Forget #HeatIndex. #WetBulb Globe Temperature Is Where It’s At.

"One of the most common terms we hear during the summer when discussing the weather is Heat Index. While the Heat Index can give you an idea of how dangerous the heat can be, there is another lesser known variable that may give a complete description, known as the #WetBulbGlobeTemperature.

"The Heat Index is a measure of how hot it feels to the human body, taking into account the temperature and the relative humidity. The higher either one value is, the higher the heat index and the greater the stress exerted on the body. Heat Index utilizes the temperature measured in the shade and therefore will likely be greater in the sun, where many activities take place. For temperatures taken in the full sunlight, Heat Indices can increase as much as 15°F. Humidity plays a major effect on cooling the body. If the humidity is high, sweat on the surface of the skin does not evaporate as quickly, slowing the cooling of the body. If the humidity is low, sweat evaporates too fast, leading to dehydration. [See link for Heat Index chart]

"Wet Bulb Globe Temperature (#WBGT) is similar to the Heat Index in that it is an indicator of the stress on the body from the heat. While it is not as well-known as the Heat Index, it’s not a new term. WBGT was developed in the 1950s after heat related illnesses affected the US armed services during the 1940s. After its implementation, there was a reduction in heat related illnesses during basic training. One fundamental difference between the Heat Index and WBGT is that the latter is calculated with the temperature measured in the sun. While Heat Index only takes temperature and Relative Humidity into account, WBGT takes several variables into account.

These variables include:

- Temperature
- Humidity
- Wind Speed
- Sun Angle
- Cloud Cover
- Physical Activity"

Read more:
https://www.dtn.com/forget-heat-index-wet-bulb-globe-temperature-is-where-its-at/

#WetBulbTemperatures #GlobalWarming #HighHumidity #ExtremeHumidity #Heatwaves

Forget Heat Index. Wet Bulb Globe Temperature Is Where It's At.

Forget Heat Index. Wet Bulb Globe Temperature Is Where It's At. - DTN

DTN

@DoomsdaysCW KSR's "The Ministry for the Future" has a mortifying wet-bulb event in the first chapter.

Also, WBGT has been made deliberately expensive to measure, so WBT is generally used in industry. Anything over 35C WBT is considered lethal, and you can get into those regimes very easily by disregarding globe (insolation) temps.

@DoomsdaysCW

Forget Heat Index. It is marketing hype for TV.

What you want to pay attention to is the difference between temp and dew point.

When they are both the same, and high, and it is not raining, you are in a world of discomfort.

@DoomsdaysCW For anybody other than weather nerds that is not compelling. Wikipedia and NWS don't do much better.

So here's my attempt...

Wet bulb temperature is measured with a thermometer covered in a wet cloth, so it works like a person who can sweat. In dry conditions, evaporative cooling is operative, when humid, it doesn't help. So if the WBT is above body temperature a person can't cool by sweating and will die without active cooling. WBGT is a slightly fancier more accurate version.

@mcrocker TY for the clarification!
@DoomsdaysCW #WetBulb has just a few issues:
1) The name is like something from the Japanese AV industry.
2) The definition is so complex that people who aren't into #STEM can't really imagine it.
3) The conspiracy-minded redneck will tell you that it's like a sauna and you're a snowflake because he once went to a sauna and nothing happened to him.
@DqTube I would respond, "Oh, were you lifting weights in the sauna? Or picking vegetables? Then stfu!"
@DoomsdaysCW I always wondered why there’s no wind chill factor in summer.
@Virginicus The only "wind chill factor" is the one made by my fan! lol!