The heat index reached 152 degrees in the Middle East -- nearly at the limit for human survival

[orthoclad]

Last edited Tue Jul 18, 2023, 07:32 PM - Edit history (1)

Washington Post reports extreme heat index temperatures near the Persian Gulf. The Persian Gulf airport reported a heat index temperature of 152F. The nearby Persian Gulf has water temperatures around 100F, pumping high humidity into the air, as I recently documented in https://democraticunderground.com/1127164242 .

https://www.washingtonpost.com/weather/2023/07/18/extreme-heat-record-limits-human-survival/

In recent days, China set an all-time high of nearly 126 degrees Fahrenheit, while Death Valley hit 128 degrees, two shy of the highest reliably measured temperature on Earth. Phoenix was expected to observe a record-breaking 19th consecutive day at or above 110 degrees Tuesday. And in the Middle East, the heat index reached 152 degrees, nearing — or surpassing — levels thought to be the most intense the human body can withstand.

Such conditions are more than enough to overwhelm the body’s ability to regulate its internal temperature, experts said, and offer a glimpse of dangers only expected to become more prevalent as global warming increases extremes in heat and humidity.
“We know these extreme temperatures are killing people right now,” said Cascade Tuholske, an assistant professor at Montana State University.

...

On Sunday at the Persian Gulf International Airport in Iran, air temperatures exceeded 100 degrees, and the air was nearly saturated with humidity. That translated to a wet bulb temperature of 92.7 degrees (33.7 degrees Celsius), according to data and a wet bulb conversion calculator from the National Weather Service.

The heat and humidity were so intense, they translated to a heat index value that was literally off the charts. The heat index is designed to max out at about 136 degrees, but on Sunday it surpassed 150 degrees on the Persian Gulf.

NWS wet bulb calculator is here: https://www.weather.gov/epz/wxcalc_rh

The human body cools by the evaporation of sweat. If the humidity is high, sweat evaporates poorly and doesn't carry off body heat. Wet bulb temperature, a measure of evaporative cooling, is defined by wikipedia as:

The wet-bulb temperature (WBT) is the temperature read by a thermometer covered in water-soaked (water at ambient temperature) cloth (a wet-bulb thermometer) over which air is passed.[1] At 100% relative humidity, the wet-bulb temperature is equal to the air temperature (dry-bulb temperature); at lower humidity the wet-bulb temperature is lower than dry-bulb temperature because of evaporative cooling.

The WaPo article makes the point that seaside breezes sound like they'll cool you off, but high humidity from hot offshore water, like we're seeing in Florida, Greece, Italy and the Persian Gulf, is a partner in the process of dying from heat.

For a fictional but scientifically accurate description of a wet-bulb temperature crisis in India, see Kim Stanley Robinson's Ministry For The Future. The chapter describing this event can be read here:
https://www.orbitbooks.net/orbit-excerpts/the-ministry-for-the-future/
To the best of my knowledge, the author has made this chapter available for reading. Warning: it's horrifying.