Guest Post by Kip Hansen
Science is a wonderful thing. As time moves on, in a single direction, Science, as an endeavor, discovers new things and improves our lives.
With a “hat tip” to the inestimable Jane Brody, health journalist at the NY Times who covers the story here, we are reminded of the study [free .pdf] from Antonio Gasparrini et al. which was published in The Lancet, July 25, 2015, with the [way too long] title: “Mortality risk attributable to high and low ambient temperature: a multicountry observational study”.
The bottom-line finding, the take home message, might surprise even readers here at WUWT, quoted in the side-bar of the journal article:
Interpretation:
We report that non-optimum ambient temperature is responsible for substantial excess in mortality, with important differences between countries. Although most previous research has focused on heat-related effects, most of the attributable deaths were caused by cold temperatures. Despite the attention given to extreme weather events, most of the effect happened on moderately hot and moderately cold days, especially moderately cold days. This evidence is important for improvements to public health policies aimed at prevention of temperature-related health consequences, and provides a platform to extend predictions on future effects in climate-change scenarios. [extra emphasis mine – kh]
It is not extreme weather, not extreme temperatures, neither hot or cold, that cause the most temperature-related deaths:
“The underlying physiopathological mechanisms that link exposure to non-optimum temperature and mortality risk have not been completely elucidated. Heat stroke on hot days and hypothermia on cold days only account for small proportions of excess deaths.
“Discussion
Our findings show that temperature is responsible for advancing a substantial fraction of deaths, corresponding to 7.71% of mortality in the selected countries within the study period. Most of this mortality burden was caused by days colder than the optimum temperature (7.29%), compared with days warmer than the optimum temperature (0.42%). Furthermore, most deaths were caused by exposure to moderately hot and cold temperatures, and the contribution of extreme days was comparatively low, despite increased RRs [relative risks].
Our results suggest that public-health policies and adaptation measures should be extended and refocused to take account of the whole range of effects associated with temperature…”
The oft-repeated mantra of “global warming will cause more heat waves, extremely high temperature days, which kill more people” is simply not true — heat waves are not the big killer. Rather, cold days are the big killer – but not extremely cold days, as we intuitively think, but moderately cold days are responsible for the highest percentage of excess deaths due to ambient temperature. Equally true, it is not the extremely hot days that cause the bulk of high ambient temperature related deaths, but moderately hot days.
Read the study, [corrected now, h/t Griff and Les Johnson] it is short and accessible.
# # # # #
Anthony: I’ve updated the title and I thought it important to display this graph of results, thanks to reader “Greg”. From the paper:
More temperature-attributable deaths were caused by cold (7·29%, 7·02–7·49) than by heat (0·42%, ·39–0·44). Extreme cold and hot temperatures were responsible for 0·86% (0·84–0·87) of total mortality.
Odd statistics in that new graph – more people die of “extreme cold” in Thailand and Brazil than in Canada or Sweden. A global warming hazard for Canada?
Nick ==> Tricky little graph…the vertical dimension is “Attributable Fraction (%)”
Kip, I don’t see an issue with the y-axis. More of an issue is that they define “extreme cold” as a percentile of wherever you live. So it doesn’t matter whether the climate warms or cools; you’ll still have about the same amount of “extreme cold”. They have the same amount in Rio and Winnipeg.
I note that Australia, where I live, also has more deaths from extreme cold than Canada or Sweden (or Thailand). And it tells me that 6% of deaths here are attributable to “moderate cold”. The winters here are pretty mild. Their sole weather statistic is daily average; here I doubt that it has ever been below 5°C. So I think all they are saying is that here, as most places, winter is flu season.
Nick ==> Best to look at the .pdf file — their Figure 1 gives a better representation of the data.
Remember that this study is not part of the Climate Wars — these are public health researchers — epidemiologists — though their funding, which was from many sources depending on the researcher involved, probably depended on a climate change hook in the proposals.
It is an interesting look at the issue, for all of its epidemiological faults. (I am not a fan of modern day epidemiology being used in this way.)
Kip,
Yes, I looked there. I noted that in Bangkok, moderate cold is anything less than 25°C. And already at that temp there is substantially increased “cold” mortality.
Nick ==> Wierd, huh? I lived for years in the Dominican Republic, and if the temps got below 70F the locals came out in puffy jackets and ski caps…seriously!
“I doubt that it has ever been below 5°C”
You must live in Sydney. In Canberra, it can go down to -4 C in winter. In Thredbo & Perishers it goes somewhat lower.
“In Canberra, it can go down to -4 C in winter”
I’m speaking of the daily average, not the minimum. That’s what they used. But I have lived in Canberra, and been out and about in -10°C. That would pull the day average below 5.
But the study covered major cities, and I think the said three from Australia. Probably coastal.
“…winter is flu season.”
Well, Mr Stokes, isn’t that a surprise. Why is the flu season in winter? Because it’s cold. What does flu do? It kills people. So, because it’s cold, more people die.
I moved from North Dakota to Mesa AZ in 2007, presently in anything less than 50 F my wife digs out her North Dakota heavy coat and wool gloves. When she lived in Fargo and Watford City ND that was below zero clothing.
