Heat and Humidity Are a Killer Combination

In the future, the mix of heat and humidity could be so extreme that the evaporation of human sweat may not sufficiently cool our bodies.

Comments: 48

  1. I wonder how much thought has been given to things like transportation. I'm a pilot, and piston airplanes would have a tough time in such weather, as would anything with a turbine engine in it.

  2. We have had such terrible humidity in New York that the front door to my apt. barely functions anymore. It's not unusual for it to "stick" in high humidity, but it is unusual for it to last this long and for me to have to not close it all the way after I go in because I may not be able to open it again to go out. This happened the other morning. I had let it slam behind me the night before, and when I got up early in the morning to open the door from the inside to get the paper (NYT no less) I could not get the door open. I thought I was going to have to call someone from the building to come kick it in from the outside (which is what I often have to do when I go home at night) but I finally got it open.

  3. Thank you, NYT, for continuing to print stories about the catastrophe we are all facing. Maybe, just maybe, the significance of it will sink in to those in power and those who can do something serious about it.

    I cannot wrap my head around how people such as the Kochs and others who make money from fossil fuels cannot see how this affects everyone, including them and theirs.

  4. They think that their wealth will protect them and maybe a space ship to Mars.
    The thing is the Kock Bros. and their ilk are insane with money and thus very dangerous.

  5. It was a weird summer in central Oklahoma this year. Usually we hit at 100 degrees, sometimes as often as 30 days. This summer was much cooler, rarely getting above 90. Here's the weird thing. It was so humid as to be miserable. Clothes were just soaked in sweat. Eighty-five degrees in this humidity felt more uncomfortable than 100 when it was dry. Sweat just did not evaporate. It felt like working in a steam bath.

  6. It has been similar in New York City since July. We had more days than normal of 90 plus temps, but we had some breaks in that. But what we have not had much of a break in is the humidity, which continues to this day. Usually, at least by the middle or end of September we've had a couple of nice sunny days where both the temps AND humiidity drop, but that has not been the case theis year.

    I wish the weatherpeople would get less excited about consecutive days of 90 plus temps and more excited about consecutive days of 70 plus dewpoint.

  7. The issue of the dangerous heat and humidity combination is well presented, i.e. scientifically without exaggeration about dangers or underplaying them.

    Together with the consequences of the IPCC’s Fifth Assessment Report humanity has to make really drastic systemic personal lifetime changes. One pathway for doing this is transforming the unjust, unsustainable, therefore, unstable international monetary system by adopting a carbon standard of a specific tonnage of CO2 per person. The conceptual, institutional, ethical and strategic dimensions of such system with its carbon reduction system of a Hansen/McKibben model of fee and dividend are presented in Verhagen 2012 "The Tierra Solution: Resolving the climate crisis through monetary transformation" and updated at www.timun.net.

    Outstanding economist and climate advocate Bill McKibben stated about this Tierra Fee and Dividend system: “The further into the global warming area we go, the more physics and politics narrows our possible paths of action. Here’s a very cogent and well-argued account of one of the remaining possibilities.”

  8. Another climate change article silent about the impact of population growth on global warming.

  9. @Justin,

    Climate change will solve the population issue on its own. The key will be to not allow millions to travel from their ruined countries to countries that still have a chance.

    The US, if it is to protect its own people, must create clear policies barring any and all people from emigrating to the US.

    Each country will be on its own. I wish the world good-luck.

  10. WillT26 - Low-emissions countries become high-emissions countries as they are afforded the comforts of electricity and the availability of A-C.

  11. WillT26--Climate change will, no doubt, solve the population 'issue.' But that won't stop climate change.

    Additional warming is already baked into the system--oceans will continue to warm, ice will continue to melt, and CO2 in the atmosphere will continue to retain solar heat.

    In fact, given that the richest countries are the biggest carbon emitters, atmospheric CO2 will continue to rise.

    You should also understand that, given our role in emitting CO2, your statement would likely be perceived in much of the world as asserting a right to kill them off without suffering consequences ourselves.

    Even if you believe in America First, that's a rather extreme position.

