Fans may not keep older adults cool during heat waves

In a small study of older adults experiencing extreme heat, electric fans didn't reduce core body temperature

Air blowing from an electric fan alone isn’t enough to cool off older adults sweltering indoors in a heat wave, new research shows. A study of 18 adults aged 65 to 72, monitored in a controlled-climate chamber simulating extreme heat wave conditions, found little difference in peak core temperatures as a result of electric fan use, scientists report October 17 in the Journal of the American Medical Association.

Older adults, many of whom prefer to weather heat waves their own homes, are particularly at risk for heat-related health impacts. In the absence of access to air conditioning, using pedestal-style electric fans has been one recommended strategy for individuals at home to try to stay cool. Fans can speed up heat loss, lowering the body’s core temperature, by increasing sweat evaporation.

But recent studies based on biophysical models have suggested that fans may not provide much cooling as the ambient temperature tops 33° Celsius (91° Fahrenheit) — particularly for older adults who may not sweat as efficiently.

So environmental physiologist Fergus O’Connor, now at Griffith University in Brisbane, Australia, and colleagues decided to directly test fans’ cooling power during heat wave conditions. Study participants spent three episodes of eight hours each sitting in a chamber at the University of Ottawa, with the temperature set at 36° C (96.8° F) and 45 percent relative humidity. Those conditions are similar to the climate Vancouver citizens endured during the weeklong heat dome that settled over British Columbia in 2021, which led to an estimated 619 deaths in the province.

The climate-controlled chamber also had an electric fan. Previous models simulating fan effectiveness assumed a pretty powerful airflow of around 3.5 to 4.5 meters per second. But that’s more power than many standard home fans are capable of, the researchers note. So each exposure period included a different fan speed: no airflow, a slow airflow of 2 meters per second and a fast airflow of 4 meters per second.

The team then evaluated the subjects’ body core temperature, cardiovascular strain, dehydration level and thermal comfort — the perception of feeling too hot or cold. The findings suggested that, compared to the control case of no fan airflow at all, the slower airflow resulted in no significant changes in core temperature, blood pressure, fluid consumption or thermal comfort. The faster airflow improved perceptions of thermal comfort — but, biophysically speaking, there was no significant improvement. 

Source: Science News

Climate change made 2024 the hottest year on record.

Scorching temperatures across the world set troubling new records. This is what it felt like  

Over and over, the numbers tell the same story: 2024 was Earth’s hottest year on record, knocking the previous record holder 2023 out of the top spot.

But temperatures alone can’t describe the human cost: humidity that challenges the body’s ability to cool itself; nighttime temps that rob people of sleep; power outages; wildfire smoke; ruined crops; rising cases of mosquito-borne disease.

Meanwhile, record-breaking water temperatures in the Atlantic Ocean and the Gulf of Mexico fueled hurricanes Helene and Milton. Helene’s torrential rains caused flooding across six states in the U.S. Southeast, killing over 200 people.

Other parts of the world have their own stories to tell about the impact of 2024’s extreme heat. Here are some of those accounts.

1 PHOENIX | May–September Arizona’s capital experienced 113 straight days of daytime temperatures topping 100° Fahrenheit, with hundreds of heat-related deaths recorded. Phoenix has one of the world’s largest urban heat-island magnitudes: City temperatures are about 12 degrees higher than those in surrounding rural areas.

2 MEXICO CITY | May–June An extreme heat wave, on top of an extended drought, caused blackouts and was linked to over 120 deaths. The resulting water scarcity raised fears that North America’s largest metropolis was just weeks from Day Zero — a theoretical day when the region would run out of water.

3 SÃO PAULO | August–September Extreme heat in the Southern Hemisphere’s winter plus prolonged drought fueled wildfires in Brazil’s Amazon rainforest. Fine particles in São Paulo’s air were 14 times the World Health Organization’s recommended limit, causing the city to be ranked as the world’s most polluted for four consecutive days, from September 9 to September 12.

4 RIO DE JANEIRO | March During a heat wave in Brazil, the maximum measured temperature reached 107.6° F. But it felt even hotter. The heat index — a measurement that also includes humidity — soared to a record 144.1° F, testing the limits of humans’ heat tolerance.

5 PARIS | July–August Temperatures during the Olympics may not have broken records, but they were still scorching. Without climate change, Paris would have been about 5 degrees cooler, researchers determined. That made the Games more dangerous for athletes. Europe is the world’s fastest-warming continent, heating at a rate twice the global average.

6 LONGYEARBYEN | July–August August temps in the world’s northernmost settlement, on Norway’s Spitsbergen Island, were the highest ever recorded for that month, soaring to 68° F — more than 3 degrees higher than the previous record, set in 1997. In July, ice caps there broke the all-time record for daily melting, losing ice at a rate five times the norm.

7 BAMAKO | February–April Heat waves across West Africa’s Sahel region caused power cuts and spikes in hospital admissions. From April 1 to April 4, a hospital in Mali’s capital recorded a total of 102 deaths; the previous year, the hospital noted 130 deaths for all of April. Climate change amped up daytime highs by 2.7 degrees and kept nights 3.6 degrees warmer than usual.

