Our bodies cool us down by sweating because water requires a significant amount of energy to change state from liquid to gas, making it an ideal medium for carrying thermal energy away from our bodies.

13 unconventional ways to stay cool during heat waves

While air conditioning is the default solution for many in a heat wave, it can get expensive while requiring the consumption of fossil fuel energy. So, how else can you stay cool during a heat wave? This list compiles some practical, at times quirky, suggestions, including an ice-pack-filled aubergine hat.

Heatstroke is when the body's core temperature becomes dangerously high—and needs to cool

Warning signs that the body is overheating include rapid breathing, cramps, heavy sweating, nausea, and feeling lightheaded. Drinking plenty of fluids, seeking shade, and cooling the body down as quickly as possible with icepacks can help reduce the risk of heatstroke.

Data centers can be kept cool by circulating fluid over plates atop high-temperature components or by submerging equipment in non-corrosive oil that does not conduct electricity.

Heatstroke treatment guidelines were built almost exclusively on research in men

Protocols for the standard treatment recommendation for heatstroke—whole-body cold water immersion—were built based on studies almost entirely in men. The research wasn't replicated in women, who typically cool faster than men during cold water immersion, raising questions about standard protocol safety for women, due to the risk of overcooling.

Heatstroke is sometimes missed because the patient is really sweaty

Since the condition involves losing the ability to cool oneself, clinicians sometimes see someone who has exertional heatstroke—like a high school athlete who is really sweaty—and don't realize the heat-related illness has already progressed to heatstroke. Classic heatstroke typically occurs among the very young or the elderly. (Some users may encounter a paywall.)

Data centers require interconnected server- and building-level cooling systems

Computer equipment can be cooled by circulating cold air or water through the equipment racks, siphoning the heated fluid into a heat exchanger. This exchanger transfers thermal energy to building cooling systems, which can dispose of the heat by evaporative cooling—the way humans cool off by sweating—or via air conditioning.

Heatstroke occurs when the body reaches 104°F or higher and can't cool itself

Untreated, this medical emergency can result in permanent disability or death. Someone suffering from heatstroke—defined as a core temperature of 104 degrees Fahrenheit but sometimes as high as 106 degrees Fahrenheit—may appear confused and require immediate cooling, ideally with an ice bath.

Watch a server submerged in a fluid continue to run and stay cool by boiling the liquid away.

Exertional heatstroke is a top killer of athletes and soldiers-in-training

Often characterized by collapsing while exercising in the heat with intense sweating, this type of heatstroke among otherwise healthy people occurs when the body loses the ability to cool itself during intense exercise and the body's core temperature has risen to 104 degrees Fahrenheit or higher and cannot cool itself. If treated quickly, it's often survivable, though it can cause lasting damage.

Heatstroke—from overexertion or extreme heat—drives core body temperature to 104 degrees Fahrenheit or higher, setting off a cascade of problems in the body.

Certain medications that affect blood flow or mood boost the risk of heatstroke

Drugs that narrow blood vessels, beta blockers that regulate blood pressure, diuretics, antidepressants, and antipsychotics can all affect the body's ability to regulate its internal body temperature, and so individuals taking these medications need to take special care in extreme heat and when exercising in hot conditions.

Reduced inflammation from cold plunges lacks scientific support

The cold water triggers immediate cold shock, increasing heart rate and blood pressure, and prolonged exposure can lead to cold-water incapacitation and hypothermia. Plungers are encouraged to enter the water slowly and manage their breathing to reduce the risk of shock. Warm baths post-plunge are discouraged, and exercise is generally better for recovery.

Scalp cooling caps may help prevent hair loss during chemotherapy by temporarily reducing blood flow to the scalp, thereby reducing the amount of chemotherapy that reaches hair follicles.

Extreme heat puts people at risk of developing kidney stones

It's essential to remain hydrated in summer weather to keep your body healthy, but one reason is to help dilute minerals that naturally build up if they aren't excreted in our water-fueled urine. Doctors recommend people generally drink 64 ounces of water a day and also eat foods with salt to help ward off dehydration.

Legionnaires' disease is a serious lung infection caused by Legionella bacteria, and it's often contracted from inhaling contaminated mist or water.

Some data shows cold showers can help with depression

An icy water exposure can lead to the release of norepinephrine, cortisol, dopamine, and other stress hormones that are beneficial, among other potential effects. Some data shows that this type of exposure can help combat depression symptoms among some patients, but more research is still needed. (Some users may encounter a paywall.)

Feels-like temperature indicates how our skin will feel

When the wind is moving faster, we tend to feel colder due to the so-called "wind chill," which cools our bodies by moving heat away from them and making water evaporate faster. On the other hand, high levels of humidity can make us feel 10 degrees warmer at times.

Wind chill speeds up the loss of heat from the body

During cold weather conditions, strong winds against exposed skin can produce a sensation of temperature colder than the surrounding air temperature. The accelerated loss of body heat increases the risk of frostbite and hypothermia, with frostbite able to set in as quickly as five minutes.