    I tend to believe that the wealthy and extremely wealthy are likely to save themselves and leave the rest of us, regardless of nationality, to suffer and die. But maybe I'm just paranoid.

  12. Good article, and ties in with other studies that point out that these conditions will lead to economic damages due to lost productivity in areas affected. Moving work to nighttime might mitigate a little bit, but a big factor in the deaths here in Chicago was that nights didn't cool enough for the victims, mostly elderly, to recover from the stress of daytime peaks. We were far below the simply-lethal level, but at lower levels, recovery time is necessary - either AC or cool nights, in heatwaves.

    So Chicago now has cooling centers and does wellness checks to deal with it happening again, but working to prevent the cause of the event has to be the biggest part of the solution, because it doesn't just affect humans. It affects large mammals.

    "On July 31, 2015 in Bandar Mahshahr, Iran, the heat index reached 165 degrees, among the highest ever recorded. [...] residents were able to take refuge in air-conditioned buildings, middle-class luxuries that don't exist for many in the hottest regions."

    These luxuries also don't exist for livestock and wild mammals. During prior times when greenhouse concentrations led to much higher temperatures, large animals did OK - dinosaurs, crocodilians, reptiles. Large mammals couldn't survive those conditions then, and won't in the future.

    So we face a risk of seeing all large mammals, even healthy ones, die in areas affected by just a day or two of extreme conditions that business as usual will drive towards possibility.

  13. B Fagan - Born in Joliet, 8 - 17 grew up in Moline Il.

    I remember summer days so hot and humid in the early 70's in Moline, that when you went outdoors, the heat-humidity combo would just slam you. My recollection was that the temp was like 85 and the humidity was like 75. And that was soooo hot.

    There are areas of the USA which are much nicer in the summer. I currently live in a state west of the great divide. This summer was hot for a long time, but the humidity is usually under 15%. So if the temp gets up to 95 you can still walk around, maybe ducking into tree shade (or a cool bar) every chance you can, but you can still be out and about.

  14. It is curious that this is published in the Opinion section. It is based on best projections of climate change, which is more factually based than many opinion pieces. That being said, the projections are very concerning, and emphasize the need for real action. This means pressure from the people on our leaders, as despite 30 years of concern, give or take, little has been done so far. We do, most likely, have the technology and ability to make the necessary changes, but it will take effort and work. ( I suspect if our budget for research, technological improvement, and infrastructure improvement was 1/3 the money spent on the military over the last 20 years, we would be MUCH farther along at this point.)

  15. That was the first thing that went through my mind. No wonder scientists have such difficulty in getting climate change taken seriously.

  16. At some point, when the very parched barbarians are at every northern country gate, our military budget will have to cover the consequences of global warming. Why not start now?

  17. I have suffered from heat exhaustion, from a strenuous bike ride on a hot day but no where near as hot as those the article forecasts. It's a dangerous condition and doesn't go away on it's own. Hydration is not sufficient--in fact it can be counterproductive. Quite often, hyponatremia, the depletion of electrolytes, is more critical.

    Don't be fooled by sports drinks that promise to restore electrolytes; it really can't be done on the fly. The best course is to get to a cool place where a doc can stick an IV into your arm. Failing that, chicken soup and rest can't hurt.

    Heat exhaustion is just the first stage. Heat stroke is far more dangerous.

    But on some level, I must wonder whether efforts to preserve life are just delaying the inevitable. Those that suffer from heat exhaustion this year must realize that heat indices aren't going to get any better next year.

  18. "Questions about how wildlife and natural ecosystems will be affected by humid heat are also mostly unexplored."
    Great job, sticking this sentence in at the very end of the article. Couldn't one of you have spent 15 minutes to explore it?

  19. Well I read that to mean that scientists and the general society at large, which is exploring/tackling these questions, have yet to appreciably do this. Therefore there is not much verified research to even report on to the rest of the public, via this article. If there was then I think this article would have reported more than just that sentence regarding that.

