Claim: Warmer Weather Reduces Birth Rates

This image shows women collecting water at a well in rural Burkina Faso, West Africa. CREDIT Kathryn Grace
This image shows women collecting water at a well in rural Burkina Faso, West Africa. CREDIT Kathryn Grace

Guest essay by Eric Worrall

A new study published by the US National Bureau of Economic Research claims that every day over 80F per year dramatically reduces your chances of getting lucky.

According to the NBER;

Maybe Next Month? Temperature Shocks, Climate Change, and Dynamic Adjustments in Birth Rates

Alan Barreca, Olivier Deschenes, Melanie Guldi

NBER Working Paper No. 21681

Issued in October 2015

Dynamic adjustments could be a useful strategy for mitigating the costs of acute environmental shocks when timing is not a strictly binding constraint. To investigate whether such adjustments could apply to fertility, we estimate the effects of temperature shocks on birth rates in the United States between 1931 and 2010. Our innovative approach allows for presumably random variation in the distribution of daily temperatures to affect birth rates up to 24 months into the future. We find that additional days above 80 °F cause a large decline in birth rates approximately 8 to 10 months later. The initial decline is followed by a partial rebound in births over the next few months implying that populations can mitigate the fertility cost of temperature shocks by shifting conception month. This dynamic adjustment helps explain the observed decline in birth rates during the spring and subsequent increase during the summer. The lack of a full rebound suggests that increased temperatures due to climate change may reduce population growth rates in the coming century. As an added cost, climate change will shift even more births to the summer months when third trimester exposure to dangerously high temperatures increases. Based on our analysis of historical changes in the temperature-fertility relationship, we conclude air conditioning could be used to substantially offset the fertility costs of climate change.

Read more:

The press release in Reuters;

Control over the climate at home might make a difference. The researchers suggest that the rise of air conditioning may have helped offset some heat-related fertility losses in the U.S. since the 1970s.

The paper’s title is about as lascivious as the National Bureau of Economic Research gets: “Maybe Next Month? Temperature Shocks, Climate Change, and Dynamic Adjustments in Birth Rates.” The researchers assume that climate change will proceed according to the most severe scenarios, with no substantial efforts to reduce emissions. The scenario they use projects that from 2070 to 2099, the U.S. may have 64 more days above 80F than in the baseline period from 1990 to 2002, which had 31. The result? The U.S. may see a 2.6 percent decline in its birth rate, or 107,000 fewer deliveries a year.

Just when you thought climate change policy couldn’t get any less sexy (PDF).

Read more:

The main paper is paywalled, but it seems bizarre to conclude that high temperatures reduce libido and birth rates, given that the highest birth rates in the world are mostly found in tropical countries. I can believe that an abrupt transition from cold to warm weather has an impact, warm weather can knock you about until you acclimatise – but to try to infer an absolute temperature scale from seasonal variations seems a bit of a stretch.

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November 3, 2015 5:58 am

negative feedback

Reply to  bobbyvalentine466921
November 3, 2015 9:38 am

They know wealth reduces birth rates.
They know wealth is a result of industrialization.
So they are aligning their prediction of what is known, but are dishonest about the cause.
They want poverty as a matter of political control.

Reply to  hugh
November 3, 2015 10:29 am

In fact, such a pattern might make evolutionary sense in terms of population maintenance.

Reply to  hugh
November 3, 2015 11:42 am

The poorer the nations the higher the birth rate, the greens might want to push UP the temperature !

Reply to  hugh
November 7, 2015 9:25 am

I don’t think they are dishonestly ignoring the cost. I think they are just, all to humanly, discounting it. I, who am not without sin, shall not cast the first stone. Too many brickbats and dead cats flying around, as it is.
Please allow me to praise them with faint damnation. We differ — radically — on cost-benefit analysis. And that really is about the ends justifying the means. I do not object to that, per se. People debate endlessly on whether the ends justify the means, and my conclusion is that all depends on the means — and the ends. And who gets to decide. And the fine print.
But they really think that the world will be a better place if they get their way. I disagree, of course. In philosophical terms, I think they are willing to squander what might be for what is.

george e. smith
Reply to  bobbyvalentine466921
November 4, 2015 10:50 am

When it’s cool you spend more time in bed.

Reply to  george e. smith
November 10, 2015 8:26 pm

Gee whiz, did you ever wonder why the climate wonks haven’t figured that out?

November 3, 2015 6:03 am

But…As the doomsters want to reduce the world population, isn’t it a win/win for their predictions?