8 GAZA | April A three-day heat wave exacerbated the humanitarian crisis in Palestine. Nearly 2 million displaced people in refugee camps and overcrowded shelters lacked protection from the heat and faced water and food shortages, power outages, limited access to health care and spikes in waterborne diseases.

9 DELHI | May–June India’s capital territory endured 40 straight days of daytime highs reaching 104° F, with a new record set on May 28 of 121.8° F. The unrelenting heat killed over 100 people, the nonprofit organization HeatWatch India estimates.

10 MANILA | April The Philippines’ megalopolis of over 14 million people sweltered through a deadly 15-day heat wave, an event that would have been impossible without climate change. The heat brought water shortages, crop losses and school closures.

11 EAST ANTARCTICA | July At winter’s peak, temperatures across a big chunk of the continent hovered at –4° F, about 50 degrees higher than normal. The event was the largest temperature anomaly anywhere this year.

Source: Science News December

How Global Trade Is Shifting as the World’s Population Ages

A demographic alarm bell is ringing in Japan, where the birthrate fell last year to its lowest point in recorded history. The sharp drop in births from the previous year marks the eighth consecutive year of decline. Former Prime Minister Fumio Kishida labeled this demographic crisis Japan’s greatest challenge. But this is more than just Japan’s story.

The world is aging, fast. As it does, global trade will shift in unexpected ways. Japan offers a preview of what much of the world will soon face, as economies everywhere start to see record-low birthrates. South Korea recently recorded the lowest birthrate globally, while Italy hasn’t seen an increase in births since 2008. And this is no longer just a challenge for wealthy, industrialized countries.

In Latin America and South Asia, the population ages 65 and older is quickly rising. Life expectancy is rising even as fewer people are being born. The result: Nearly 1 in 4 people worldwide will be 65 or older by century’s end. That shift could reshape the world in ways we’re only beginning to understand.

Countries are scrambling to adapt to the financial strain of aging populations.

Germany has raised the retirement age, a move echoed across Europe. Greece has introduced a controversial six-day workweek, while China, reversing its one-child policy, now urges families to have three children. Japan is turning to automation to fill the gaps left by retiring workers, and is bringing in more migrant workers.

Amid these shifts, Africa’s youthful population remains a demographic outlier, with over half of its population younger than 25 years old. As economies age, they may experience a decline in overall production and consumption. With fewer workers available, production is likely to move away from labor-intensive to more capital-intensive industries, making capital productivity crucial for sustaining output and growth.

The “consumption- retirement puzzle” adds uncertainty to consumption patterns. While traditional theories suggest consumption remains steady throughout life, in reality, some retirees may spend less due to insufficient savings, shifting their focus to essentials. In aging economies, consumption is moving toward goods and services that cater to an older population. Industrial equipment, transport, and work-related expenditures are giving way to increased spending on healthcare and other essentials for seniors.

In Japan, for example, demand for strollers and baby diapers has plummeted while demand for adult diapers has surged. Similar patterns are emerging globally. In China, spending on medical care and food is rising, while expenditures on transportation, household durables, and recreation are declining with age.

Simulations done by economists Sagiri Kitao and Tomoaki Yamada for Japan through 2050 suggest consumption will fall across the board as the population continues to age, with nondurable goods declining the slowest. The U.S. and Singapore are following a similar trajectory, reflecting a broader global realignment in consumption driven by demographic changes.

As populations age, changes in consumption and labor supply will reshape the structure of global trade, though the full impact isn’t yet understood and depends on the import content of consumption. Some studies hint that older economies might altogether trade less, focusing instead on more capital-intensive goods, while the aging workforce may change the skills used in producing traded commodities. Impacts on trade composition, however, remain an open question. Industrial and durable goods are among the top import and export categories globally.

We can expect these categories to shrink as work-related expenditures decline. Similarly, as birthrates fall and fewer children are born, the global market for toys, infant products, and sports equipment may contract. Such imports are already declining in countries with a higher average age, such as Japan. However, these trends are suggestive, as reduced imports could potentially be offset by increased domestic production.

Conversely, we can anticipate an increase in the trade of services, particularly in areas like healthcare and eldercare. Medical services, provided remotely or through medical tourism, will likely become a more significant component of global trade. Japan’s digital health industry is already growing fast. Its telemedicine market is expected to reach $404.5 million by 2025 (due to “shortages in medical specialists”), and broader healthcare IT, including wearable tech and online monitoring, is projected to hit $16 billion.

The changing demographics suggest a major transformation in global trade. And as the goods and services exchanged shift, there will be opportunities for countries to change their standing in global trade. For younger, less industrialized African economies, the challenge is to leverage their demographic advantage and pivot toward sectors that can thrive in a world less reliant on industrial goods.

Traditional paths to higher-income status, like export-driven industrialization, may lose their effectiveness in an aging global economy with diminishing demand for such products. Wealthier nations will need to delay retirements, rely on migrant labor, and invest in technology to sustain productivity.

Developing nations with aging populations face challenges without access to new technologies, potentially relying on older workers for longer. Addressing this demographic shift will deeply affect markets, production, and trade. It will also demand unprecedented global coordination to ensure that the world can produce and afford what it needs, with no one—and not a single country—left behind.

Source: Barrons