No one ever died from moderate cold per se. What happens is either it strains the heart, or you get sick. No one gets sick from it being too warm. That is hypothermia death are not the cause.
“No one ever died from moderate cold per se. What happens is either it strains the heart, or you get sick. No one gets sick from it being too warm.”
I think that is pertinent to the question. Cold puts stress on the heart, and cold is also the best time to catch viruses.
There was a documentary in the UK that explained it thus:
In moderately cold weather, it isn’t cold enough to rug up. So, here is Mr Traveler standing on the platform waiting for the train. And it is late, for whatever reason, as usual. So Mr Traveler is left there in the cold for an extra half hour & while he is waiting, the blood pools in his legs & forms small clots. Once he is back in the warm office, the blood clots dislodge & travel to the heart, lungs & other organs causing deep vein thrombosis.
And those statistics do not include the number of people that die in the world for carbon monoxide poisoning or fires due to improper heating during the winter. We get several of those reported every winter here. Entire families sometimes, which is very sad. Last winter a bunch of young people staying at a rural house with zero experience with the dangers of improper combustion and lack of aeration.
Javier ==> Yes, yes, and yes. CO is a deadly sneaky vicious killer, taking most of its victims in the middle of the night as they sleep. In the summers, we live in our camp trailer, with a propane furnace — a CO detector is an absolute must.
Are not the corks to deter flies from landing on the face?
Cold IS the enemy of all life. It kills whenever Man or beast have not prepared a protected den. Plants are in a near death dormancy, they cannot thrive nor feed the critters.
Yet the unthinking, touchy feely scientists and public want it to be our default “safe” direction. Woe to the world. GK
But cold weather is also caused by anthropogenic CO2, sayeth thee good book, thy IPCC 5th assessment report.
Interesting that Canada and Scandinavia have a relatively modest death rate from cold strongly supporting the finding that extreme cold is not a big factor. Jogged by – 25C mornings the previous several days, I suggest two things :first, in such weather, the air is calm and often sunny. I remarked to people I met as I walked with my grandson to school what a lovely day it was. Of course we were bundled up. Second, I believe we are fairly healthy folk and this must be a factor. I’ll be sampling my 80th year next year so I reckon I must be considered at higher risk than most but I feel unthreatened on the coldest day with no wind and the sun shining.
Hot days don’t seem to bother me either. I mapped geology in the Sahel of northern Nigeria for a couple of years and there was no air conditioning to come home to, explored for gold tin and diamond placers in Benin and Togo and opened a quarry and built a stone sawimg plant in Tanzania at the foot of Kilimanjaro. The worst was delivering the Winnipeg Tribune in 105 C in the late 1940s and beginning of the 50s, but then I went out to play with my friends afterwards.
The worst was delivering the Winnipeg Tribune in 105 C
Where in the world is twice as hot as death valley in August?
Winnipeg!
Reblogged this on Climate Collections and commented:
“Although most previous research has focused on heat-related effects, most of the attributable deaths were caused by cold temperatures. Despite the attention given to extreme weather events, most of the effect happened on moderately hot and moderately cold days, especially moderately cold days.”
I didn’t read the study, but I wonder if they adjusted for the school year? The “moderate cold” deaths just seem dis-proportionally high.
Kids go to school in the winter. As a consequence, they are exposed to all the germs of all the kids in the classroom. They bring those germs home, and pass them on to mom, dad and grandparents. Anecdotally, I noticed less colds and flu in the household once the kids were out of school.
Yes, there is a very good reason why the show “Survivor”, and any of the billion or so copycat shows don’t take place in any other place than the tropics: people would get hurt.
New scary headline: Global warming causes more moderately cold days and greater deaths.
According to the graph, only moderate cold is worth worrying about.
I’m certain there are at least two studies published before 2010 with the same results. It is strongly suggested that platelet adhesion and blood viscosity are factors. In the U.K., the Office for National Statistics has monitored “excess winter deaths”. Sorry I can’t get you further by typing on a piece of glass.
Josualdo:
Here one from 2000 by Keatinge e.a. over different regions in Europe:
http://www.bmj.com/content/321/7262/670.full
And one from 2001 about temperature related mortality in 11 cities of the USA:
http://aje.oxfordjournals.org/content/155/1/80.abstract
Thank you , Ferdinand. I remember it’s at least those two.
Just to add, the U.K. Data on excess winter mortality is accessible on the web.
Interesting study. It would also be interesting to determine correlation not only to temperature but to humidity and precipitation.
Hypothermia (exposure) is what kills people. Your body’s inability to produce heat faster than the environment takes it away will kill even hale and healthy military personnel. Your body doesn’t sense temperature it senses heat flux, how fast heat is entering or exiting. This is why room temperature certain objects (metallic objects for instance) feel “colder” than the surrounding items although they are all the same temperature. The “colder” objects merely are conducting heat away faster than the others.
Cold can be a nuisance, but cold and wet is down right deadly. If you are wet it doesn’t need to be even particularly cold for hypothermia to become an issue. An individual can die from hypothermia even on a temperate day.
