A smarter alternative that is being adopted across a dozen American cities, including Atlanta, Boston and Dallas, is to change surfaces to enable an element of cooling. City roofs and roads absorb more than 80% of incoming sunlight, contributing three times more to city heat than does global warming. The solution is to treat all city surfaces as a single integrated solution to heat. With our help, last year Atlanta adopted a bill requiring new and retrofitted roofs to be much more reflective. This one measure, one of several the city is embracing, will triple the reflectivity of commercial roofs, cool the city by 1.30C (with up to 3.50C cooling in hot, lower-income neighbourhoods) and cut the electricity bill by $310m. Putting these mandates in place costs a city nothing, and because reflective roofs cost about the same as dark roofs, businesses and consumers also reap benefits. Greg KatsChief executiveSmart Surfaces CoalitionWashington, DC The American Sunbelt would not be thriving without the introduction of air- conditioning. Growing up in Mississippi in the 1950s, our summers were unbearably hot and humid. With no AC cities like Atlanta, Charlotte, Houston and Phoenix would not be thriving. The migration from the northern blue states to the southern red states would not be happening without AC. James HortonCharlotte, North Carolina Your article on the deaths and cover-ups in Britain’s maternity hospitals identified a crucial paradox but stopped short of its lesson (“The lying doctors”, July 4th). You noted that reports by staff of moderate-harm incidents in Nottingham fell after the “duty of candour” was introduced in 2014. So consequently, a rule that was intended to elicit honesty produced dishonesty instead. This is not an anomaly. It is a predictable factor in complex systems. Behaviour changes when disclosure is mandated. When staff fear blame, litigation and sanction, it is the categorisation of harm that changes rather than practice. Safety depends on learning, and learning depends on honest accounts of fallibility. People give such accounts only when it cannot be turned against them. That is why investigations by the Health Services
Safety Investigations Body carry a statutory “safe space”, as do equivalent regimes in aviation. You concluded that truth cannot be legislated and that rotten leaders must go. Accountability to the harmed families is indeed non-negotiable. But every inquiry you list, from Morecambe Bay onwards, removed leaders; none changed the conditions under which truth is told. Until learning is formally separated from enforcement, each new leadership will inherit the same incentives, and further reports into patient-safety failures will follow. Ted BakerChairHealth Services Safety Investigations BodyLondon Your article on photobiomodulation (PBM), therapies that use red and infrared light as the agent, made a distinction between promising clinical evidence and more speculative wellness claims (”The surprising benefits of red light”, July 25th). Clinical adoption has already outpaced the public conversation. In the United States, PBM-related procedures are now performed at more than 2,300 sites of care. Among the highest-volume facilities, the number of procedures have risen by roughly a third, with recent quarters exceeding 1,000 procedures at a single site. The clinicians involved span orthopedic surgery, neurology, physical therapy, chiropractic services and rehabilitation. That sharpens your conclusion. The unresolved questions that Professor Glen Jeffery raises—wavelength, dosage, distance and duration—are no longer purely academic. They are being confronted in thousands of clinics every week. If PBM is to fulfil its potential in areas such as diabetic glucose regulation, retinal aging and traumatic brain injury, the development of standardised treatment protocols will need to keep pace with its growing clinical adoption. Aalap PatelVice-president, go-to-marketAcuityMDPrinceton, New Jersey If cities want to boost their night-time economies they would be best to avoid “making it easier to party” by providing more alcohol licences (“The night shift”, July 18th). The higher margins and tax revenues from alcohol are tempting, but as a former police officer, I know that easier access to
drink comes at a heavy price: domestic violence, drunk driving, addiction and soaring health-care costs. Anyway, evidence suggests that young people are souring on traditional drinking culture. What cities truly lack are places for proper late-night conversation and relaxation, such as cafés, extended-hour libraries and museums and game lounges. People want a place where they can connect with others without the pressure to drink. Vibrant alternatives already flourish in Middle Eastern café culture and East Asian night markets. Paris hosts bakery raves and Berlin has “Sober Sensations” events. People still want a night out. They just don’t want to stumble home at 4am covered in sick. Charles HoltsclawHouston There is one city in America that takes up your prescription of letting people have fun: New Orleans. As Bob Dylan once said: “Everything in New Orleans is a good idea.” Morris ZwickGermantown, Maryland