Since 2022, two-thirds of data centers have been built in water-stressed areas

In residential evaporative cooling systems, 10% of consumed water is lost to evaporation compared to 80% in data centers. Although some companies have pledged to become water-positive—replenishing more freshwater than they consume—by 2030 through a transition to air cooling, only 10% of data center operators track water use across all their facilities.

Korey Stringer, of the Minnesota Vikings, died of heat-related illness in 2001

In response, the NFL overhauled its heat approach and no other player has since died from heat-related illness. Even at the high school level, research suggests safety measures should include: mandating water breaks, keeping a cool tub available, and having athletes acclimate to high-temperature playing conditions for a week or longer before donning the full set of protective equipment.

Thermodynamics makes building data centers in space to cool equipment impractical

Rather than cooling via interactions with flowing cold air or water, data centers in space would dissipate energy primarily by radiation, in which an object at any temperature above absolute zero emits light. This method is much less efficient at cooling and would require hyperscale data centers to have radiator panels thousands of times larger than those on the International Space Station.

Heat exhaustion is the most likely diagnosis if someone is talking clearly

Heatstroke, true to its name, looks more like a stroke. Its symptoms include severe disorientation, irritability, and seizures, among others. A patient does not need to have collapsed in order to have exertional heatstroke, but if someone is talking clearly, they likely have heat exhaustion, and it hasn't progressed to heatstroke.

Water vapor is used to manage heat in high-end smartphones

While smartphones have traditionally been cooled using a highly conductive plate that dissipates heat from the chip, vapor chambers offer a higher heat-removal capacity. This technology has been utilized in laptops for decades to absorb heat by cycling a fluid between liquid and gaseous phases.

Watch the cumbersome, but necessary, precautions healthcare workers must take to care for and protect themselves while caring for Ebola patients.

Schizophrenia increases heat death risks in several complex ways

Evidence shows that people with schizophrenia have an inherently harder time regulating internal body temperatures. They may also struggle to find safe shelter during extreme heat, and their prescribed antipsychotic medications often have dehydrating effects, collectively elevating the risk of heat-related illness and death, as illustrated by this article that focuses on the final days of Stephan Goodwin's life in 2022. (Some users may encounter a paywall.)

How to survive hypothermia

Hypothermia is a deadly risk for those living in cold areas, causing around 1,500 deaths a year in the United States. Stay safe with tips from this article, which cites research papers to help prevent and treat the condition. Take note of the best fabric to wear when cold weather hits—not cotton but wool.

Heat pumps use an easily boilable chemical to regulate temperature

In air conditioners, warm air is pulled from a home to turn a refrigerant into a gas, which is then compressed, raising its temperature. The gas naturally releases this energy to the comparatively cooler environment when exposed, then expands and is reused in the system. Heaters run in reverse, with the refrigerant picking up energy from the comparatively warmer environment.

Cold water swimming can induce positive stress

The tradition of cold water swimming (or taking a cold plunge, or even a cold shower) has been shown to release the same hormones triggered during a stress response. This can have the effect of increasing blood flow, improved mental acuity, and more.

Some materials can absorb low-energy light and emit high-energy radiation

Through anti-Stokes cooling, incoming energy is combined with vibrations in a material's crystal lattice to produce a net reduction in its temperature. Using this effect, lasers can be directed at microchip hot spots to help keep data centers cool.

Cooling each square foot of a room requires at least 20 BTUs of capacity

British thermal units describe the cooling capacity of air conditioners, though noise levels, directional airflow, and filtration also affect their effectiveness. Insufficient BTUs are unlikely to cool a large enough room faster than the environment warms the air.

67 US high school athletes died from exertional heatstroke between 1982 and 2022

Many of those deaths were from football specifically, where student athletes play in hot conditions while wearing heavy protective gear. Few states mandate heat guidelines for school athletes, and this article says that's of increasing concern with more high heat index days.

Most fungal pathogens can't survive the heat of our bodies.

When users prompt AI chatbots, both cooling systems that support data centers and power plants that rely on steam cycles to generate electricity for data centers contribute to water use.

Normal body temperature varies from one person to another; it's not uniformly 98.6 F, as physician Carl Wunderlich determined in the 1800s.

Cold-blooded reptiles seek heat, and that behavior may help combat fungal infections

This Radiolab podcast episode takes on the idea that though our human bodies are too warm for the majority of fungal species to effectively replicate inside our bodies, that's not the case for reptiles. Yet when those species warm their bodies by basking in the sun on rocks, they can soak up heat and may also help keep fungal infections in check.

Heatstroke deaths may be massively undercounted—perhaps by a factor of 10

One often-cited average estimate of annual American heat deaths—roughly 1,200 per year—is based on death certificate data, but it may be a significant undercount because heat kills through cardiovascular, kidney, and respiratory causes that are more likely to be cited on those documents. (Separate analysis that looked at data from 1999 to 2023 found that the highest number, in 2023, was 2325.)