Reply to  Kevin Lohse
November 3, 2015 6:49 am


Reply to  Kevin Lohse
November 3, 2015 8:31 am

Everywhere else, that is true. Environazis hate people.
When it comes to “climate change,” however, the rules change. Any differences are spun as scary.

Reply to  Kevin Lohse
November 3, 2015 10:41 am

There is no satisfying these people. You’d think they would cheer this news to the rafters. Maybe they got one eye on the falling global fertility rate since the 1960s.

Reply to  Kevin Lohse
November 3, 2015 1:41 pm

The Malthusians should be happy. You just can’t please some people!

November 3, 2015 6:04 am

Quick, tell Paul Ehrlich and the other anti-population folks!

November 3, 2015 6:07 am

Of course. This is precisely why tropical nations have such low birth rates compared to temperate climate nations. Wait a minute…

Reply to  Admad
November 3, 2015 6:09 am

Two minds thinking alike at the same time?

November 3, 2015 6:08 am

Is that why the birth rate in Third World African countries is so high?

Reply to  andrewmharding
November 3, 2015 7:33 am

The nights are too cold. Central heating helps reduce fertility rate.

Reply to  Hugs
November 3, 2015 9:47 am

Beautiful ! ! !

Reply to  andrewmharding
November 3, 2015 11:00 am

No, in most of the third world it is a response infant mortality. A sizeable fraction of that birthrate will die within months to a few years at most. As infant and child mortality reduces, birthrates go down. Average individual wealth is inversely correlated to birth rates and survivorship. The wealthier a society is on a per-capita level (the higher the average income) the low the population growth and the infant mortality rates are. That, BTW, suggests that the US is currently on the skids. Our infant and child mortality are increasing as individual wealth is reduced – to the point where we are now beginning to look just a bit third-worldish compared to the EU, Scandinavia and most of Eastern Europe:
You will find us in the lower middle of the pack between Serbia and Croatia. In fact we are only eight places ahead of Russia.

Reply to  Duster
November 3, 2015 3:01 pm

Like any big country – and the USA is seriously big from a UK perspective [how many times will the UK fit into Colorado? [One and a bit for the whole UK, including off-shore islands)
There will be variation.

Reply to  Duster
November 3, 2015 9:38 pm

In the US (except for the tiny number that were “supposed to be dead” and were therefore left in linen closets), any death after a live birth is an infant mortality.
Other countries, the child can die up to three months after being born alive – and they are not counted. (And there are a lot more that were “supposed to be dead” and therefore not counted either – such as in Holland.)

Ben of Houston
Reply to  Duster
November 4, 2015 6:39 am

Duster, that’s a widely known issue that’s based in definitions.
America doesn’t give up on many infants that it rightly should. Any baby that draws breath is considered a live birth, even if they are born at 24-27 weeks. At that age, even with infinite resources, you are going to have a high mortality rate (upwards of 50%) at that short a gestation period. I worked in the NICU for years, and a number of kids died. Most of them were critically premature, and all had severe congential problems, and would have died within the day in any prior century.
Most other countries consider this a miscarriage and do not count them. This is how America’s infant mortality is higher than Cuba’s.
To get an accurate comparison, you have to have accurate readings, and you will find that our late-term miscarriage rate is substantially lower than other developed countries.

Reply to  Duster
November 4, 2015 6:52 am

Oh, and back on topic, I think we all know that high birthrates are the result of high mortality. The rest of them were mocking the obvious problems with the study by taking it to the logical conclusion.

November 3, 2015 6:09 am

Margaret Stanger and Prescott Bush would both be warmers

Reply to  William E Heritage
November 3, 2015 6:12 am

typo: Margaret Sanger

November 3, 2015 6:17 am

Let’s see, both my kids were born in April. April – 9 = JULY !!! (for you Oz’ies, I live in the NH). Looks like my wife didn’t get the memo.

Paul Westhaver
November 3, 2015 6:21 am

In 1960 the pill was approved by the FDA for contraception (against conception). That is about the same time as Michael Mann’s hockey stick was apparently in full force.
Fake warming superimposed on fake hormones, with the reality of reduced birth rates among westerners, then the correlation is quite easily misrepresented as causation.
Sounds to me like the modern idea of science. BS piled on politics with the lure of money and depravity.
Aren’t we such advanced and objective creatures? Yes, we are gods aren’t we.
Thus spoke Zarathustra.

November 3, 2015 6:27 am

Birth rates have a lot to do with finances, the more money=fewer children except with Saudi royals.

