Johnny Carson of the Tonight Show used to do a schtick called “The Edge of Wetness” which was a parody of a soap opera called “The Edge of Night”
It was he first thing that went through my mind after reading this press release citing a new worry about wet bulb temperature. Apparently it’s not just the heat, but the humidity too.
Researchers find future temperatures could exceed livable limits
This map shows the maximum wet-bulb temperatures reached in a climate model from a high carbon dioxide emissions future climate scenario with a global-mean temperature 12 degrees Celsius (21 degrees Fahrenheit) warmer than 2007. The white land areas exceed the wet-bulb limit at which researchers calculated humans would experience a potentially lethal level of heat stress. (Purdue University graphic/Matthew Huber)
WEST LAFAYETTE, Ind. – Reasonable worst-case scenarios for global warming could lead to deadly temperatures for humans in coming centuries, according to research findings from Purdue University and the University of New South Wales, Australia.
Researchers for the first time have calculated the highest tolerable “wet-bulb” temperature and found that this temperature could be exceeded for the first time in human history in future climate scenarios if greenhouse gas emissions continue at their current rate.
Wet-bulb temperature is equivalent to what is felt when wet skin is exposed to moving air. It includes temperature and atmospheric humidity and is measured by covering a standard thermometer bulb with a wetted cloth and fully ventilating it.
The researchers calculated that humans and most mammals, which have internal body temperatures near 98.6 degrees Fahrenheit, will experience a potentially lethal level of heat stress at wet-bulb temperature above 95 degrees sustained for six hours or more, said Matthew Huber, the Purdue professor of earth and atmospheric sciences who co-authored the paper that will be published in Thursday’s (May 6) issue of the Proceedings of the National Academy of Sciences.
“Although areas of the world regularly see temperatures above 100 degrees, really high wet-bulb temperatures are rare,” Huber said. “This is because the hottest areas normally have low humidity, like the ‘dry heat’ referred to in Arizona. When it is dry, we are able to cool our bodies through perspiration and can remain fairly comfortable. The highest wet-bulb temperatures ever recorded were in places like Saudi Arabia near the coast where winds occasionally bring extremely hot, humid ocean air over hot land leading to unbearably stifling conditions, which fortunately are short-lived today.”
The study did not provide new evaluations of the likelihood of future climate scenarios, but explored the impacts of warming. The challenges presented by the future climate scenarios are daunting in their scale and severity, he said.
“Whole countries would intermittently be subject to severe heat stress requiring large-scale adaptation efforts,” Huber said. “One can imagine that such efforts, for example the wider adoption of air conditioning, would cause the power requirements to soar, and the affordability of such approaches is in question for much of the Third World that would bear the brunt of these impacts. In addition, the livestock on which we rely would still be exposed, and it would make any form of outside work hazardous.”
While the Intergovernmental Panel on Climate Change central estimates of business-as-usual warming by 2100 are seven degrees Fahrenheit, eventual warming of 25 degrees is feasible, he said.
“We found that a warming of 12 degrees Fahrenheit would cause some areas of the world to surpass the wet-bulb temperature limit, and a 21-degree warming would put half of the world’s population in an uninhabitable environment,” Huber said. “When it comes to evaluating the risk of carbon emissions, such worst-case scenarios need to be taken into account. It’s the difference between a game of roulette and playing Russian roulette with a pistol. Sometimes the stakes are too high, even if there is only a small chance of losing.”
Steven Sherwood, the professor at the Climate Change Research Centre at the University of New South Wales, Australia, who is the paper’s lead author, said prolonged wet-bulb temperatures above 95 degrees would be intolerable after a matter of hours.
“The wet-bulb limit is basically the point at which one would overheat even if they were naked in the shade, soaking wet and standing in front of a large fan,” Sherwood said. “Although we are very unlikely to reach such temperatures this century, they could happen in the next.”
Humans at rest generate about 100 watts of energy from metabolic activity. Wet-bulb temperature estimates provide upper limits on the ability of people to cool themselves by sweating and otherwise dissipating this heat, he said. In order for the heat dissipation process to work, the surrounding air must be cooler than the skin, which must be cooler than the core body temperature. The cooler skin is then able to absorb excess heat from the core and release it into the environment. If the wet-bulb temperature is warmer than the temperature of the skin, metabolic heat cannot be released and potentially dangerous overheating can ensue depending on the magnitude and duration of the heat stress.
