'So hot you can't breathe': Extreme heat hits the Philippines
japantimes.co.jp
japantimes.co.jp
also let's not forget that there are animals too who suffer. And thy don't have AC, water bottle, or fridge to live.
Limit was hit in 2023: https://www.washingtonpost.com/climate-environment/2024/02/0...
Because we haven't seen very many 35℃ wet bulb temperature breaches yet. The nominal air temperature is much higher than that all the time around the world, but it's only when there is very high humidity at that temp that humans start to overheat.
IIRC there have only been a few instances so far where the web bulb temp limit has been breached, e.g. some instances around the Persian Gulf, and maybe also in Mexico near the Gulf of California (not sure about the latter if it's even been breached yet, but I know it's at risk).
Edit: Wikipedia page has a list, https://en.wikipedia.org/wiki/Wet-bulb_temperature#Highest_r.... There have only been 10 recorded instances where wet bulb temp exceeded 35C.
Wet-bulb temperature is the minimum temperature you can reach by evaporative cooling (i.e., sweating). When wet-bulb temperature gets too close to core body temperature, you are physically incapable of shedding heat if you are not in air-conditioning, and how close it needs to be depends on how good health you are in.
But we actually have seen deaths in previous heat waves, which largely didn't even breach 30C wet-bulb. The 2003 European heat wave caused about 70,000 people to die, for example.
For example, at least 24500 people died from heat-related causes in Europe during heat waves of summer 2022.
And that's just one of many examples.
Highest ambient temperature ever recorded was in Death Valley in 1913.
In 1540 Europe had an extreme drought and heatwave that lasted 11 months.
I can go on and on. The 2022 heatwave wasn’t any more unusual than any other heat wave throughout history.
I posted about it before:
https://news.ycombinator.com/item?id=37455817#37459864
> You have to factor in humidity. > Scottsdale airport currently (1:40PM) is 108F (42.222C) w/ 14% humidity, meaning a wet-bulb of 71.11F (21.72778C).
> London tomorrow at noon is 86F (30C) w/ 52% humidity, meaning a wet-bulb of 72.76F (22.6444C).
> London will actually feel nastier.
the Year 2023 was the Hottest Year on Record to date globally.. each month of 2023 (edit maybe not jan-feb?) was also the hottest recorded globally. The hottest day cumulatively across the world was in 2023. The nine hottest years on record globally were the last nine years.
Please use librarianship and science skills for factual information. multiple references available for the search-impaired
Actually, I think January and February failed to breach the record--the El Nino didn't set up until April.
(But several of the later months absolutely shattered records, as did the year as a whole. 2023 as a whole breached the 2C limit).
You can't think of one pertinent home gadget that was invented between 1911 and now?
We've had one year at the level of warming that is not yet expected to yield mass death from wet bulb events.
Give it time. There's no reason to think that the current warming trend will slow, stop, or reverse itself in the near term.
Climate has changed repeatedly throughout history. Every time a temperature increase has changed to a temperature decrease, this must be preceded by the rate of temperature increase decreasing.
We observe the rate of temperature increase, continuing to increase.
Thus there is reason to believe that it will get hotter for some time, before it again gets colder.
Eh, causing it is in fact a much, much bigger industry.
These are the kind of people that had to cheat off you to pass biology yet insist that "the immune system works like this"
We'd be in serious trouble if we had a power failure triggered by a heat wave, which IIRC was a near miss in the central US heat wave last summer.
'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.'
https://en.wikipedia.org/wiki/Wet-bulb_temperature
Edit: because a high humidity means the body cannot cool anymore by sweating. A higher temperature combined with dry air is generally not a life threatening situation (if you stay in de shade and drink a lot of water).
A wet-bulb temperature of 95°F (35°C) is the theoretical limit for human survivability for up to six hours of exposure. This is equivalent to a heat index of 160°F (71°C). However, more recent research indicates that a wet-bulb temperature of 88°F can be hazardous even for young Aug 17, 2023
Understanding Wet-Bulb Temperature: The Risks of High Wet ...
https://climatecheck.com/blog/understanding-wet-bulb-tempera....
https://en.wikipedia.org/wiki/Wet-bulb_temperature
Edited to add Celsius
Edited to remove reference to shade.
(relevant in this case because all degrees in the article are in Celsius, and the Wikipedia article's primary scale is Celsius)
Both the sources you linked say that 35 degrees is the limit in the shade as well.
> It has been thought that a sustained wet-bulb temperature exceeding 35 °C (95 °F)—given the body's requirement to maintain a core temperature of about 37°C—is likely to be fatal even to fit and healthy people, unclothed in the shade next to a fan
Guess technically, since shade is cooler, then if the temperature was X and shade is (X-shade), then if wet bulb was at 95, then you could go into some shade to get cooler. Or, since wet bulb is at 95 is same in sun and shade, then if it is at 95 deg in shade you are in danger, and if you walked into the sun, you'd be in even more danger.
or to try and say another way. Temperature is Temperature, and if in Sun you are probably hotter. But wet bulb 'limit' would be same, and you'd hit the limit faster in the sun.
