- Increasing temperatures pose severe risks to human health.
- Researchers are exploring the limits of human endurance without air conditioning.
- Heat waves are causing numerous fatalities.
- Argophilia journalists will investigate the issue next week.
Understanding Human Limits in Extreme Heat
Record-breaking heat waves have plagued the U.S. this summer, with at least 38 heat-related fatalities reported. As climate change drives rising temperatures, researchers strive to understand how high temperatures can climb before becoming unsurvivable without air conditioning. Experts are concerned about regions lacking reliable cooling systems, potentially facing mass casualties.
The human body cannot handle a core temperature of 43 degrees Celsius (109.4 degrees Fahrenheit). According to Jennifer Vanos, an associate professor in the School of Sustainability at Arizona State University, reaching this temperature means almost certain death for 99.9% of people. Heat tends to kill more subtly by aggravating existing health problems like cardiovascular or renal diseases.
The Role of Humidity
Sweating helps regulate body temperature by releasing heat. However, excessive humidity hampers this process. Scott Denning, a climate scientist at Colorado State University, explains that when it’s too humid, sweat doesn’t evaporate, preventing the skin from cooling down. This causes metabolic heat to build up, resulting in high fever, heat stroke, and potentially death.
Factors to Consider:
- Age: Older individuals have reduced sweating capability, making them more vulnerable
- Climate: Dry regions can exacerbate heat stress
- Humidity: High humidity levels impair the body’s natural cooling mechanism
The human body cannot endure a core temperature of 43 degrees Celsius (109.4 degrees Fahrenheit). According to Jennifer Vanos, an expert from Arizona State University, nearly everyone reaching this temperature would not survive. Heat doesn’t only lead to death; it often exacerbates existing conditions like heart and kidney diseases.
- The body cools itself by sweating.
- Excessive humidity hampers sweat evaporation.
- A wet-bulb temperature above the body’s internal temperature prevents heat dissipation.
The Critical Threshold
A 2010 study established a wet-bulb temperature of 35 degrees Celsius (95 degrees Fahrenheit) as the limit for human adaptability without cooling. However, this measure does not consider sun exposure, clothing, and physical activity. A 2020 study found that regions such as coastal India, Pakistan, and the Persian Gulf nearly reached this dangerous wet-bulb threshold, sparking worries about high mortality rates.
- Sun exposure and physical activity impact survivability.
- Wet-bulb temperature measures the cooling effect of sweat evaporation.
In Crete, the influx of tourists is causing unrest among residents. Popular spots brace for record numbers this summer, while locals demand lower rents and fairer distribution of resources.
Economic Impact vs. Local Benefits
Tourism is a significant income source across Europe, estimated to contribute about 10% to the EU’s GDP and employ around 12.3 million people.
- Income Disparities:
- Many locals don’t benefit from tourism revenue
- Rents increase, properties become unaffordable
- Restaurant prices cater to tourists
- Minimum Wage Disparities:
- Portugal: €4.85/hour
- Spain: €6.87/hour
- Italy: No minimum wage
Questions arise over where the tourism money goes. Large portions benefit airlines, hotel chains, international companies, and the cruise industry. Locals bear the burden of pollution and resource consumption, fueling tensions.
Policies, Protests, and Future Directions
European cities are taking steps to manage tourism’s impact.
- Amsterdam:
- Ban on new hotel construction
- Demarketing campaigns target party and drug tourism
- Lisbon and Palma de Mallorca:
- Halt on issuing new Airbnb licenses
- Time limits on tourist rentals
- Barcelona:
- Renting out 10,000 holiday flats to expire by 2028
- Addressing a 60% rise in rents over the past decade
- Cruise Ship Restrictions:
- Venice banned large ships since 2021
- Amsterdam to introduce restrictions by 2026
The shift towards promoting “high-quality” tourism is controversial. Some argue it may increase inequalities. The focus on attracting wealthier tourists could lead to higher water consumption, increased property purchases, and real estate speculation, directly impacting locals’ lives.
Revising Survival Estimates
New research indicates that the perceived upper limits for heat tolerance were overly optimistic. A 2022 study in the Journal of Applied Physiology suggests that young, healthy individuals may struggle at wet-bulb temperatures of 30-31 degrees Celsius (86-87.8 degrees Fahrenheit) during basic activities. Older adults, particularly those in dry climates, are at even greater risk.
Vanos’ research, published in Nature Communications, highlights the vulnerability of older adults. These individuals can endure temperatures above 115 degrees Fahrenheit for up to six hours, even in low humidity and shade. Since older people sweat less, they face a significant threat from extreme heat.
- Survival thresholds vary by age and health.
- Older adults can’t sweat as efficiently, increasing their risk.
Ongoing Investigations
Next week, Argophilia’s journey will explore how extreme heat impacts various populations and the measures necessary for survival. Their findings will further illuminate the severe risks posed by rising temperatures.
Understanding how humans react to extreme heat is crucial as global temperatures climb. Different populations, especially older people, face varying risks. Further research and proactive measures can improve survival rates even as the planet warms.