Bruce Cobb
November 3, 2015 6:41 am

Sorry, I can’t read the rest now. I have a headache.

Reply to  Bruce Cobb
November 3, 2015 8:41 am

You probably got your headache from trying to figure out the meaning of so many long words. Decades ago, I noticed that people trying to appear smart would use obscure words. Often, they would use them incorrectly. This is a mechanism to make you think you are the stupid one. Do not be fooled by it.
I had to read the first sentence three times to figure it out. I have an exceptional vocabulary and consistently score much too high on IQ tests to believe I am the stupid one. These people are hiding something.
In this case, the fact that they are calling fertility good and the African birth rates are very obvious indicators that the whole paper is just publish-or-perish fluff.

Reply to  ladylifegrows
November 3, 2015 11:30 am

After reading this I would automatically conclude that India has a very cool climate.

Reply to  ladylifegrows
November 4, 2015 6:56 am

Not only that, but it makes no sense. This is clearly a dependent effect based on an uncontrolabe source (that being weather). The first sentence clearly suggests managing the birthrate using temperature control, which is just nonsensical.
I’ll agree, It sounds like it was written by someone trying to impress others but not knowing exactly what they are saying..

November 3, 2015 6:43 am

Fertility per woman is mostly income based — the higher the income, the fewer the children.
Play with the graph. Fun and educational.

Reply to  rovingbroker
November 3, 2015 6:45 am

and yet the birth rates have dropped in the US since the great recession.

Reply to  probono
November 4, 2015 6:57 am

It’s not direct or even correllated on small changes. The trend only is observable on large measures between social classes.

Reply to  rovingbroker
November 3, 2015 7:49 am

Browsing my ancestors has brought me similar picture. Women whose father was a high clerk had fewer children than those who were farmers, because social status requires you get a husband with high status. Those are not available so easily. The highest fertility was related to middle-low class, who got easily an acceptable husband. Low class women were often not married and didn’t have many children.
Of course, your experience may vary.

Reply to  Hugs
November 3, 2015 9:17 am

“Low class women were often not married and didn’t have many children.”
US version: “Low class women were often not married and have many children”.

Reply to  Hugs
November 3, 2015 11:22 am

The difference is single fatherhood is acceptable now in many countries, say in Iceland and Britain as an example, when 150 years ago it was not. So single parents, especially mothers have a higher social position and are not persecuted. That means relatively more children.
There is nothing wrong with lower class women having children. My own great-grandpa had two single grannies, and he married a single mother. Hard-working short Lutheran man, dry as a bone. All his children did well, even they couldn’t say they inherited anything more valuable than guts.

Stephen Skinner
Reply to  rovingbroker
November 3, 2015 7:54 am

Income and Education. Education provides other possibilities especially for girls.

November 3, 2015 6:53 am

The article claims that temperature spikes cause a drop in birth rate, therefore if temperatures go up permanently, birth rates will also drop.
Even a warmist should be able to spot the problem. People react differently to short term changes compared to more permanent changes.

DD More
Reply to  MarkW
November 3, 2015 10:00 am

214 Japan @ 8.07
212 Korea, South @ 8.26
211 Germany @ 8.42
203 Bosnia and Herzegovina @ 8.89
202 Bulgaria @ 8.92
200 Serbia @ 9.13
199 Hungary @ 9.26
198 Romania @ 9.27
197 Lithuania @ 9.36
193 Croatia @ 9.49
192 Poland @ 9.77
191 Latvia @ 9.79
191 Czech Republic @ 9.79
186 Belgium @ 9.99
185 Slovakia @ 10.01
183 Denmark @ 10.22
181 Canada @ 10.29
181 Estonia @ 10.29
180 Finland @ 10.35
179 Switzerland @ 10.48
177 Liechtenstein @ 10.53
164 Luxembourg @ 11.75
163 Russia @ 11.87
162 Sweden @ 11.92
160 Norway @ 12.09
These countries rankings of birth rates and are not noted for excessive hot days, so even the null-hypothesis is wrong.

Reply to  DD More
November 3, 2015 11:26 am

Oh you know nothing of the heat waves of Bergen!