The National Science Foundation-funded research investigated the long-term implications of sustained greenhouse gas emissions on climate extremes. The team used climate models to compare the peak wet-bulb temperatures to the global temperatures for various climate simulations and found that the peak wet-bulb temperature rises approximately 1 degree Centigrade for every degree Centigrade increase in tropical mean temperature.
Huber did the climate modeling on supercomputers operated by Information Technology at Purdue (ITaP), Purdue’s central information technology organization. Sherwood performed the wet-bulb calculations.
“These temperatures haven’t been seen during the existence of hominids, but they did occur about 50 million years ago, and it is a legitimate possibility that the Earth could see such temperatures again,” Huber said. “If we consider these worst-case scenarios early enough, perhaps we can do something to address the risk through mitigation or new technological advancements that will allow us to adapt.”
Writers: Elizabeth K. Gardner, 765-494-2081, ekgardner@purdue.edu
Greg Kline, 765-494-8167, gkline@purdue.edu
Sources: Matthew Huber, 765-494-9531, huberm@purdue.edu
Steven Sherwood, +61 (2) 9385 8960, s.sherwood@unsw.edu.au
Related Web site:
Matthew Huber’s Climate Dynamics Prediction Laboratory
ABSTRACT
An Adaptability Limit to Climate Change Due to Heat Stress
Steven C. Sherwood, Matthew Huber
Despite the uncertainty in future climate change impacts, it is often assumed that humans would be able to adapt to any possible warming. Here we argue that heat stress imposes a robust upper limit to such adaptation. Peak heat stress, quantified by the wet-bulb temperature Tw, is surprisingly similar across diverse climates today. Tw never exceeds 31C. Any exceedence of 35C for extended periods should induce hyperthermia in humans and other mammals, as dissipation of metabolic heat becomes impossible. While this never happens now, it would begin to occur with global-mean warming of about 7C, calling the habitability of some regions into question. With 11-12C warming, such regions would spread to encompass the majority of the human population as currently distributed. Eventual warmings of 12C are possible from fossil fuel burning. One implication is that recent estimates of the costs of unmitigated climate change are too low unless the range of possible warming can somehow be narrowed. Heat stress also may help explain trends in the mammalian fossil record.
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Journalistic “Peer Review” strikes again! And again, and again, and again….
Several web sites say that the highest dew point on record was at Dhahran, Saudi Arabia on 2003 July 8. The local airport data is available at http://www.wunderground.com/history/airport/OEDR/2003/7/8/DailyHistory.html?req_city=NA&req_state=NA&req_statename=NA and at 1:00 PM lists 107.6 °F air temp, 95.0 °F dew point, 68% RH.
That corresponds to a wet bulb temperature of 97.2°F, 36.2°C, so there is still some cooling potential there. Not much, though. The paper says “The researchers calculated that humans and most mammals, which have internal body temperatures near 98.6 degrees Fahrenheit, will experience a potentially lethal level of heat stress at wet-bulb temperature above 95 degrees sustained for six hours or more.
An hour later, the air temp climbed to 109.4, the dp declined to 91.4, the wet bulb declined to 94.8.
It was also sunny, all that’s required for high humidity to not make clouds is to have hot temperatures aloft so convection can’t develop.
So, setting the fantasy of future temperature gains aside, say few people here have experienced the potentially lethal conditions described above.
And now your latest news from the Wet-Bulb Capitol of the US. (Other wise known as Tampa Bay, Florida)
143 landscapers died yesterday (a new record) from the Wet-Bulb temperature anomaly of + .04C that we experienced throughout the Bay area….. (well, they mat not have actually “died”, that’s what the computer model said happened, and of course, if the Computer Model God, says so, AND that fits the Emperor’s agenda, we are obligated to report it). And pay no attention to that person behind the curtain…. and just wait until August, when it’s REALLY hot! The computer is predicting 1,000!
It’s currently 80°F in Charleston SC. I need to go put on some long pants and a shirt – a bit too chilly for me, even with my gluttonous 3 computers pumping out wasted heat.
I have 3 thermometers, the Windows 7 widget and 2 web sites telling me the temperature. Strangely enough, I always have to actually *go outside* to see what the temperature really is.
It is becoming apparent that these Models are simply the modern day version of the psychics Crystal Ball.
