Just now in the Florida Permaculture Community group, I shared this post with text & graph info from official government sources, regarding wet-bulb temperature.
A colleague (Koreen, of Our Permaculture Farm in Brooksville) commented about some of the things she is doing to keep volunteers on the farm safe from extreme heat. A lot of it involves going indoors where there is air conditioning, and using ice packs. (Koreen also makes an important point that beyond a certain wet-bulb temperature, dunking in water doesn’t always help, and can actually make things worse. I don’t know for sure but I suspect it’s related to the humidity factor. And the difficulty of water evaporating and having its cooling effect.)
Regarding her point about taking regular breaks indoors where it’s cool, I made the following comment:
Thank you Koreen. On a related note, a couple of things bear mentioning.
1) Indoors is only cooler than outdoors if you have a well-made passive-cooled house. Very rare with today’s modern industrialized houses in the USA.
Either that, or forced-air cooling. Not all people have AC available, and it is not always working, and it readily malfunctions. I read horror stories all summer every summer, and it just kills me to see people having to deal with this.
And even in cases where the mechanized forced-air cooling is not malfunctioning, a lot of people simply cannot afford the electric bill for it. I have heard of electric bills of $400 or more.
If one’s living habitat is not passively designed, and one cannot access AC, it is cooler outdoors than indoors in the summer oftentimes.
Exception would be if a house has a fully open screened porch. Unfortunately, a lot of our dwellings in Florida, even if they still have those old type of porches, previous residents have glassed them in.
I find that from about May through September, outdoors is usually cooler than indoors from about 11am to 2am at least, but not everybody has a safe spot to hang out outdoors. Yet another challenge.
(BTW I am one of the lucky few, I voluntarily do without air conditioning. I am not forced to do without it. I do without it because I dislike forced air and closed windows, and also because a core component of the mission of my house is to serve as a research station for 90% Reduction/Deep Adaptation/Degrowth -style resilience.)
2) Many people do not have a freezer that can make ice. Probably about half the rental properties I have lived in my adult life, we have not had a freezer, and/or not had one that got cold enough to actually freeze water. (I own the house that I am living in and that I share with 2 housemates, and we do have a fridge with a freezer that can freeze water. And I keep ice packs in it for emergencies such as heat exhaustion etc.)
In case the permissions get changed and the post disappears, I’m posting the basic text overview here:
Temperature/ Humidity
80 / 40% 🥵 (unpleasant; some danger)
91 / 40% ⚠️ (extreme danger)
105 / 40% ☠️ (deadly; most humans cannot survive for more than a short time)
84 / 75% 🥵
92 / 75% ⚠️
103 / 75% ☠️
34-to-36 degrees Celsius
PS. A key front of our work in reclaiming sustainable shelter, will be finding ways to retrofit existing modern homes with little “passive” mods, while remaining within city codes etc. Or else, we have to work to try to get the codes changed. And, even in rural areas, I am constantly hearing all kinds of stories about how prohibitive the codes are.
Further Exploration:
• “We Can’t Wait: How Black Neighborhoods Are Preparing for the Summer Heat” (capitalb.org): “Since the 1960s, the average number of heat waves every year across the country has more than tripled. Nationwide, the issue has led to a 900% increase in heat-related deaths compared to then. Indigenous people and Black people have experienced the worst effects. It kills more people every year than hurricanes, floods, and tornadoes — combined. … Last summer, the death certificates of more than 2,300 people in the United States mentioned the effects of excessive heat. It is the highest number in 45 years of records. As the nation’s electric grid slips into disrepair, a major issue driving these deaths is the growth in heat-induced power outages. …”