Quantcast
Environmental News for a Healthier Planet and Life

Help Support EcoWatch

As Climate Change Worsens, Heat-Related Deaths of Elderly Continue to Rise

Climate
As Climate Change Worsens, Heat-Related Deaths of Elderly Continue to Rise

Climate Central

By Michael D. Lemonick

The summer of 2012 isn’t even half over, and already the U.S. has been hit with two crushing heat waves, and in both cases, the searing temperatures have literally been lethal. Public health-workers know all too well that whenever the mercury soars, people die—especially the elderly, whose bodies are less resilient to stress than those of younger folks.

Climate change is only going to make things worse: as the planet warms over the coming century, climatologists project that heat waves will only get worse. That’s on top of a population that continues to age overall, expanding the number of likely victims.

The relationship between heat waves and death isn’t just speculation: it’s about as solid as any scientific finding you can name. A 2006 study by the Centers for Disease Control and Prevention, for example, showed that more than 800 people in the U.S. die from heat-related causes in an average year. When the heat is especially severe or prolonged, that rate rises dramatically. A memorable five-day heat wave in Chicago in 1995 killed more than 700, and a horrific bout of hot weather that struck Europe in 2003 caused at least 35,000 deaths.

Even without climate change, the elderly would be at risk. But research has shown that the steady buildup of heat-trapping greenhouse gases in the atmosphere means that heat waves are likely to come more often, be more intense and last longer as the century progresses. As a result, heat-related deaths will almost certainly go up, and scientists are beginning to grapple with the question of how much.

A recent report by the Natural Resources Defense Council (NRDC) estimated that by century’s end, climate change will lead to more than 150,000 extra heat-related deaths in the U.S., and a 2010 article in Environmental Health Perspectives that looked just at Chicago projected between 166 and 2,217 extra deaths every year during the last two decades of the century.

Most of these deaths, experts universally agree, will hit the elderly especially hard for several reasons. For one, the mechanisms that regulate body temperature tend to be less efficient in people over the age of 65. If the body can’t get rid of excess heat, that can ultimately lead to heat stroke, where internal temperatures can rise to a potentially lethal 105° or 106° very quickly. “If that happens,” said Francesca Dominici of the Harvard School of Public Health, a co-author of the Chicago study, in an interview, “you have to intervene immediately.”

Many older people also have chronic illnesses—cardiovascular disease, lung diseases, high blood pressure—which put the body under constant stress in any case. Add the stress of hot weather and high humidity on top of that, and the combination can lead to heart or respiratory failure. “[Epidemiologists] have really effective models for describing the relationship of heat and mortality,” said Claudia Tebaldi, a Climate Central scientist who co-authored the Chicago study.

Epidemiologists have only recently begun using these models to make climate-related projections, though. “The people studying things were originally interested in the health effects of air pollution,” Tebaldi said. Heat was only relevant insofar as it made air pollution worse—by increasing the levels of lung-irritating ozone, for example. Amidst the generally increasing awareness about climate change, the epidemiologists have now begun focusing on heat alone as a health factor. “It’s still fairly new,” Tebaldi said.

It’s also tougher to make projections for individual cities, because global climate models operate on regional, not local scales. Backward-looking studies, like one on heat-related stroke hospitalizations in Allegheny County, Pa. from 1994-2000, which will be presented at a conference in October, are straightforward, because you can just look up what the temperature was.

If you try to pinpoint future heat waves in a particular city in 2085, different climate models come up with different projections. That’s why the Chicago study points to such a wide range of potential deaths: 166 to 2,217 isn’t precise, but that’s the best the scientists could legitimately do (the NRDC study, by contrast, used just a single model to come up with very precise, but less dependable, numbers).

Dominici, Tebaldi and several colleagues recently got funding to carry out a new study that will do for other major cities what they’ve done for Chicago. Those numbers won’t be precise either, but the range should narrow in future studies as scientists use downscaling techniques to localize projections from global climate.

Hotter weather isn’t an automatic death sentence: more air conditioning and better public education can ultimately keep members high-risk groups out of harm’s way. “There are all kinds of public health interventions we can do,” Dominici said. But all of that will be costly, and given the other costs climate change is likely to impose on the U.S. economy, it will just add to the burden.

Visit EcoWatch's CLIMATE CHANGE page for more related news on this topic.

 

Sustainable t-shirts by Allbirds are made from a new, low-carbon material that uses a mineral extract from discarded snow crab shells. Jerry Buttles / Allbirds

In the age of consumption, sustainability innovations can help shift cultural habits and protect dwindling natural resources. Improvements in source materials, product durability and end-of-life disposal procedures can create consumer products that are better for the Earth throughout their lifecycles. Three recent advancements hope to make a difference.