Correct me if I’m wrong here but havn’t they just worked out a temperature that they THINK MIGHT kill you and then simply stated that thats what they THINK MIGHT happen?
In the next century, all the people over 50 years old today, will be at least 150 years old. This is a catastrophe in the making. No planning or infrastructure is in place to take care of these old people. It will be unprecedented – this has never happened before but could happen at the current rate of aging…
Didn’t I see this in a classic Twilight Zone episode? I guess these guys got their “degrees” from the University of Hollywood!
Hey, if I could survive summer in Tulsa, OK, I can survive this! What nonsense….
Dave Wendt says:
May 5, 2010 at 2:25 am
Show me one, either in Minnesota or Brownsville, TX. 100F at 88% RH corresponds with a dew point of about 96F.
http://www.shorstmeyer.com/wxfaqs/humidity/humidity.html says about Cincinnati OH, “One last thing if you ever hear someone say it was 90°F and the humidity was 90%, that has never happened in Cincinnati, (and unless the greenhouse effect goes into overdrive never will). 90°F/90% requires a dew point of 85.5°F. In Cincinnati the highest ever dew point was 81°F. for just a few minutes.”
In August 1995 we had four hours of 78°F,79°F,78°F,77°F dew points, the highest persistent dew points I have seen in Cincinnati since working here as a meteorologist. For one hour I did see a dew point of 81°F, just after a thunderstorm.”
Every time I read a study and think it just can’t, it just CAN’T, get any more ridiculous… I find out that I am not very good at predicting the future. I can’t even summon a sarcastic remark. The effects might start to show up with a 7 degree C rise? Full blown at 12? Based on a computer model that exceeds the wildest predictions of even the IPCC? Can I ask, why did they stop at 12? What it it turns out that we can survive +12 or +15 even, what happens at +85? Will the oceans start to boil? Is that not a larger concern than just surviving high wet bulb? We can build giant indoor cities with climate control, but what about the oceans boiling? is that not the greater threat? Would that not disrupt shipping? Would the sea creatures all die or would they evolve to survive the heat? and if they evolved, would they still need to be cooked before eating? Would sauna manufacturers all go out of business and would the government have to subsidize them because they are too big to fail? What about money? Paper money would turn to much wouldn’t it? OK, maybe the sarcasm gene didn’t get totaly suppresed, just wilted for a bit.
Just in case the warming is natural and CO2 abatement won’t help, perhaps we should look at a water sequestration system? It we bottle it ALL we can then control how much gets released into the atmosphere.
I’M WET! I’m wet and I’m in pain and I’m still hysterical!
[The Producers]
Okay, let me see if I’ve got this straight…
In order for this scenario to play out, it must meet the following criteria :
– consistant neverending overall complete global temperature rise of up to 25C (that means pole to pole, all year round, night and day, nonstop)… basically, the same temperatures around the globe at the same time, consistantly.
– no more seasons… being closer or farther from the sun no longer matters, nor does the tilt of the earth matter either… temperatures will be globally consistant and continueously rising, all the time.
– ongoing increasing atmospheric saturation levels (that means no limit to saturation levels globally, which means no cloud formation, rain, snow, clumping droplets, etc etc).
– the hydrologic cycle (especially ocean circulation) must come to a complete halt and be consistantly so (forever and ever, amen).
– global climate must revert back to cambrian conditions when CO2 levels were at 4000 ppm, the globe was covered in vegetation, the oceans had higher algae count, and the sun was 30% hotter… even though the global temperatures weren’t 25C higher back then, we should still count this in anyway and add to our ‘what if’ scenario just to be on the safe side.
– all glaciers, ice caps, ice floes, etc etc must all be completely melted and permanently gone… which of course would mean that sea levels globally would be 20 metres higher… everywhere… which of course would mean more water surface coverage and less land coverage globally… (but the hydrologic cycle is at a halt anyway, so ignore the water coverage thing).
– consistant runaway net positive feedback… no matter what, come hell or high water (pun intended).
Hmm… have I missed anything else ?
Alrighty then. I’ve taken into account all criteria mentioned above and have come to the conclusion that, YES, this scenario is very highly feasible…
…In an actual enclosed glass greenhouse, that is !
Okay… NOW I understand why they call it the greenhouse effect. And just think, all this time we thought our planet was an open atmosphere… but in reality our planet is actually completely surrounded and enclosed in a glass casing ! Why haven’t the scientists told us this ?!