Reply to  DD More
November 3, 2015 12:29 pm

According to Monty Python, Roman Catholics have a higher birth rate then Irish Protestant. What will be Gaians birth rate? My study suggest that it will be through the roof!!! High temperatures, lower income, shortage of food, power shortages if any power at all…..,and the list goes on…

Reply to  MarkW
November 3, 2015 3:10 pm

“Even a warmist should be able to spot the problem. People react differently to short term changes compared to more permanent changes.”
Poor bloody warmists need to be aware: –
Humans adapt.
Exactly as Mark states.
I am not sure whether this thread needs to advance.
OK – I’m pretty fed-up with our True-Believing-Alarmists.
Sea-level rise might [maybe] be 1.8mm/year.
That’s seven and a little bit inches [180 mm] each century.
I suggest that this rate of sea level rise – were it to continue unabated – can be managed by 99% of H. sapiens – easily!!

November 3, 2015 6:58 am

Now, whenever I read an article in the news that says “scientists have proven…”, “a new study shows…”, “research indicates…”, I roll my eyes and wonder how facts, data, and research have been twisted and contorted to support some predetermined end. While I understand that anecdotal observations cannot replace actual science, on the face of it, given the birth rates and populations in tropical climes versus colder ones, one really has to question this kind of pop science/research.

Reply to  kelleydr
November 3, 2015 7:22 am

The universal axiom of studies: Be skeptical be very skeptical.

Reply to  kelleydr
November 3, 2015 7:52 am

Reality is not the accepted proof of accuracy in the new science-politics-fear trifecta of global planners.
Only the spin in the press and the furtherance of the campaign determine which research is eligible for continued public-funded subsidies.

Reply to  kelleydr
November 4, 2015 7:15 am

They showed that hot weather (specifically hot days in summer) lowered birth rate. This could indicate that people do not have sex when uncomfortable. This doesn’t correlate to climate since we adjust to our climate. The new-normal days don’t feel uncomfortable at all, so there is no effect on birthrate.
It’s not that it’s a bad study. It’s just so blindingly obvious.

November 3, 2015 7:09 am

Do these “scientists” ever go out into the real world ??? All the hottest places on the Earth have OVERPOPULATION problems due to high birth rates !!!! Fracking nuts !!!

Reply to  Marcuso8
November 3, 2015 7:47 am

The authors are not scientists, they are not even “scientists”.
As it turns out, they are economists. They are not even average, every day economists.
Each one of them is an Ivory Tower Academic economist.
You can relax now.
And no, I do not think they get out much.

Reply to  TonyL
November 3, 2015 8:01 am

Economics is not considered a science ?????

Reply to  TonyL
November 3, 2015 10:05 am

@ Marcuso8:
NO! Not by me it is not. Not by a long shot.
I was going to add, that I thought they might be Keynesians as well, but then I thought that would be just cruel.
If anybody could match ClimateScience! people for a total disregard of reality, it would be Keynesians.

Reply to  Marcuso8
November 3, 2015 8:44 am

Well, now, to be fair, Africa has the lowest population density of all the continents except Antarctica.

Paul Westhaver
Reply to  Marcuso8
November 3, 2015 9:56 am

Population Density vs Continent
Continent Population Area in SQ Miles People per Sq Mile
Asia 4,140,000,000 17212000 240
Africa 995,000,000 11608000 86
Europe 739,000,000 3837000 193
North America 529,000,000 9365000 56
South America 386,000,000 6880000 56
Australia 36,000,000 2968000 12
Antarctica 4,000 5100000 0.001

Paul Westhaver
Reply to  Marcuso8
November 3, 2015 10:00 am

Population Density vs Continent

Continent————Population———–Area in SQ Miles———-People per Sq Mile

North America———529,000,000———9365000——————56
South America———386,000,000——–6880000——————-56

Reply to  Paul Westhaver
November 3, 2015 10:23 am

Two of my favorites:
Iceland land=39,770 pop=329,209 ratio = 8.3
Puerto Rico land=3459 pop=3,706,690 ratio = 1072
Lowest and Highest.
Puerto Rico most assuredly is a continent. It occupies it’s own tectonic plate and has it’s own continental shelf and continental slope down to the abyss.
Iceland probably arguably does not have it’s own tectonic plate, but is busy making one. So it is only a matter of time.

Reply to  Paul Westhaver
November 3, 2015 10:49 am

I know you are doing “continents” but the contrast between the “warm” US and Frozen Canuckistan is notable:
Canada – 3.87 per Sq Km in 2013 (2.4 in 1971)
United States – 34.56 per Sq Km in 2013 (22.5 in 1971) Canada has approximately one tenth the population of the US and 80% to 90% of the population lives within 100 miles (160 km) of the US border. (I am about 600 km North.)
The North American number includes Central America where the population density in 2011 was 32 per Sq Km (82 per square mile) compared to the US at 22.9 per Sq Km (59.3 per square mile)
From the everything causes everything department comes:
An interesting chart showing populations in Central America and all the warm Caribbean Islands. If you want to play with Correlation – it would appear warmth causes a higher birth rate. We know that isn’t why, socio-economic issues likely have more impact. But you could get someone to argue the case – either way.

