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Keeping Our World Cooler for Now Will Make It Permanently Hotter

  The following is taken from a presentation by Stan Cox to the New York Academy of Medicine and the Museum of the City of New York on August 11, 2016: The headlines screamed, “Kerry says AC more dangerous than ISIS!” The Secretary of State, at a conference in Vienna last month on reducing the…

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Stan Cox


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The following is taken from a presentation by Stan Cox to the New York Academy of Medicine and the Museum of the City of New York on August 11, 2016:

The headlines screamed, “Kerry says AC more dangerous than ISIS!”

The Secretary of State, at a conference in Vienna last month on reducing the use of the refrigerants – powerful greenhouse gases that are used in refrigeration and air conditioning – had actually said this:

“Yesterday, I met in Washington with 45 nations . . . as we were working together on the challenge of ISIL and terrorism . . . What we – you  – are doing here right now is of equal importance because it has the ability to literally save life on the planet itself,"

I couldn't agree more with Kerry's point about the catastrophe that awaits us if we don't stop greenhouse emissions. But it was his bad luck that, at the time he made that statement, a vast heat dome  had parked itself over our lower 48 states, triggering a panicked rush in every city for the nearest compressor-cooled space. 

I have learned the hard way that a heat wave is the very worst time to kick off a rational debate on the pros and cons of air conditioning. Sure enough, Kerry took a beating in the media. So I hope the weather is moderate where you are as you read this.  

Marooned on Heat Island

Heat waves were responsible for one out of four deaths from U.S. weather disasters between 1995 and 2015. But through all that time, the heat-related death rate has been declining steadily thanks in part to increased availability of home air conditioning. 

Yet heat-related deaths are far from being eliminated, especially in so-called “urban heat islands,” where solar energy absorbed by concrete, asphalt, stone, and steel during the day keeps the nighttime hotter than in nearby rural areas. Air pollution heightens the danger. The warming effect is especially high on the heat island and literal island of Manhattan, where night temperatures can be elevated by more than seven degrees F. 

With close to 90 percent of U.S. homes now air-conditioned, death by heat has become rare in much of the country. It's now concentrated in demographic and geographic hotspots—typically in economically forgotten, concrete-rich, vegetation-free stretches of larger (mostly northern) cities. Heat most often strikes people of advanced age or in poor health, those who are socially isolated, and those who cannot afford to install an air-conditioner or could not pay their electricity bill if they did so. 

Here in New York as in other cities, death rates are higher in neighborhoods where air conditioning is less prevalent, but those are also neighborhoods that tend to have higher poverty rates and are home to more African-American and Latino families. 

In every U.S. city, people and families who have central air conditioning (and who thereby almost always survive heat waves) also have higher incomes, larger, newer houses, better plumbing, and higher education levels, all of which are also associated with lower heat-related mortality. During the terrible Chicago heat wave of 1995, a series of power outages (triggered, by the way, by heavy use of air conditioning) knocked out the air-conditioning in both rich and poor neighborhoods. But it was on the South Side, not up on the Gold Coast, where the lion's share of the 700 or more heat deaths occurred.

In the years since Chicago '95, air conditioning has tamped down the heat-death rate. But the amount of electricity burned for residential air conditioning has doubled. Only a tiny portion of that increase went to saving lives.

For people struggling to survive heat emergencies under difficult conditions, air conditioning should be recognized as a fundamental right, and access should be assured. But only a small fraction of the total energy that America uses for air conditioning is expended during heat emergencies to keep people alive, healthy, and comfortable. 

It would be inhumane to cut back on that use, but while air-conditioning has become a necessity in such circumstances, it is not a solution. It plays the same role as an ice bath for a patient suffering an extreme fever, treating the symptom while leaving untouched the root cause—in this case, the distorted ecological, economic, and social structure of our cities. 

Much more easily addressed is the routine, lavish use of air conditioning that can reach bizarre extremes. 