… which leads me to other questions :
How did the astronauts get to the moon ?
Is there a glass door somewhere out there that they have to punch in their PIN number in order to open it up to continue with their journey ?
How does the rocket come to a stop so that they can pull up alongside the control panel to punch in their code ?
Is the glass door maintained and operated from earth or is it a natural cosmic thing on piano hinges ?
And how come the glass casing doesn’t shatter whenever a meteor plows through the sky and hits the earth ? Or is there sky-glass greenhouse repairmen that we’ve never heard of ?
What does the fact that this paper is being published by the NAS indicate about the NAS? It is an embarrassment.
Research requires money. Researchers require more money.
How much money was spent and from what source gave us this drivel?
Reform in climate science requiring publishing or providing data, both massaged and more importantly raw, is a must.
It would also be interesting if all science research products included reference to the amount and source(s) of funding for that research.
Many years ago I heard that this educational debacle had begun during the II WW when a kind of ‘”fast-food” professionals were needed to be produced and delivered ASAP, then synoptic tests were invented, where answers were provided beforehand so the students had just to check the correct answer.
So, this is “Fast Food Science”.
Northern Exposure, they use an adaption of the military’s IFF (Identification Friend or Foe) that has the password loaded in in the software. Today’s password is “Mann”
Smokey says:
May 5, 2010 at 10:20 am
“Here is another example of the insane direction the peer-review process has taken what used to be rational science. The authors of this study argue that China has the least environmental impact — while the U.S. is one of the worst environmental offenders.”
You misrepresent grossly now (cf. part of the abstract below).
The proportional index is what counts; you don’t find US or
China there (but Netherlands!). The absolute index just says
that large populated countries accumulate most impacts
(naturally) and Brazil, USA and China are on equal footing
(naturally). Where do you get your ‘China best – USA worst’
conclusion? Nowhere.
from the abstract
“Our rankings are based on natural forest loss, habitat conversion,
marine captures, fertilizer use, water pollution, carbon emissions
and species threat, although many other variables were excluded
due to a lack of country specific data. Of 228 countries considered,
179 (proportional) and 171 (absolute) had sufficient data for
correlations.
The proportional index ranked Singapore, Korea, Qatar, Kuwait,
Japan, Thailand, Bahrain, Malaysia, Philippines and Netherlands
as having the highest proportional environmental impact, whereas
Brazil, USA, China, Indonesia, Japan, Mexico, India, Russia, Australia
and Peru had the highest absolute impact (i.e., total resource use,
emissions and species threatened).”
davidmhoffer says:
May 5, 2010 at 11:08 am
It we bottle it ALL we can then control how much gets released into the atmosphere.
We are currently doing this to trillions of gallons a day. Also creating many products and storing them with the main ingredient; water.
I visited one of the authors’ websites… Mathew Huber’s Climate Dynamics Prediction Laboratory.
What Paleogene greenhouse?
CO2 levels during the Paleogene ranged from 200 ppmv to 900 ppmv. Though the eaarly Paleogene was very warm, there’s no indication that it was due to an enhanced greenhouse effect.
The Jurassic-Cretaceous might be aptly described as a “greenhouse,” with CO2 levels ranging from 900 ppmv to 2,500 ppmv.
Phanerozoic Temp and CO2
mikael pihlström,
For the first time I can recall, you are right. I conflated two of the tables in the paper.
However, see the 5th table down [Twenty Worst Ranked Countries]: The USA is ranked worse than China.
This reminds me of one of my professors, who put about two dozen unrelated nouns on the blackboard [I’m giving away my age here], and told the class to put them into two columns, using any criteria we wanted.
The result was that everyone easily came up with two columns of words they thought were related. But everyone had different words in their columns.
The professor explained this as an example of uncritical thinking. Human minds are made to recognize patterns, even when there really are none, as in numerology or phrenology.
That is the same thing that these perfumed, coddled and tenured educrats are doing here. By ranking the U.S. as having a lower environmental score than China, they are implicitly making China more virtuous environmentally. That is preposterous, as anyone who has traveled in both countries knows.
Finally, the quote regarding “species threatened,” which of course is intended to make the U.S. look bad, is an artifact. Polar bears are listed by the EPA as “threatened,” even though the population has exploded by 500% since the 1970’s. And where do the figures for countries like Gabon or Djibouti come from? The WWF? Greenpeace? PETA?