Paul Westhaver
Reply to  Paul Westhaver
November 3, 2015 11:05 am

Hi Wayne,
I read some hysterical twattle above that Africa (the continent) was populated less densely than ALL other continents ‘cept Antarctica. So I checked it out. Really… who cares. I don’t get the “continent” as an appropriate means for division or comparison and/or establishment of boundaries. Anyway… like you said…”either way”

Reply to  Paul Westhaver
November 4, 2015 7:52 am

Paul, thanks for looking up the correction, but there’s no need to be smug about it. Someone can be wrong without being “hysterical twattle”

Paul Westhaver
Reply to  Paul Westhaver
November 5, 2015 9:00 am

Indeed someone can be wrong without engaging in hysterical twattle. I would also argue that someone who often is engaged in hysterical twattle, can be often wrong. Those two possibilities can be confused, unless one witnesses frequent hysterical twattle that is objectively wrong, also frequently. So, the context is time.

Reply to  Marcuso8
November 3, 2015 10:08 am

If the population of Africa is so low, then why are they all wanting to come here?

Reply to  dbstealey
November 3, 2015 4:15 pm

If by “here” you mean Australia,it isn’t just Africans who want to come here.

Ivor Ward
November 3, 2015 7:09 am

It is quite incredible that Alan Barreca, Olivier Deschenes, and Melanie Guldi would put their names to this tripe. It would take a matter of 15 seconds to look at the Wiki entry on fertility rates as I did to see that if there is any correlation, let alone causation, it is higher birth rates with higher temperatures.
Give them a dustpan and brush each and put them to something useful.

Reply to  Ivor Ward
November 3, 2015 6:16 pm

I would have thought that on this blog people would have understood that “long term warmth is compatible with high fertility” and “short spells of *unusually* warm weather are associated with temporarily reduced fertility” can both be true. The first is talking about conditions you’re acclimatised to, and the second about conditions you’re not acclimatised to. And the quoted material has the authors saying that people can adapt. (Like maybe yesterday was too hot to bother but tonight isn’t…) What’s objectionable about a claim that people can adapt?

johann wundersamer
Reply to  Richard A. O'Keefe
November 4, 2015 2:37 am

sure Richard A. O’Keefe
and why should somone name the obviously a ‘study’ and connect the now and ever obviously to a ‘projected’ maybe coming shock climate change visioned by super computer model magic wands.

November 3, 2015 7:21 am

Hmmm, at least in the US, the most popular birthdate is Oct 5th. Guess what was 40’ish weeks before that? New Years.
If one were to take this paper to it logical but absurd conclusion, that would have to be the cold day of the year, rather than the largest party day.

Tom in Florida
Reply to  RHS
November 3, 2015 9:31 am

Methinks it is alcohol that is the culprit.

November 3, 2015 7:33 am

so with the worlds population expected to reach 9 billion by 2050, must be cooler than we thought.

November 3, 2015 7:37 am

Our innovative approach allows for presumably random variation in the distribution of daily temperatures to affect birth rates up to 24 months into the future. We find that additional days above 80 °F cause a large decline in birth rates approximately 8 to 10 months later.

Wee p-values! Where are the Wee p-values? I am so disappointed, They do not show their Wee p-values. They found out so many new things, they must be sure! Or at least 95% sure.
They also did not make any sense at all in that blockquote.

Dubya Gee
November 3, 2015 7:48 am

I am going to have to do my own research on this. I will need multiple ‘research’ assistants as soon as possible. I don’t have any particular preference between blonde, brunette or redhead.
Results should be available within a year or so, depending on my survival. 😉

Reply to  Dubya Gee
November 3, 2015 8:03 am

LOL…what a way to go , sexed to death !!! ( for the good of mother Earth of course )

Reply to  Marcuso8
November 3, 2015 9:08 am

Death by snu snu. That is the correct term. 🙂

Reply to  Marcuso8
November 3, 2015 9:08 pm

One of many very funny episodes of Futurama.

Chris y
November 3, 2015 7:49 am

So birth rates have been plummeting since 1970.
CO2 concentration has been increasing since 1970.
The causation is dead certain- CO2 emissions reduce birth rates.
Extrapolation predicts that CO2 of 450 ppm will cause birth rates to go to zero.