I read last month that a new ordinance here in New York that will fine stores and restaurants $250 or more if they keep their doors or windows open while running the air conditioning.  “But,” says the Times, “as temperatures soared into the 90s, some air-conditioned shops and eateries around Times Square still had doors propped like open arms, beckoning passers-by to come into the cold.” 

That's just one of many outlandish examples of AC over-use. Any of you who have had to carry a sweater to the office or to a restaurant in August would have your own stories. But if we eliminated all ridiculous overuse, air conditioning would still have a too-heavy impact.  

Birth and Death of the Cool

By making our world temporarily cooler, air conditioning is making it permanently hotter, thanks to the increases in greenhouse emissions. 

I roughly calculate that in the United States, greenhouse emissions from (a) electric utilities to air-condition buildings, (b) burning of excess fuel to air-condition vehicles, and (c) escape of refrigerants during manufacture, operation, and disposal of air conditioners add up to about 500 million tons of carbon dioxide equivalent per year. 

Academia and media ignored that enormous impact up until a few years ago. Then estimates came out that if the rest of the world starts being able to afford air-conditioning, emissions could go from a billion to 10 billion tons a year, and suddenly refrigerated comfort became a major problem! But unless we do something about our own air conditioning use, we have no standing to lecture the rest of the world. 

 If the second, fourth, and fifth most populous nations —India, Indonesia, and Brazil, all hot and humid —were to use as much energy per capita for air conditioning as does the third-biggest country, the U.S., it would require 100 percent of India, Indonesia, and Brazil's electricity generation, plus all of the electricity generated by Mexico, the United Kingdom, Italy, and the entire continent of Africa.

It's time to question the prevailing assumption that cities like New York can adapt to more frequent heat waves in the future simply by using even more air conditioning. That will be an exercise in tail-chasing. It will also do nothing for the millions of people who work outdoors or in industrial plants, well out of air conditioning's reach. Global warming will take an especially harsh toll on them. 

In fact, thanks to greenhouse warming, the long-term decline in rates of heat mortality that we have seen in recent decades may bottom out and reverse, no matter how hard we run the air conditioner. 

In 2007, researchers at Columbia University projected heat-related death rates in the New York City region out to the year 2050 under four scenarios: with and without action to curb greenhouse warming, and each with or without “acclimatization.” (Acclimatization included increased use of home air-conditioning, heat alerts, and community cooling centers.)  They predicted that by 2050, if neither climate mitigation nor acclimatization is pursued, the rate of heat-related mortality in and around New York City will be almost double what it was in pre-greenhouse 1990. With either modest mitigation measures or adaptation but not both, the heat-death rate will be about 70 percent higher. With both measures, it will still be 47 percent higher. 

The implication is clear: air conditioning can't save citydwellers from the greenhouse conditions that it helps create. So how did we get to this point?

New York has a solid claim to be the birthplace of the cool. The first air conditioning system was developed by Willis Carrier for the Sackett-Wilhelms Lithography Company in Brooklyn. Installed in 1902, it was designed not for the comfort of workers but rather to reduce the summertime humidity that interfered with the printing process. That same year, the first AC system designed for comfort was installed by Alfred Wolff in the trading floor of the New York Stock Exchange.

Adoption of residential air conditioning proceeded slowly in the northern states. The share of New York City households with air conditioning remained below 15 percent in 1960 and was still just 38 percent in 1970. In New York department stores of the twenties, conditions could be quite miserable in the hottest weather, and business fell off to near zero. Even so, they were very slow to adopt air conditioning because, according to historian Marsha Ackermann, they wanted to attract affluent customers, and in those early days, the urban rich tended not to show much interest in the novelty of refrigerative cooling. That, it was assumed, was for the masses; the rich had their beach houses.

Ackermann reports that in those days, upper-class Americans “had an inbred habit of ignoring discomfort.” Their tolerance of oppressive warmth and humidity, it was believed, extended to the retail realm. Ackermann wrote, “The slow acceptance of storewide air conditioning reflected not only its high cost but also a common belief that gentlewomen, and the type of women fit to serve them, were by nature and culture less bothered by heat.” Indeed, air conditioning was first installed in the “bargain basements” of department stores, not the upper floors where luxury goods were on offer. 