  20. I don't know why you and other media don't use dew points. When the dew point is near the temperature, moisture does not evaporate from the skin with the resulting problems detailed in the article. When weather forecasts and reports show dew point maps and data, viewers can easily understand and predict how uncomfortable they will be.
    When the temperature is 90F and the dew point is in the 50s, you can cool off in the shade, but if the dew point is 80, which occurs regularly in the tropics, you are into the danger zone where even the shade provides no cooling.
    Relative humidity changes throughout the day as the temperature changes. Dew points incorporate air pressure and remain constant even when the temp changes through the day.
    Weather forecasts in some areas and on some weather websites list the dew point. You can predict just how uncomfortable you will be no matter what the temperature is.

  21. AKA "wet bulb" temperature. - At 100% relative humidity, the wet-bulb temperature is equal to the air temperature and is lower at lower humidity. It is defined as the temperature of a parcel of air cooled to saturation by the evaporation of water into it, with the latent heat supplied by the parcel. Wikipedia


  22. I agree. The current dewpoint is reported on some weather websites. But it is practically impossible to get historic data to show trends, or to tind an estimate of it in 10-day forecasts. I raised this with a local "weathercaster" when he tweeted the statistics on this summer's heat in New York (20 days at 20F plus). I asked how many days at dewpoint 70 or above, which is the point where it is considered "oppressive." He said they didn't keep records of dewpoints -- that I would have to go to National Weather Service and look at individual daily records.

    I think New YOrk City since about July has been terrible -- though we've had a few breaks in tems, practically no breaks in humidity. We had a whole week in July where the temps dropped to high 70s (and described as "beautiful" by some "weathercasters," but the humidity was close to 90 that whole period).

  23. Sorry, in my earlier post that should have been "(20 days at 90F plus)."

  24. This is why the entire population of the central band of the earth is trying to get to the northern band (which has more land than the Southern Hemisphere). Migration northward will only get worse.

  25. I had heat exhaustion last summer just once. I live in London, where heat is not as extreme as in a lot of parts and cities in the USA, but I do take medication for heart conditions, diabetes, high blood pressure and also some neuroleptics. Half of my medication bottles warn "avoid hot and humid places."

    I carry now a bottle. An ordinary plastic bottle. When I get hot, I use the simple Hungarian A/C method: I fill the bottle with cold water, and pour it on top of my head, letting it flow to all directions onto my body below. Works wonders.

    I believe I will see the day when I wake up one morning and see myself get so immensely hot, from one moment to the next, that I will cry in pain, then get parched on the outside, and finally burst into a fluff of smoke like a moth that flies into a flame.

    I say it will be that rapid, because I firmly believe -- and this is a belief, without supporting evidence, so it's like a religion -- that the Earth's warming is due to astrophysical changes, not due or entirely due to some guilty habit by humanity such as burning fossil fuels.

  26. Wearing a sombrero or straw hat isn't just to protect from UV on the face, it also keeps the brain cooler. Overheated brains where there is ample blood vessels leads to strokes.

  27. Another downside or danger is the large uptick of skin cancers. It is growing quickly all over the world. If you have not already, get a screening by a doctor.
    I demanded one and ended up with having several spots that tested positive and then had them surgically removed. If you wait too long, it can be fatal.

  28. Skin cancer is linked to high humidity? Where is that reported?

  29. Skin cancer has nothing to do with temperature. If you go indoors or cover up to get away from the hot sun, you are less likely to get skin cancer.

  30. We have lived with this reality for decades. Nobody goes outside without sunscreen here, and everyone knows at least one person who has had one cancer removed, or has died from melanoma. It's an entire medical industry here. That's just about awareness. Once you get the hang of it you will check moles regularly, and go through the 'slip, slop, slap' routine (slip on a shirt, slop on sunscreen, slap on a hat) - that's what we teach kids here.

  31. Heat and Humidity Are a Killer Combination

    Not if you grow corn. It will grow more than an inch - a day

  32. "Not if you ARE a corn"

    there, fixed it for you. no one is going to be able to "grow" corn when it is growing at that rate due to extreme weather.

  33. JA - And you do not know corn, or sunflowers for that matter.

    Knee-high by the fourth of July.