Reply to  Chris y
November 3, 2015 12:14 pm

Brilliant! Then we become the Planet of The apes (if it’s not too hot)

Reply to  Chris y
November 3, 2015 12:15 pm

Brilliant! We become the Planet of the Apes (if it’s not to hot)

November 3, 2015 7:54 am

Can’t our government find a better way to spend our tax dollars? Better yet reduce spending!!
It seems as though any fool can get government funding if he links his stupid theory to global warming.
Our government is void of common sense.

November 3, 2015 7:55 am

Hey, when you are hot and sweaty already, what’s to stop them from having some fun? It’s getting hot and sweaty when they spend most of their time not hot and sweaty that puts many women off getting intimate.

Reply to  higley7
November 3, 2015 8:30 am

Higley, these women don’t get to choose. They are slaves of their husbands for the most part and refusal can bring punishment or banishment.

Reply to  Dawtgtomis
November 3, 2015 9:25 am

What? The women they studied lived in the US between 1931 and 2010! The photo of the African woman has nothing to do with the study.
Men don’t control when their wives are fertile and when they are not, either.
My questions-did the study take into account wars…when US birth rates would drop and rise due to soldiers being deployed and returning? The Depression? The advent of birth control? The rise in abortions?

Reply to  Dawtgtomis
November 3, 2015 4:22 pm

Oops, missed that, sorry. I was thinking third world women.

November 3, 2015 8:00 am

This reminds me of a poem a friend used to say…something about “When the frost is on the Pumpkin”…!

Donld Mitchell
November 3, 2015 8:22 am

I suspect that this is a study of correlation, not of causation. Correlations show up between the most unexpected pairs of things but they certainly do not imply direct causation. In this case, it might suggest that a medical study to find a possible causation chain such as reduced fertility in at least one of the sexes that could be caused by the hot days would be of interest. This correlation might have a correlation chain through behavioral patterns. This does not necessarily imply causation. For example, wet or icy roads have a correlation with vehicle “accidents”, but they do not cause them. They do offer expanded opportunities for people to cause vehicle “accidents” through unsafe driving. My opinion that this example is primarily behavioral is bolstered by my observational experience is that the more capable vehicles (for example 4 wheel drive vehicles–especially shiny ones with lots of chrome, big bumpers, and a winch) seem to be involved in a higher percentage of slick road “accidents” than dry clean road “accidents”.
Of course, as has been pointed out before at this web site, not all correlations have any direct (or even indirect) relationship with each other. For example, the older I get, the more intrusive government gets. Also, the older I get the larger our population gets. The population and intrusiveness may have a very definite relationship, but their relation to my age is sheer chance.

November 3, 2015 8:27 am

This claim actually has a basis in biology, however weak it might be. Overheating of the testicles is a well-known cause of temporary male infertility.
There might also be physical exhaustion preventing intercouse in extreme conditions but that is unlikely due to cooling off and resting during night hours and the peaking of testosterone in the hours following sleep.

Tom in Florida
Reply to  Dawtgtomis
November 3, 2015 9:34 am

Perhaps we should put our balls in boiling water just before as a natural method of birth control.

Reply to  Tom in Florida
November 3, 2015 4:29 pm

Hot idea. That could be the next craze after piercing.

Reply to  Dawtgtomis
November 3, 2015 4:26 pm

I wonder if kilts were designed with procreation in mind…

Jeff in Calgary
November 3, 2015 8:33 am

“temperature shocks” ? Really. Well this is some wishfull thinking.

Reply to  Jeff in Calgary
November 3, 2015 9:08 am

…Unless you’re a recently neutered brass monkey in Longyearbyen.

Tom Judd
November 3, 2015 8:36 am

The Spouse Default Swaps (STDs … oops, I mean SDSs) were supposed to compensate for any loss in activity amongst the Trading Partners. But those on the ‘street’ are claiming business is down. In response the Fed is no longer signaling a ‘tightening.’ Instead, the Fed will be ‘loosening’ the constraints on availability. That is, unless the market, once again goes into an orgy of “irrational exuberance.”
P.S. Doesn’t it seem like a contradiction in terms to have bankers perform a study relating to s.e.x activity?