Andy Burnham’s view of British music is oblivious both to the breadth of music being produced in Britain today and to the country’s musical history beyond the familiar canon of 1980s indie bands (Bagehot, August 1st). He overlooks Manchester’s, and Britain’s, rich, black musical heritage. Rather than repeating the same established names like The Smiths and Oasis, he might acknowledge figures such as DJ Paulette, Hewan Clarke and A Guy Called Gerald, who helped shape Manchester’s dance and electronic-music culture, as well as the broader, now-mythologised and often whitewashed story of the Hacienda, a music venue. Overall, the prime minister could learn from contemporary groups such as London’s Ezra Collective, whose work champions inclusion and hope, rather than celebrating worn-out indie anthems. We need less “Wonderwall” and more “Where I’m Meant to Be”. Tim PunterLondon The Big Mac index does indeed naturally invite a lot of puns (“40 years of burgernomics”, August 1st). Although some people may have a beef with such punnery, for me they are the special sauce of the index. Lettuce not dwell on how cheesy they can be; trying to remove them would leave the Big Mac index in a real pickle. Indeed, not allowing journalists to leave onion-like layers of puns throughout their articles would be a real pain in the bun. Paul ShrinerAnkeny, Iowa This article was downloaded by zlibrary from https://www.economist.com/letters/2026/08/13/does-air-conditioning-contribute-to- urban-heat
The case for overhauling American science The focus should be on harnessing AI and out-competing China, writes Michael Kratsios, the White House science chief Aug 13th 2026 AS THE SECOND world war drew to a close, President Franklin D. Roosevelt tasked his science adviser, Vannevar Bush, with reorganising America’s scientific enterprise for a post-war order. Bush’s answer, a report entitled “Science: The Endless Frontier”, became the blueprint for American government support of basic science. In turn this led to the creation of the National Science Foundation (NSF), a federal agency that supports fundamental research, and shaped the triumphal attitude to science and technology that defined so much of the “American Century”. The belief that government should support basic research, that this research can be a foundation of national prosperity and that America can organise its
scientific institutions to facilitate that process, remains as true today as when Bush laid out that schema. But I believe Bush would be the first to recognise that the world in which science is conducted has changed dramatically since 1945, leaving the American research system in need of an update. Bush wrote his report to Roosevelt at an exceptional moment. America stood on the cusp of final victory in the largest conflict in human history. The countries of Europe, the previous century’s scientific powers, lay mostly devastated. This structural reality produced the heights of American manufacturing power. Similarly, it explains part of Bush’s success in continuing wartime organised science in peacetime. In 1961 President Dwight Eisenhower described the cold-war culmination of Bush’s initiative. Eisenhower observed that “research has become central” and “more formalized, complex, and costly”, as “task forces of scientists in laboratories and testing fields” displaced the “solitary inventor”. Mass industrial science soon mobilised government, corporations and academia to beat the Soviet Union to the Moon. That post-war industrial America no longer exists. And the dreams of an open world that followed the cold war have given way to a competitive global environment, in which Chinese technical capacity, not Soviet science, seeks to overtake America in a race for scientific and technological leadership. There are reasons besides the procession of history to think the “Endless Frontier” is out of date. In recent decades American scientific enterprise has shown its age, with diminishing returns. Despite biomedical research budgets soaring since the 1990s, the rate of significant breakthroughs has slowed and drug approvals have plateaued. Many scientists spend nearly half their time on paperwork. The system serves itself better than its scientists. Bush’s managerialism promoted what was later termed the “linear model” of scientific development, in which government funds basic research in universities, and industry turns newly published insights into novel applications. This made sense when government was the primary administrator of fundamental science. But these days an increasing number of scientists do their research in industry, and industry funds an increasing