"It Makes It Too Hot Outside"

Today, the tradition of air conditioning in the bargain basement has been turned on its head. On a humid 79° day in June 2005, the New York Times confirmed what many suspected: the more upscale retail establishments of Manhattan push their air-conditioning systems harder. Reporter Allen Salkin found that “the higher the prices, the lower the temperatures: Bergdorf Goodman, 68.3 degrees; Bloomingdale’s, 70.8; Macy’s, 73.1; the Original Levi’s store, 76.8; Old Navy, 80.3.” 

A Bergdorf Goodman vice president defended the store’s chilly conditions: “It’s part of the whole environment package that we try to offer our customers.” A retail consultant told Salkin, “There is still status symbol in almost over-the-top air conditioning.”

And 114 years after the stock exchange was first air conditioned, New York's financial district is thoroughly refrigerated.  A Wall Street stock trader told the Times that the room where he worked was kept “icy” because “we get stirred up during big trades, and we’ll complain if it’s too hot.” He added that, during slack periods, “we all have fleeces we wear.”

Office climate control can not only chill you; it may make you sick. In tightly sealed, air conditioned buildings with low ventilation rates, incidence of respiratory illness is increased by 50 to 120 percent, according to one review of the health literature. Studies in California, Brazil, Argentina, France, the United Kingdom, Denmark, and elsewhere showed that people employed in air conditioned workplaces had poorer health and spent more time in physicians’ offices and hospitals. A commentary on one of the studies, in the International Journal of Epidemiology, read in part,

Occupants of office buildings with air conditioning systems … consistently report, on average, more symptoms in their buildings than do occupants of buildings with natural ventilation. This has been the finding in many studies over the last 20 years, and in three reviews. The symptoms in these studies have included mucous membrane irritation, breathing difficulties, irritated skin, and constitutional/neurological symptoms such as headache and fatigue.

Initiatives to wean society away from the overuse of air-conditioning will be self-reinforcing. We know that extensive exposure to air conditioning reduces the human body's capacity to tolerate heat; conversely, the more we live with warm weather, the more we will will be able to tolerate it. 

Responding to a sociologist's survey in 1992, an apartment resident of Davis, CA put it best: "We don’t use the air conditioner because it makes it too hot outside."

But climate adaptation can work only if it's linked to stopping global climate disruption, and both require us to start digging up root causes. Acute problems should have priority. We must make the most distressed urban hot zones livable again, by jackhammering concrete, re-creating green space, improving the quality of housing and health care, reviving local economies, and restoring the social networks that once sustained the communities.

To reduce air-conditioning dependence in more prosperous urban areas will require a serious overhaul: year-by-year shrinkage of parking and driving space accompanied by improvement of public transportation; de-paving and revegetation of the space thus rescued; retrofitting of office, commercial, and apartment buildings to let them be naturally ventilated when weather permits; mandating that all new construction be designed for non-air-conditioned comfort at times of he year when it's achievable; and many other changes.

It won't be easy. Reducing the toll of death and illness in summers to come will require a total transformation of urban landscapes and socioeconomic relations, but it will also require drastic, permanent reductions in greenhouse emissions.

It will mean international agreements imposing ironclad barrel-and-ton ceilings on global extraction of fossil fuels and other minerals. Specific extraction, import, and export ceilings must be adjusted in accord with each country's domestic endowment of resources, taking into account per-capita requirements for good quality of life.

An impermeable ceiling with no offsets or other escape hatches will mean that accustomed volumes of production, consumption, and wealth generation will no longer be possible in wealthier nations, while a solid floor can make possible a better life for resource-poor populations.

That's the only real way to beat the heat.

Stan Cox is the author of Losing Our Cool: Uncomfortable Truths About Our Air-Conditioned World. With Paul Cox, he is co-author of How the World Breaks: Life in Catastrophe's Path, From the Caribbean to Siberia, published this summer.