    That same corn is ready for harvest 60 days later and is 7 ft tall.

  34. I agree with others: why is this in the opinion section? This is not an opinion, this is a report on our best projections of climate change. This is also an under-appreciated impact of global warming that deserves more coverage. The very fact that whole swaths of the Tropics could become barely livable because of near-lethal or outright-lethal heat waves is kind of ...I don't know, mind-boggling.

    One thing that is missing in this report, though. is under what socio-economic scenario these projections are made. I suspect these are for a business-as-usual scenario (which hopefully we can avoid, at least in part). If that's the case, then one thing to keep in mind is that warming (and "humidifying") under that scenario doesn't magically stop in 2080 or 2100: it actually continues, slowly, all the way to 2200 or 2300...

  35. It is ironic - the areas with the higher average temperatures are also areas with the greatest population growth.

  36. i guess i serve as a canary in the coal mine. i have residual R hemiparesis and attendant severe nerve damage, both of which caused my biofeedback doctor 30 years ago to declare me a 'human barometer'.

    fast forward to this past summer, and even today with mild temps and impending rain, wherein i lost approximately 4 months to my body over-ruling my mind. yes, i forewent a/c for the enviroment, ridiculous costs, and maintenance.

  37. As the middle class rapidly expands by millions in countries like China and India, the first thing they want or need is air conditioning and a car. This will most certainly seal the deal or tipping point of no return.
    Along with the northern tundra thawing and releasing massive amounts of methane gas. Things are not looking too good for our spaceship earth.

  38. We all complain, analyst, think and look at those science sophisticated datas, but remember every time you consume things or do these things in this americanize society, you already contribute to make our climate change to the worse • Eat take out or call for food delivery (things like this don't really exist in many part of the world, hard to find food delivery in major European cities or Asia, except pizza) • Recently IKEA cafeteria in Brooklyn doesn't use real plates, cups and silver utensils anymore, when the concept of the affordable cafeteria comes with being sustainable in both food and how you serve it, the cafeteria design also has place to put dirty dishes. Lazy staff and customers. • Parties both for kids and adults using loads of plastic utensils, paper plates (what's wrong with your dishwashers). • Those online services with loads of shipping in boxes back and fourth (online clothing rental subscription), Preset meals delivery just because you want to cook and can't bring recipes to shop at supermarket anymore. To be fair, this kind of wanna be chef services are more in the metro areas, not in the remote country side. • Shopping in supermarkets using loads of plastic bags instead of bringing your own reuse bags. • Anti-bike lanes people in NY who obviously wouldn't want to bike or take publics. They exist, with lame excuses just because they want to drive and bike lanes take parking spots away! And you wonder why climate change get worse, without doing a thing..

  39. More non stop good news, from The New York Times! Obviously, we are all doomed probably earlier than we think!!!

  40. "None like it hot."

  41. Thanks Republicans.

  42. Virtually everyone in Phoenix has air conditioning. And when outside, virtually everyone carries water. But there is one huge problem. There are a good number of folks who can't afford to run their air conditioners during the summer. And while there is a subsidy program, it is ridiculously underfunded -- only 3.5% receive benefits.

    Air conditioning in Phoenix is like heating up north. If it isn't available, you've got a life threatening crisis.

  43. Read the fine print. These are predictions making certain (pessimistic) assumptions about greenhouse gas emissions and climate sensitivity. Not only are temperature predictions uncertain, but almost no attention has been paid to the validity of humidity predictions that are essential but likely equally uncertain. Also note that "heat index" does not directly map onto wet bulb temperature (the actual physical variable). And "weather station data...do not match model-estimated historical heat indices"; in other words, where the models have been tested, they have got it wrong.

    Societies in hot climates adapt by deferring outside work to the morning and evening (the siesta of Spanish and Mediterranean cultures), by building structures of adobe that average the daily temperature cycle, being warm at night and cool in the hottest part of the day...

    Don't panic.

  44. @Jonathan - Don't panic is good advice. We should instead work calmly, rapidly and with determination to reduce greenhouse emissions as fast as we can, and panic reduces accuracy when accuracy is needed.