With the high humidity in the area, it was quite dangerous. An estimated 600 deaths due to the heat.
I'm sorry the people of the Philippines are going through this.
The heat there in the summer is no joke.
I wonder what actual temperature that gives them. I'd expect that whatever temperature they set below 25C would have the AC go full power either way, and never reach that target until at night perhaps.
Started plugging in some numbers into a heat index calculator just for kicks (https://www.omnicalculator.com/physics/heat-index).
I live in a very hot and dry area, and noticed that at 15% humidity the heat index matches temperature, below 15% results in a heat index below the temperature, and above 15% gives a heat index above the temperature.
> Temperatures measured directly on the ground may exceed air temperatures by 30 to 50 °C (54 to 90 °F).[6] The highest natural ground surface temperature ever recorded may have been an alleged reading of 93.9 °C (201.0 °F) at Furnace Creek, California, United States, on 15 July 1972.[7] In 2011, a ground temperature of 84 °C (183.2 °F) was recorded in Port Sudan, Sudan. [1]
[1] https://en.wikipedia.org/wiki/List_of_weather_records#Measur...
Filling the void and dead air time, commentators resorted to demos like "frying an egg on center court" to show just how hot it was.
Because the effect of the sun induces massive, extremely localized variations in apparent temperature. Are you wearing a black shirt or a white shirt? That changes apparent sun temperature. What is the color of the ground you're standing on? What is the material, for that matter?
Note that all of these effects will only increase the temperature (during daytime, at least). The shade temperature is thus a good indicator of what the coolest possible outdoor environment will be.
At "wet bulb temperature" your sweat doesn't cool you down anymore.
Said chapter is available from the publishers here: https://www.orbitbooks.net/orbit-excerpts/the-ministry-for-t...
A bit like citing Paul Ehlrich's hypothetical predictions of massive famines in the world of his future.. Oh but wait, they all turned out to be completely false.
Global albedo modification happens today its just not very directed (eg. pitch black tarmac next to concrete sidewalk there is significant difference in temperature on sunny days, AC bills would be probably bit cheaper we didn't have tarmac).
We're most likely utterly fucked whatever we do unless we go back to live like pre industrial revolution humans
My naive understanding would be that if the temperature > human body temperature, we can only gain heat from the environment, leading to death. Obviously sweating is involved. But how?
Basically, when we talk about a substance's temperature, that temperature is the average temperature of the system.
Temperature is just "how quickly are the atoms/molecules here jiggling?" When the atoms/molecules collide, some of them speed up, some slow down. That means that some atoms are "hotter" than the average temperature, and some are cooler.
Liquids have a certain energy above which a molecule is ejected from the puddle. This is evaporation.
Even if the average temperature (read: energy) is below that threshold energy, some molecules are moving faster, because they have collided with other molecules in just the right way. Those fast molecules get ejected. Evaporation!
But now that the puddle lost the fast (read: hot, read: high energy) molecules, the average energy of the system is lower. The whole thing cools down!
In dry environments, it's possible for sweat to evaporte (cool) at a rate that is faster than the rate at which your body heats up from hot colliding air.
In humid environments two things happen: evaporation slows down, and you heat up faster.
So there is a combination of temperature & humidity at which, if either of those parameters is exceeded, you gain heat faster than you lose it.
Heat flux is proportional to temperature difference, and is solely in the direction of hot to cold.
Let us suppose that at 27 C, the natural heat generation is shed, and let us also suppose that the core body temperature is 37 C. (The actual values don't matter, but this feels approximately correct and gives nice round numbers). In this case, if the temperature is below 27 C, then we are losing too much heat and our body temperature will decrease. If it is above 27 C but below 37 C, we're not shedding our body heat fast enough, so body temperature will increase. If it is above 37 C, then the environment is actually adding excess heat into our body instead of cooling it--and we still have natural metabolic heat to shed.
So we have three main mechanisms we use to regulate body temperature.
The first mechanism is to change the heat flux: by changing our clothing, we can control heat loss. This is obviously more effective for cold temperatures than warm temperatures.
The second mechanism is to change our internal heat generation. For example, staying more active in cold conditions or being less active in hot conditions. The response of shivering is in fact an attempt to generate extra heat to mitigate heat loss.
The final mechanism is to use evaporative cooling. Converting liquid water to gas requires energy. So if you coat yourself in water that gets evaporated, it actively sucks heat away from you in the process. The wet-bulb temperature is a measurement of the coolest you can make something in this method... and that's why wet-bulb temperatures near body temperature are lethal: it's the point at which you just cannot shed any heat whatsoever.
4) Increase/decrease the blood flow towards our skin and arms/legs.
This is why in hot conditions, blood vessels may widen, the heart pumps harder to increase core <-> skin heat exchange, and you see people blushing.
In turn, this "heart pumps harder" (or failing to do so) may worsen other conditions (especially in older people), and eg. contribute to kidney failure (and that in turn, to blood poisoning).
Without sweating, we’d be dead even if the air temp was near body temp because of the delta in temperatures required to transfer excess heat from our bodies.