November 3, 2015 8:43 am

From The Center for Biological Diversity …

The largest single threat to the ecology and biodiversity of the planet in the decades to come will be global climate disruption due to the buildup of human-generated greenhouse gases in the atmosphere. People around the world are beginning to address the problem by reducing their carbon footprint through less consumption and better technology. But unsustainable human population growth can overwhelm those efforts, leading us to conclude that we not only need smaller footprints, but fewer feet.
[ … ]
A 2009 study of the relationship between population growth and global warming determined that the “carbon legacy” of just one child can produce 20 times more greenhouse gas than a person will save by driving a high-mileage car, recycling, using energy-efficient appliances and light bulbs, etc. Each child born in the United States will add about 9,441 metric tons of carbon dioxide to the carbon legacy of an average parent. The study concludes, “Clearly, the potential savings from reduced reproduction are huge compared to the savings that can be achieved by changes in lifestyle.”

My bold.
Problem solved.

November 3, 2015 9:13 am

So, the authors don’t seem to understand what the word “fertility” means. Nothing in their study (not sure they understand that word either) even examines whether or not a woman’s fertility is affected by temperature change, but they continually refer to the “temperature- fertility” correlation. Idiots.

November 3, 2015 9:13 am

If this were true it would imply that nine months after the hot months would have the lowest numbers of births in the northern hemisphere. The Europeans seem to have the highest birthrates between March and July.

November 3, 2015 9:48 am

This must be true since there are so few people in countries that already are at that temperature range like China and India.

November 3, 2015 9:51 am

This will be balanced by all the extra babies that invariably follow power outages, following our shift to wind and solar.

November 3, 2015 10:08 am

Srga – it probably varies all over the world depending on culture and various other factors. In the US, there are lots of outdoor activities late into the evening. In the winter, perhaps there is a little more indoor activity:
“The biggest month
In 2013 more newborns arrived in August than in any other month. The second, third, and fourth most popular birthday months were July, October, and September, in that order”.

So month of conception in the US in declining order: November (Welcome to winter, Thanksgiving), October (Halloween) , January (Happy New Year), December (Merry Christmas).
Canada is slightly different:
“After averaging out the reports from the last five years, it seems this is the pecking order when it comes to birth months and popularity:
1. August 2. September 3. July 4. May 5. October 6. June 7. March 8. April 9. November 10. January 11. December 12. February “

Similar to the US but in Canada it looks like Summer Vacations and tailgate parties have an effect on the time of birth 😉
Below are the Australian records – which say September and October are the highest birth months.
However, the devil is in the details. There is actually not a lot of difference in the month to month numbers:

As one of the foremost practitioners of prenatal, newborn, baby, and family photography in Perth, we keep an eye on trends, such as the question in the title. Asking what month the most babies are born, though, is sort of a trick question. The short answer is that highest number of babies, both in WA and across Australia, are born in September and October.
However, those statistics are somewhat misleading, because there really isn’t any month that is more than 11.2% higher than any other month, according to the last reliable numbers, which were for births in 2009. The numbers are amazingly close:
January 24,316
February 23,646
March 25,202
April 24,949
May 24,854
June 24,852
July 25,769
August 24,383
September 25,760
October 26,272
November 24,235
December 25,042

NOTE: That means the most babies in Australia are conceived in the SH SUMMER – December and January. But as the writer noted, it may not be significant.
And I really doubt a variation of a couple of degrees will affect coupling – at least it doesn’t seem to from the Australian data.
Have fun with this, I don’t think it is a serious “threat”. 😉

November 3, 2015 10:11 am

I’m sure that there’s a report somewhere which says that warmer weather increases birth rate. It’s like rain, a warming climate causes draughts, a warming climate causes more rain, less wind, more wind, less snow, more snow, etc etc.

Gary H
November 3, 2015 10:17 am

So . . did the study bother to check to see if the US birthrate plummeted during the 1930’s heat-waves?
See EPA’s U.S. Annual Heat Wave Index from 1895 to 2014.

Gary H
Reply to  Gary H
November 3, 2015 10:36 am

Well – I probably should have looked first. actually the birth rate did take a dive. Oops. However, there was something else going on at the time (besides the dust bowl) – the Great Depression.

