An Inconvenient Thermostat

I’m standing on the corner, watching all the toques go by–what my American friends call ‘stocking caps’–not to mention the ski jackets, gloves, and scarves. Attire appropriate for the temperature if not the season. Six months ago in Ottawa — in what should have been leaf-peeping season — it already felt as if the Big Chill were just around that corner.

I attracted a few sidelong glances as I waited for the light, but no one said anything or even stood too close. There’s nothing foolhardier than accosting or otherwise annoying a woman wearing a sundress and sandals, outside, on a chilly mid-October day.

My internal thermostat functioned fine for nigh-on 50 years. It was set a little high, maybe, but operated consistently. Like an oven whose gauge always reads low, once you get onto it you can make allowances. It got a little flaky over the last few years — nothing that would cause you to throw out a previously reliable performer, but unsettling nonetheless. Given the options, I learned to wear readily removable layers to adjust the thermal load, minute by minute.

Now my thermostat is just plain silly: completely useless, really, oscillating wildly from one extreme to the other for no apparent reason, and providing no decent indication of the ambient temperature. As for controlling internal temperature, well, forget that.

They can transplant hips and kidneys and ream out clogged arteries: it seems odd that they can’t replace or even conduct basic maintenance on a clearly malfunctioning system. But it is so: I’ve checked with my doctor. Half a generation younger, she encourages me to hang on. What I’m hanging-on for is not clear. When I raise the subject, every 60-something woman I know looks pained, avoids eye contact, and mumbles less-than-convincing assurances: things get better. Sort of.  

Enough. It’s time to bring in the scientific top guns. With deadly and expensive-to-treat diseases competing for funding dollars, I know that hot flashes won’t rate unless they’re linked to something with big political impact. From a public policy perspective, what could be bigger than climate change?

Mainstream scientific thinking has missed the link between hot flashes and global warming, but consider the United States Environmental Protection Agency’s website. According to the National Academy of Sciences, the Earth’s surface temperature has risen by about one degree Fahrenheit in the past century, with accelerated warming during the past two decades. There is new and stronger evidence that most of the warming over the last fifty years is attributable to human activities.

Human activities, indeed — and note that telling phrase about the acceleration of warming during the last two decades. Can it be coincidence that these two decades have also seen the first wave of menopausal Baby Boomers?

Canadian women aged 50 to 59 outnumber those in their 60s by more than 50%; those in their 70s by 200%; those in their 80s by a whopping 360%. Even allowing for some, well, drop-off with age, relative cohort size is clear and won’t change anytime soon: today, 40-somethings outnumber 50-somethings by more than 20%.

So we have a statistical basis for the acceleration noted by the National Academy of Sciences. What of the causal link between hot flashes and surging temperatures worldwide? What we need first is an estimate of the subject population, and then a quantification of what they are subject to.

World population can be rounded down to six billion for calculation ease. Using Canadian population proportions and adjusting downward again (not all countries experienced such a dramatic post-WWII baby boom), we can conservatively estimate that 10% are in the years of prime interest: their 50s. About half are female, which gives us three hundred million women subject to the most intense hot flash phase.

Assuming that each woman suffers an average of five flashes daily, each of which raises body temperature by five degrees Fahrenheit for five minutes — conservative estimates all, according to my surveys — the total heat produced per woman per day is 125 degree-minutes, an astounding annual total of more than thirteen trillion degree-minutes, worldwide.

The right question isn’t whether this amount of heat can account for a paltry one degree Fahrenheit increase globally in a century, but how it can possibly fail to. Only a scientific community caught up in adolescent competition between theories about greenhouse gases and solar activity could have overlooked this relationship. However, it’s never too late for sound research.

Rigorous investigation will be required to validate the causal link and determine whether it’s a self-limiting problem. We’ve all seen those seriously senior ladies wearing sweaters in July, victims not of hot flashes but of a perpetual chill. As the population ages, maybe the Boomers will move from being net heat producers to heat consumers, thereby counteracting the last fifty years of steady warming. What a relief that would be, both for us personally and as concerned global citizens.

Once the problem is properly defined, researchers can look at corrective action. Even if they can’t cure the symptom — if hot flashes are to women what baldness is to men — maybe we can get something out of it. With half the Boomer cohort undergoing temperature swings totalling trillions of degree-minutes annually, why not generate electricity from the resulting mini thermal gradients? It’s an emission-free and only-too-renewable source of power. And its safety? Well, just don’t stand too close to the generator in the sun dress on the corner, and you’ll be fine.