Exactly so – 33 Degrees F is more dangerous than 20 below. Those who play in the cold extremes, like mountain climbers, know that snow is your friend.
Heat flow in and out of the human body is rather complex as there are numerous heat transfer mechanisms many of which only partially are determined by temperature. More are governed by the thermal mass and conductive properties of the air surrounding you as well as its ability to absorb more moisture and further evaporative cooling.
Bad news!
Arctic sea ice might reenter the normal zone before the end of this month:
http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/
Cold kills!
The lower than average ice of course has nothing to do with air temperature, as it’s below freezing. It’s just the warmer water from the late El Nino that delayed freeze up this year. But that excess warmth is unfortunately rapidly escaping to space.
Bite your tongue…everyone knows that warmth is not escaping to space but that energy is ‘energizing’ all those 400 CO2 molecules which in turn are radiating downward and further warming the arctic…jeesh how many times to I have to tell ya?
The Lancet paper is excellent.
Joe d’Aleo and I rewrote our previous paper on Excess Winter Mortality to include it:
https://www.friendsofscience.org/assets/documents/Excess_Winter_Mortality.pdf
Excess Winter deaths total ~100,000 per year in USA and ~10,000 in Canada.
The UK is very high at up to 50,000 per year. Many warm countries are very high too. This is avoidable.
The key is adaptation. Cheap heat, insulation, central heating, flu abatement, etc.
Best, Allan
Allan ==> Thanks for the link to your piece on this — the Lancet study is not new news, but this essay was prompted by Jane Brody’s highlighting the study afresh in the Health section of the NY Times earlier this week.
Hi Kip,
I’ve been writing about Excess Winter Mortality for several years – it is remarkable how wrong the warmists were about EVERYTHING.
Best, Allan
Of course moderate cold kills more than extreme cold. Extreme cold is very rare…that’s why it’s extreme. Tell me the probability of death during extreme cold/moderate cold/etc., not the % of deaths during those times. I’m sure the probability of death is still much higher during extreme cold.
https://youtu.be/HlTxGHn4sH4
So how would you call this? You think this would have any negative effects during moderate and extreme weather periods ? Isn’t cheap energy essential for a modern society ?
Hmmm…
The well known ‘excess winter mortality’ in the UK and elsewhere is frequently attributable to flu and similar winter season infections… which can cause excess (over other season) deaths even in mild winters.
See:
https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/deaths/bulletins/excesswintermortalityinenglandandwales/201415provisionaland201314final#causes-of-excess-winter-mortality
There is also pollution factor caused by temp inversions (but this may be offset by summer smogs?)
I’d say that this is not showing cold itself as the direct factor, while deaths in excess high temps are related directly to temperature….
“Griff December 21, 2016 at 3:22 am
I’d say that this is not showing cold itself as the direct factor, while deaths in excess high temps are related directly to temperature…”
Do you see how idiotic that statement is?
Compare cold climates with warm climates. It’s is rather strange that, more people live in warmer climates…which ARE directly related to temperature.
Griff ==> The whole issue, the point of the study, is focused on Public Health and how public health agencies can focus/refocus their efforts to lessen the impact of ambient temperature effects – particularly “excess deaths”. “Excess Deaths” is a peculiar public health epidemiological concept that may or may not have a physical reality, but, none-the-less they pursue it with enthusiasm.
By the global nature of their approach, the research team hoped to overshadow local effects to find a more general answer.
The study is quite short and can be read in 15 minutes or so.
Tom in Denver wrote:
“What’s interesting is that even in relatively warm countries such as Taiwan, Thailand & Brazil, the percentage of deaths by cold is still many times the deaths by Heat”
Indeed so. That would be explained if the actual cause of excess mortality from cold was something correlated with temperature rather than temperature itself. Obvious (negatively correlated) candidates are length of day or hours of sunshine, it generally being cold during the winter months when days are shorter, and also colder when there are fewer sunshine hours (typically in winter).
I live in Darwin, Australia. It’s bloody hot but we’ve had no air conditioning in our home for 15 years. You do adapt! -( although I’ve finallygiven up and have just put an air conditioner in the bedroom this year. ) Part of the key to adaptation is good house design – we have over 600 louvres and lots of ceiling fans.
The hospital occasionally sees people with heat related illnesses, – people who’ve had a fit in the heat and damaged their muscles more than if they”d been cold, people lost in the desert, or soldiers who’ve been forced to exercise too hard.
I only remember one cold-related injury – frostbite in a guy who fell asleep in a refrigerated truck full of beer!
Elderly people often can’t afford to run the aircon and sit inside in roasting houses – but for the most part don’t come to too much harm! Many people play sport in the heat of the day – the football season happens during the mornings of the hottest part of the year when we have temperatures of 35 degrees Celsius and close to 100 percent humidity, and lots of people ride bicycles in the day. There have been studies that show that cyclists in Darwin develop core temperatures that would be considered lethal elsewhere.
I think that everyone can adapt to higher temperate if given a year or so, and probably cold temperatures too. This is why studies about deaths during acute temperature changes are not applicable to longer term changes
Seems to me that many people would be apt to think, “It isn’t THAT cold,” and not wear sufficient protective clothing