November 3, 2015 10:27 am

I’m not going to say all that much.
Since this is patently as daft as a box of frogs.
And anyway, as observed by both Nelly, in the appended popular song, and by oil industry analysts more widely:
“can’t nobody stop the juice, so baby, tell me, what’s the use?”
The U.N. should take note.
Of course, a rap song may only be an anecdotal account, but I would suggest that the relationships between temperature, clothing and propensity to engage in sexual activity are representative of wider observable trends.
And I am more than willing to conduct a more thorough and extensive research project on this topic…

Reply to  indefatigablefrog
November 3, 2015 11:57 am

less clothing, more kids. Gosh stop making sense. And good luck with your research 😉

Bill Parsons
November 3, 2015 10:43 am

Increased wealth also results in reduced birthrates. You have to wonder…
Meanwhile, a rather amusing bit released by NPR last week: Alaska is beginning to report benefits of warmth attributed to the longer growing season. This is a curiously positive story against that backdrop of environmental problems of a warming Alaska. If farming is as successful as this story indicates, a changing climate could signal one of the most profoundly positive changes in Alaska since their discovery of oil. Oil gave them the ability to import all their food at high prices. Expansion of agriculture on a vast scale opens up many possibilities, including self-sufficiency and even export, as they grow their own.

Meyers says the warming summers are a big part of his success.
“I hate to say that but I guess I’m taking advantage of the fact that it is getting warmer,” he says…
Meyers says he grew about 100,000 pounds of produce this year. Next year he hopes to double that.

“I hate to say that…” made me smile.
Burn him!

Berényi Péter
November 3, 2015 11:52 am

Oh, yess. Cool regions have the highest birth rate, warm ones the lowest. Not. image
Counterfactual thinking rulez.

Bill Adams
November 3, 2015 11:59 am

Professor Cole Porter, more than fifty years ago:
According to the Kinsey Report,
Every average man you know,
Will prefer to play his favorite sport
When the temperature is low.
But when the thermometer goes way way up
And the temperature is hot
Mr Pants
for Romance
Is not.
Cause it’s too darn hot, it’s too darn hot, it’s too . . . darn . . . hot.

Gary H
November 3, 2015 1:41 pm

Bonus – the video, “Watch Next: A Brief History of Global Warming,” plastered in the article is quite entertaining; for instance we learn that they predicted, 2001, that 21stc century warming will leave the 20th, in the dust, and that over the next decade – poof – sea levels started to rise.

November 3, 2015 3:45 pm

“Research claims that every day over 80F per year dramatically reduces your chances of getting lucky.”
Not if you have the best fossil-fuel powered air conditioning money can buy. Then your chances go up.

Reply to  Louis
November 3, 2015 6:34 pm

What about afternoon siesta?

November 3, 2015 3:54 pm

Doesn’t seem to be working in Africa…or India…

November 3, 2015 4:04 pm

Good. That’s what I call a “positive” feedback mechanism. There’s enough people on the planet.

November 3, 2015 7:55 pm

From what I’ve learned about global warming, population control is a big part of it. This ought to make the believers want more AGW…

November 3, 2015 7:55 pm

Why do people in Central America violate settled science? Don’t they listen to their betters?

November 3, 2015 8:10 pm

Well NH did have a miniature baby boom after being buried in snow for 6 months… but that could be correlated to a few other things….

November 3, 2015 11:37 pm

Well duhhhh…

Gary Pearse
November 4, 2015 4:59 am

I’m worried that I might be even more paranoid than the average skeptic here! I see this entirely in a different light. The big day of reckoning for failing Malthusians is virtually here: we are already 80 to 90% of peak population of 8 to 9 billion in the latter half of this century. There is no contest that economic development IS the “control knob”. This article is a brazen (they are getting more brazen- witness the transparently fraudulent pause buster, even to using well-known poorest quality data to cook the bust) attempt for global warming to get ahead of this parade before they miss the march entirely. These egghead elitist will have their fraudulent forecast borne out.

November 4, 2015 5:23 am

“Dynamic adjustments could be a useful strategy for mitigating the costs of acute environmental shocks when timing is not a strictly binding constraint.”
What does this mean?

November 4, 2015 7:05 am

Africans seems to have no problem reproducing. Central and South America have no problem reproducing. Philippines doe not have any problem reproducing. It is interesting that the places with the highest birth rates are also the hottest places on Earth, but climate “scientists” argue that heat will cause fewer births.
These “Scientists” retain stature far above what they have earned with far too many people.

November 4, 2015 9:35 am

So the new pickup line will be, “Hey baby, I have air conditioning!”

Aert Driessen
November 4, 2015 4:06 pm

So how come over-population problems are a feature of hot-climate countries? (India, Africa, SE Asia)

November 5, 2015 3:27 pm

I heard this one many years ago.
Those old PA Dutch farmers were’nt stupid.
“When da wedders hot & sticky
its not da time to donk da wikkie.
When da frost is on da pumpkin
dat’s da time wir wickie donkin”

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