Read More Show Less

EcoWatch Daily Newsletter

A net-casting ogre-faced spider. CBG Photography Group, Centre for Biodiversity Genomics / CC BY-SA 3.0

Just in time for Halloween, scientists at Cornell University have published some frightening research, especially if you're an insect!

The ghoulishly named ogre-faced spider can "hear" with its legs and use that ability to catch insects flying behind it, the study published in Current Biology Thursday concluded.

"Spiders are sensitive to airborne sound," Cornell professor emeritus Dr. Charles Walcott, who was not involved with the study, told the Cornell Chronicle. "That's the big message really."

The net-casting, ogre-faced spider (Deinopis spinosa) has a unique hunting strategy, as study coauthor Cornell University postdoctoral researcher Jay Stafstrom explained in a video.

They hunt only at night using a special kind of web: an A-shaped frame made from non-sticky silk that supports a fuzzy rectangle that they hold with their front forelegs and use to trap prey.

They do this in two ways. In a maneuver called a "forward strike," they pounce down on prey moving beneath them on the ground. This is enabled by their large eyes — the biggest of any spider. These eyes give them 2,000 times the night vision that we have, Science explained.

But the spiders can also perform a move called the "backward strike," Stafstrom explained, in which they reach their legs behind them and catch insects flying through the air.

"So here comes a flying bug and somehow the spider gets information on the sound direction and its distance. The spiders time the 200-millisecond leap if the fly is within its capture zone – much like an over-the-shoulder catch. The spider gets its prey. They're accurate," coauthor Ronald Hoy, the D & D Joslovitz Merksamer Professor in the Department of Neurobiology and Behavior in the College of Arts and Sciences, told the Cornell Chronicle.

What the researchers wanted to understand was how the spiders could tell what was moving behind them when they have no ears.

It isn't a question of peripheral vision. In a 2016 study, the same team blindfolded the spiders and sent them out to hunt, Science explained. This prevented the spiders from making their forward strikes, but they were still able to catch prey using the backwards strike. The researchers thought the spiders were "hearing" their prey with the sensors on the tips of their legs. All spiders have these sensors, but scientists had previously thought they were only able to detect vibrations through surfaces, not sounds in the air.

To test how well the ogre-faced spiders could actually hear, the researchers conducted a two-part experiment.

First, they inserted electrodes into removed spider legs and into the brains of intact spiders. They put the spiders and the legs into a vibration-proof booth and played sounds from two meters (approximately 6.5 feet) away. The spiders and the legs responded to sounds from 100 hertz to 10,000 hertz.

Next, they played the five sounds that had triggered the biggest response to 25 spiders in the wild and 51 spiders in the lab. More than half the spiders did the "backward strike" move when they heard sounds that have a lower frequency similar to insect wing beats. When the higher frequency sounds were played, the spiders did not move. This suggests the higher frequencies may mimic the sounds of predators like birds.

University of Cincinnati spider behavioral ecologist George Uetz told Science that the results were a "surprise" that indicated science has much to learn about spiders as a whole. Because all spiders have these receptors on their legs, it is possible that all spiders can hear. This theory was first put forward by Walcott 60 years ago, but was dismissed at the time, according to the Cornell Chronicle. But studies of other spiders have turned up further evidence since. A 2016 study found that a kind of jumping spider can pick up sonic vibrations in the air.

"We don't know diddly about spiders," Uetz told Science. "They are much more complex than people ever thought they were."

Learning more provides scientists with an opportunity to study their sensory abilities in order to improve technology like bio-sensors, directional microphones and visual processing algorithms, Stafstrom told CNN.

Hoy agreed.

"The point is any understudied, underappreciated group has fascinating lives, even a yucky spider, and we can learn something from it," he told CNN.

Trending

There are many different CBD oil brands in today's market. But, figuring out which brand is the best and which brand has the strongest oil might feel challenging and confusing. Our simple guide to the strongest CBD oils will point you in the right direction.

Read More Show Less
Financial institutions in New York state will now have to consider the climate-related risks of their planning strategies. Ramy Majouji / WikiMedia Commons

By Brett Wilkins

Regulators in New York state announced Thursday that banks and other financial services companies are expected to plan and prepare for risks posed by the climate crisis.

Read More Show Less
The left image shows the OSIRIS-REx collector head hovering over the Sample Return Capsule (SRC) after the Touch-And-Go Sample Acquisition Mechanism arm moved it into the proper position for capture. The right image shows the collector head secured onto the capture ring in the SRC. NASA / Goddard / University of Arizona / Lockheed Martin

A NASA spacecraft has successfully collected a sample from the Bennu asteroid more than 200 million miles away from Earth. The samples were safely stored and will be preserved for scientists to study after the spacecraft drops them over the Utah desert in 2023, according to the Associated Press (AP).

Read More Show Less

Support Ecowatch