    What strikes me as kind of sad is how people who look at an article about climate, and then go "Oh ho! Their model didn't match 100%!!!" always seem to then make a default assumption that is completely unsupported by statistical uncertainty - namely, that the outcomes will automatically be LESS dire than things indicate. Outcomes could be worse than projected, too.

    Here's a list of changes that are already underway and that will progress based on how much effort we put in to stopping what we know are harmful behaviors:

    - spread of hot climates (adobe in St. Louis, and siestas!)
    - ocean chemistry trending in the direction bad for calcium-shelled creatures
    - warming oceans and less dissolved oxygen
    - changing precipitation patterns trending towards heavier precipitation in fewer events, and trends towards longer droughts
    - changing temperature patterns, higher for most places
    - measured rising sea levels from measured warming of oceans
    - measured rising sea levels from measured melting of land-based ice
    - measured spread of insect pests into formerly cold areas

    But because projecting the future, even based on the most current understanding of dozens of scientific disciplines is still, in fact, predicting the future, some want to bet everything will roll our way.

  45. I saw, but did not read, this article this morning on my digital homepage. In the afternoon, I had to use the NYT search to find the article. Why? This is an article of interest to us all.

  46. The issue of the dangerous heat and humidity combination is well presented, i.e. scientifically without exaggeration about dangers or underplaying them. Together with the consequences of the IPCC’s Fifth Assessment Report humanity has to make really drastic systemic personal lifetime changes. One pathway for doing this is transforming the unjust, unsustainable, therefore, unstable international monetary system by adopting a carbon standard of a specific tonnage of CO2 per person. The conceptual, institutional, ethical and strategic dimensions of such system with its carbon reduction system of a Hansen/McKibben model of fee and dividend are presented in Verhagen 2012 "The Tierra Solution: Resolving the climate crisis through monetary transformation" and updated at www.timun.net. Outstanding economist and climate advocate Bill McKibben stated about this Tierra Fee and Dividend system: “The further into the global warming area we go, the more physics and politics narrows our possible paths of action. Here’s a very cogent and well-argued account of one of the remaining possibilities.”

  47. Strange how most of the darker colored regions on the map, those most likely to be impacted by the combination of heat and humidity, generally centered around the equator, are also those with the highest birth rates. The NYT is for some reason loathe to mention overpopulation in almost all of these articles centered around climate change. 8 billion is too many people for the 3rd rock from the sun, and it's projected to be around 11 billion by mid-century. The numbers might be curtailed by dwindling resources, dying oceans, and wars over water and food supplies. In any event, those most severely impacted will be the elderly, those with pre-existing medical conditions, and the youngest. That's how it works with Mother Nature in the animal kingdom. Those are the ones that struggle when food is scarce- the young and elderly and physically compromised can't hunt their prey or outrun their predators. We're just animals that walk upright with supposedly bigger brains. Those bigger brains aren't necessarily better though, humans are the cause of the coming calamities. Pogo was right. So was that native American chief who said one day when all the food is gone along with the clean water and clean air, the rich will finally discover that you can't eat, drink, or breathe your money. You can't even take it with you.

  48. @drdeanster - it's a problem, but we have to face the fact that population growth from births didn't stop growing in the temperate wealthy countries until living standards increased to the point where parents had confidence that they'd have someone to survive to care for them in their old age. Fast forward and it's showing in nation after nation that population growth flattens when a - health and security improve b - women have access to education and to birth control In short, populations in developing nations have to develop their way out of population increase. They'll be doing so in increasingly urban concentrations, and it's in all of our interest to help make sure they can build those cities and stabilize their populations using energy efficiency and clean electrification as much as possible. China and India don't -want- to have millions die from pollution as they raise standards of living, but coal was the quick way when they started, and their people died like Americans and Europeans in the 50s and 60s. But as the problem becomes more acute, the solutions are maturing too. Just like many countries skipped the immense landline infrastructure for telephones, nations growing out of their birthrates now have a lot more and better energy architecture options than the clunky grid-and-massive-power-plant structure we developed with.