Time to be proactive about preparing for extreme heat events!
These recent global heatwaves have reignited the debate about how we can protect people from rising temperatures – and how high we can stand them to go. But the headline figures do not give the whole story when it comes to the impact of high temperatures on humans, because humidity, which is not factored into these figures, plays a huge role in how we actually experience heat.
Recent research has found that we may actually already be nearing the threshold values for human survivability of temperature and humidity for short periods in some places of the world – a measure known as the “wet-bulb” temperature – and that this threshold may actually be far lower than previously thought. Wet-bulb conditions occur when relative humidity is above 95% and temperatures are at least 31.1°C (88°F), or, a wet-bulb temperature of 35°C (95°F).Air conditioning removes humidity from the air and is the best solution when wet-bulb temperatures get too high. Fans can help sweat evaporate more efficiently, but they're less effective. Raymond noted that people die of heat stress at wet-bulb temperatures much lower than 95 degrees Fahrenheit (35 degrees Celsius).What is the danger zone for wet bulb temperature?
The upper limit that humans could withstand was thought to be 95 F at 100% humidity, according to a 2010 study. New research out of Penn State University's Noll Laboratory found that the critical limit is in fact even lower – 88 F at 100% humidity.
As people age, our bodies are less able to compensate for the effects of certain environmental hazards, such as air pollution. Older adults are more likely to have health conditions that make them more sensitive to climate hazards like heat and air pollution, which can worsen their existing illnesses. A sustained wet-bulb temperature exceeding 35 °C (95 °F) is likely to be fatal even to fit and healthy people, unclothed in the shade next to a fan; at this temperature human bodies switch from shedding heat to the environment, to gaining heat from it. Humans, like most mammals, cool themselves through sweating. Body heat is used to convert sweat into water vapor, and as that evaporation process occurs, the body cools.
No matter what race or complexion you are excessive heat is dangerous to you and your continued well being. While dark skin is better protected from ultraviolet radiation, it does absorb more of the energy in visible light than light skin. But most of the sun's heat comes in invisible infrared radiation. Dark and light skin are the same color in that range. Dark skin absorbs no more heat than light skin does. researchers have found that the racial disparities in relation to climate related deaths are directly caused by lack of access to air conditioning or the energy or finances to keep air conditioners on during extreme heat events!
Blacks and Hispanics have also been shown to experience greater adverse mental health-related outcomes (e.g., anxiety, psychosis, and substance use disorders), as measured by ED visits and self-reported symptoms, associated with temperature (heat and cold) as compared to Whites. Temperature has been linked to new onset or exacerbation of mental disorders, and people with a mental illness are also at higher risk for heat-related illness due to underlying physical pathologies (e.g., irregular thermoregulation related to schizophrenia); inability to adapt and cope with changing temperatures; or effects of psychiatric drugs on thermoregulation
"It's a very effective means of cooling, but it's crucial that the sweat can actually evaporate," said Tapio Schneider, a professor of environmental science and engineering at the California Institute of Technology. When the wet-bulb temperature, or the combination of heat and humidity, exceeds the temperature of the human body — around 97 degrees Fahrenheit or 36 degrees Celsius — sweat cannot evaporate and humans can no longer cool themselves down.
“It’s really a hard limit for survivability,” Schneider said. “You can die just by sitting there. You don’t need to move or do anything else. There’s simply no way to cool and you overheat.” Climate studies have found that as global temperatures creep up, warmer air will be able to hold more moisture. That, in turn, will increase humidity and cause wet-bulb temperatures to rise. A study published in May 2020 in the journal Science Advances found that heat and humidity in certain parts of the world are already testing the limits of human survivability. The research found that parts of South Asia, including India and Pakistan, coastal and southwestern North America and areas around the Persian Gulf have experienced conditions "nearing or beyond prolonged human physiological tolerance."
because of the life threatening conditions it is more important than ever to have access to cooling units and energy that is always accessible. This is why many Americans are adding solar power as a survival asset for climate change. The average American adding panels and a battery storage system will receive a solar tax credit value of about $7,682 for installing solar panels, based on the average solar system cost of $23,540.