the study, produced by Arizona State University researchers. Prolonged exposure to heat can cause illness or even death. The densely developed nature of the hottest areas also means more of the people most vulnerable — the elderly, children, the homebound — live in the neighborhoods where the risk is greatest.
That link between money and the ability to cope with extreme weather emerged clearly in the research. Among the startling revelations: For every $10,000 an area’s income rises, the average outside temperature drops one-half degree Fahrenheit. “It’s an environmental-justice issue,” said Darren Ruddell, a geographer who led the study. “The people who are most vulnerable are also living in the worst conditions. It’s a double whammy.”
The researchers say they hope their findings will spur discussions about better managing land, water and energy use, factors that will grow more critical if temperatures rise in coming years, as climate-change models predict. “If we can identify the areas most at risk, we can try to help them,” Ruddell said. “We could redesign neighborhoods, build cities differently, improve warning systems and ultimately reduce our vulnerability to heat.” [Note: To read the full article, visit ASU study: Wealth buys rescue from metro Phoenix’s urban heat island. Corresponding PDF graphic here.]
[Source: John Talton, Rogue Columnist] — Former Arizona Republic columnist Jon Talton still thinks and writes about his old hometown, Phoenix. Upon returning to his current home from a recent visit and book signing tour in Arizona, Jon wrote the following blog post about the new downtown Phoenix Civic Space (in contrast to this other local blogger’s view):
“…Which brings me to the Floating Diaphragm. That’s what local wags have dubbed the “public art” project that is the signature of the new park on Central Avenue downtown between ASU and the Y. At night, it’s stunning. A floating purple dream. But, as with the Sandra Day O’Connor Federal Courthouse, this is something designed by someone with no knowledge of local conditions. After the first big monsoon, look for the diaphragm in your neighborhood — Gilbert would be appropriate, with its sex phobia and sex scandals.
The park — we’ll see. Phoenix is not good at civic spaces. It’s unclear if it will have enough shade and grass to be inviting year-round. And nobody can stop the creeping gravelization of the once-oasis central city. City Hall sets a terrible example. The old Willo House has been spiffed up as Hob Nobs. But it’s surrounded by gravel and a couple of fake palm trees — who wouldn’t want to be around that 140-dgree heat surface on a summer day? And there are more of them — the natives and long-timers agree the falls and springs have shrunk to a week or two, and winter is getting shorter (and it lacks the frosts that once kept the mosquito population in check). The central city needs lots of shade trees and grass, to offset the heat island effect. It is a much better water investment than new golf courses or more sprawl. Nobody’s listening. Almost: The Park Central Starbucks has made its outdoor space even more lush, shady, and comfy.
Back to the diaphragm. It’s definitely better than the “public art” you whiz by at Sky Harbor because it focuses a civic space, the kind of walkable, gathering places great cities have and Phoenix mostly lacks. Some art at the light-rail stations is quite well done. But, there’s a deadening sameness. My friend, the Famous Architect, likes to rib me, “Not everything old is good.” True enough. But not everything new is good, either. I’d love to see some classical statues and artwork downtown to, say, commemorate the heroic pioneer farmers, the heroic, displaced indigenous peoples, the heroic Mexican-Americans, the heroic African-Americans from this once very Southern town and the heroic Chinese-Americans. Just two or three would offer some contrast and variety, and, I suspect, unsophisticated oaf that I am, elevate and inspire more souls who communed with them. It would also give the lie, in visual form, to the newcomer lie that “there’s no history here.”
Another wish I won’t get. [Note: To read the full blog posting, click here.]
[Source: Kit Stolz, Guest Contributor, Grist Magazine] — During a session called “Sustainability and Growth: How Can a City Develop Sustainably When its Identity is Built on Growth?” at the American Meteorological Society convention, a development expert named Grady Grammage colorfully dispelled some myths and revealed some little-known truths about Phoenix. One myth: Phoenix is unsustainable because it imports water. Virtually all cities import water, Grammage pointed out, even New York, not to mention countless other necessities for urban life, such as food, fuel, and steel. Phoenix arguably has a more stable supply of water than numerous other cities, such as San Diego, because Phoenix imports its water from numerous sources, albeit at great distances.
In Grammage’s view, a bigger question is “habitability,” and he brought up the Urban Heat Island Effect, which he thinks, based on surveys, will drive more Phoenicians out of the state by 2020 than those who move in from other states. Grammage reports that when he expressed this view, various public officials and “water buffaloes” — water experts — in Phoenix scoffed. They think Phoenix could support as many as 10 million people — more than twice its current population.
But the climactic trends may have already been trumped by the economic trends. According to a huge and thoroughly-substantiated front-page story in the Arizona Republic, Phoenix is already losing population — thousands of people — probably due to the economy. Foreclosures are up a mind-blowing 534% from last year, while water hook-ups, trash collection, and sales tax revenues are all down sharply. Substantial numbers of buildings have no water service, indicating abandonment, and sales tax revenues are down 8%. Even crime has declined.
Already, the Phoenix city government has to try and close a 22% revenue gap of about $270 million, and if the state finds that the city is losing residents, it will cut its allocation of tax returns still further. Perhaps this is why the mayor, Phil Gordon, scoffed at the reports of population decline. “The growth of Phoenix, like all cities in the Valley, has slowed significantly. But Phoenix’s net growth is still positive, both in jobs and population,” he said.
Cognitive dissonance, anyone? Or, is it just garden variety denial? In any case, something is in the wind… as reflected in a sign I saw this morning in an empty storefront in downtown Phoenix. Guess we’ll find out what kind of wind it is soon enough.