I suspect that anyone with access to the complete data and methodology could show that this ‘study’ is the equivalent of arbitrarily putting countries into columns with one hand, while putting the other hand out, palm up, toward the nearest government grant agency.
To Alan the Brit:
Sorry for the OT but:
If language didn’t evolve we’d still be saying:
Whan that Aprill, with his shoures soote
The droghte of March hath perced to the roote
And bathed every veyne in swich licour,
Of which vertu engendred is the flour;
Whan Zephirus eek with his sweete breeth
Inspired hath in every holt and heeth
The tendre croppes, and the yonge sonne
Hath in the Ram his halfe cours yronne,
And smale foweles maken melodye,
That slepen al the nyght with open eye-
(So priketh hem Nature in hir corages);
Chaucer 1342- Notice also he is talking about a drought.
If this scenario were to happen, mankind would be forced to respond with one of its earliest adaptations to climate, we’d head to the caves.
Dig down about 10 to 15 feet where it is in the 50’s (Fahrenheit) all year long, make a home. The spring or fall temperatures in the temperate zones, which just about anyone can survive in just fine. Except for local water table issues, this option is widely available to even the poorest of people who would be impacted. If there’s too much water to go down, go sideways until you find a hill. If you can’t find hills, then build a mound, humans have done it before. Use proper construction at the openings to prevent intrusion from precipitation events and you’re all set.
Another concurrent adaptation is shifting our schedules to nighttime when it’s cooler. We’ve evolved to normally having a daytime schedule with lousy night vision compared to practically any other critter. Well, as opposed to the original caveman days, we’ve developed great sources of artificial light so working at night isn’t that much of an issue. In much of the developed world we’re become a 24/7 society so we’re already nearly there.
You can already see such changes adopted in, amazingly enough, Las Vegas. There was an “alarming” TV piece not that long ago about the “tunnel people” who live in the runoff tunnels (storm drains) under the town. Some living spaces are actually set up rather comfortably, better than many third-world homes. Here’s a recent article with pics. Seemingly victims of the recent recession, the first page of Google results has articles going back to 2007. It’s a safe bet people have been setting up homes down there long before that, likely right after the construction was done.
Humans running back to their caves, leaving more of the surface to go back to nature; something the greenies will likely approve of.
Sioned L,
Isn’t that how doctors still write prescriptions?
Ric Werme says:
May 5, 2010 at 11:01 am
Dave Wendt says:
May 5, 2010 at 2:25 am
Here in southern Minnesota…
They claim wet bulb temperatures never exceed 31C. By my reconning that’s 100F @ur momisugly88% RH, hard to imagine that doesn’t get surpassed fairly regularly already.
Show me one, either in Minnesota or Brownsville, TX. 100F at 88% RH corresponds with a dew point of about 96F.
You got me. Admittedly it was 4 in the morning and I was running numbers in my head. According to the tables on this page
http://www.engineeringtoolbox.com/humidity-measurement-d_561.html
a wet bulb temp of 31C actually results in an RH value of 87% @ur momisugly 33C or 91.4F dry bulb temp. which unless the local weather guys have been lying to us all along is not that uncommon even here in Minnesota.
Even if I still have it all messed up, the presumption of a 12C rise in global temp still puts this in the category of “what were you guys smoking” and “did you bring enough to share?”
@ur momisugly Ric Werme says:
Dave Wendt says:
Heh, your little discussion peaked my curiosity. So, I engaged to find high dew points. During my course, I found this little gem. http://climate.umn.edu/doc/journal/dewpoint050723.htm . Essentially it discusses an abnormal event in Minnesota where dew point hit 86 degrees. But the real interesting part(considering the history of this web site.) was in the addendum. I quote “[Addendum: July 28, 2005]
In a follow-up investigation, the State Climatology Office discovered that the Pipestone and St. James dew point temperature sensors were reading three to four degrees higher than neighboring stations during June and July of 2005. Therefore, dew point temperatures in Pipestone and St. James reported on July 23 may have been erroneously high. However, both stations are well-maintained, government-sponsored observation sites whose data are widely distributed. Thereofore, the 86 degree dew point temperatures will remain part of the historical database.”
Sigh, who cares if it right or not, IT’S A RECORD!!! As I recall, and as is seemingly every other year, wasn’t 2005 one of the “hottest ever!!” What do you bet these two stations’ temps were part of that “record year”?