Hope for a desert delinquent (What Phoenix, the poster child for environmental ills, is doing right)
[Source, Lisa Selin Davis, Grist Magazine, May 13, 2008] — In order for Phoenix to truly be a green city, it would have to be brown. Or not brown, exactly, but the sandy shade of the mountains that surround it: the jagged peaks and parched hills that enclose the Valley of the Sun. These days, though, Phoenix is a less-natural shade of brown; a ring of smoggy pollution known locally as the Brown Cloud shadows the city. And that’s not the only affront to the environs here. Anyone flying in can see the patches of fierce green lawns that paint the landscape, along with the swimming pools; the manmade lake in the suburb of Tempe, evaporating 452 million gallons of water each year; the sea of single family homes spilling across the desert; the traffic clogging the ribbons of highways; and the heat snakes squiggling from all that boiling bitumen. The 517-square-mile city — the fifth-largest and fourth-fastest-growing in America — just survived its second-driest winter on record and is deep in drought.
So how is it that this poster child for sprawl and environmental ills is being hailed — albeit by its own government — as an exemplar of sustainability? City leaders are quick to tell anyone willing to listen that not only are they finally getting hip to environmental matters, they’ve been attending to some of them for upwards of thirty years. From using cleaner fuels in their fleet of trucks and buses to implementing an environmental purchasing program, from building a new 20-mile light-rail line to signing the U.S. Conference of Mayors’ Climate Protection Agreement, officials have taken concrete steps to right past wrongs.
Perhaps more important than these piecemeal sustainability steps is the city’s partnership with the local university. What’s wrong with the city — the temperature’s rising, for one thing, and development is still skidding out of control — is what makes it such an attractive candidate for a living laboratory. The city’s environmental deficits are educational opportunities for the students and teachers of Arizona State University’s four-year-old Global Institute of Sustainability. “When Phoenix is done growing, it will be bigger than Chicago,” says Dr. Michael Crow, president of ASU. “The next massive city of the United States isn’t done yet.” GIOS, then, has a chance to affect these latter stages of growth. And what GIOS gleans from Phoenix just might change the way other desert cities behave — that is, if it’s not too little, too late. [Note: To read the full article, click here.]
[Source: Shaun McKinnon, Arizona Republic] — In the old comic books, the vilest super-villains brandished an exotic weather-control device to threaten the world’s cities. Turns out all the villains really needed were the cities, whose growth increasingly influences the weather with devices no more exotic than an office building or a freeway. Those devices can raise temperatures to unhealthful levels, steer storms off course or alter their intensity, suck the rain out of clouds and may contribute to long-term climate change. Worse, sprawling metropolises can foil efforts to forecast the weather or even track a single event. “There’s no doubt man has impacted his local environment,” said Tony Haffer, meteorologist in charge at the National Weather Service in Phoenix. “It’s reached the point that it’s more than just meteorologists and climatologists looking at this. Engineers that build and plan cities are looking for ways of mitigating the effects of putting in more concrete and asphalt.”
The real-life power of urban areas to shape and reshape weather and climate is the theme of the American Meteorological Society’s national conference, which runs through this week at the Phoenix Convention Center. More than 2,000 meteorologists, climatologists and even a few engineers are expected to attend. The program includes discussions about public-policy issues, but the intent isn’t to deliver solutions or formal recommendations as much as it is to support the scientists searching for the solutions. Some of the research presented this week will offer concrete ideas for businesses or governments to use, while other projects will guide future studies.
Phoenix provides a fitting backdrop for the gathering: It was here that scientists conducted some of the earliest research into the urban-heat-island effect, the increase in nighttime temperatures that occurs when buildings and roads release energy absorbed during the day. The city’s rapid growth has given scientists a living laboratory to test theories and chart discoveries. [Note: To read the full article, click here.]
[Source: Cynthia Weaver, City of Phoenix] — The city of Phoenix has updated its Sustainability Summary increasing the total number of sustainability programs from 70 to more than 80. The summary provides brief descriptions of all of the city of Phoenix’s environmental stewardship efforts, some of which have been in place for decades. “To be successful, Phoenix must be an environmental leader. This summary showcases Phoenix’s numerous environmental programs,” said Councilman Greg Stanton, chair of the Parks, Education, Bioscience, and Sustainability Subcommittee. “The depth and variety of programs demonstrates that Phoenix is an environmental leader, both in the Valley and throughout the nation.”
The updated summary includes recent information on the city’s Climate Action efforts and participation in Earth Hour, in addition to new information about Phoenix Recycles, Bag Central Station, the Convention Center solar project and the city’s recently adopted renewable energy goal, the Brownfields Environmental Technician Job Training Program, and Environmentally Preferable Purchasing Program. Enhancements have been reported in the areas of air quality and transportation, environmental leadership, green building and energy conservation, heat island, historic preservation, land use policies, pollution prevention, riparian area conservation, and water conservation. To view the complete summary online, click here.
[Source: William Hermann, Arizona Republic] — By helicopter, by automobile, even by Pedi cab, Professor Harindra Fernando’s researchers covered the Valley Friday in an intense investigation of an intensely uncomfortable phenomenon called the “urban heat island.” Fernando and his Arizona State University engineering colleagues are trying more exactly than ever to define the heat-trapping effect that in the summer months turns much of the Valley from a place that was once hot but habitable, to something of a hell-on-earth.
The point is to help government and private enterprise slow and even reverse the central-Valley heating trend. “Our freeways, streets and structures all hold in heat, creating a reservoir of heat in the Valley,” Fernando said. “There was almost no heat island effect in the Valley until the late 1940s but it was rising by the late 1950s and has risen quickly since then. If you keep increasing the heat island effect, as we have, at some point it will become so uncomfortable that people will start leaving the Valley. It becomes the difference between comfort and misery.” [Note: To read the full article, click here.]