I took this photo two years ago as I was building our cabin at Red Lake. It was June 19. I was finding it difficult to continue work. I kept getting dizzy, sick to my stomach and in a brain fog. This wasn't the hottest day in particular. There were many like it.
In the shade over by the dockhouse, it wasn't nearly so hot, probably 32 C or so. But I wasn't working in the shade nor could I. New home construction isn't done under a big tree. You can say the same about farm work, road work, fishing, tree planting or any other outdoor job. You have no choice but to be out in the sun.
I don't remember the heat index for this particular day but frankly, it didn't matter. That is because the heat index is calculated for the shade. It is derived from the temperature on the thermometer in the shade combined with the relative humidity. The more humid it is, the higher the heat index.
We cool our bodies by sweating and this works best when the air is dry. You can't sweat at all in a bathtub.
By comparison, the wet-bulb temperature is calculated by the temperature on a thermometer (in the sun) wrapped in wet cloth and also takes into account the wind speed. The greater the wind, the better the evaporation that cools off the thermometer (and our bodies).
Research shows that humans will die in six hours with a wet-bulb temperature of 35 C. And that would be for a person laying naked, in the rain, with hurricane-force winds blowing over him. If you were standing up or moving around --activities that generate body heat -- the fatal temperature would be more like 32 C.
At 37 C wet-bulb a person would die in minutes.
The wet-bulb method of calculating the temperature more accurately reflects the effect of hot weather on the human body.
I have just become aware of wet-bulb temperature from a book I'm reading: Five Times Faster by Simon Sharpe.
I will undoubtedly have more to report about this book later but in essence, Sharpe says we have all under-estimated the dangers of climate change because we have been looking at it the wrong way. And by we I mean the scientists who study it and the governments they inform. And of course, us, the citizenry.
Our error comes from predicting what will happen rather than doing a risk assessment. He offers examples of the difference between the two but I'm going to make up my own here.
Let's say I have loose lug nuts on the front wheel of my car and I drive it 50 km to Thunder Bay anyway. I can predict with near 100 per cent certainty that the front end is going to shake. There is about a 50 per cent chance that the wheel will wobble so badly that it enlarges the stud holes in the rim and ruins it. There is a bit less of a chance that this single trip will ruin the tire itself. Finally, there is a chance that either the wheel falls off completely or the car just becomes unsteerable and leads to a crash.
What's the worst that can happen? That's what a risk assessment is. Well, the worst is that the vehicle crashes and kills people either in my vehicle or in other vehicles or just standing along the road. Maybe they are kids waiting for the school bus. That is the worst case scenario.
Now that I have done the risk assessment I can figure how to avoid the worst. In this case, I could just tighten the lug nuts. The risk of killing someone isn't worth the probability that the wheel might stay on the whole trip.
We haven't done a risk assessment with climate change. We have been making predictions about what will happen, not what could be the worst. So let's just say it: the worst is that the world becomes too hot for humans to survive or to grow our food.
The wet-bulb temperature information above shows we aren't too far away from the worst.
We have already seen so-called heat waves that have killed people. More than 600 died in British Columbia a couple of years ago. This is Canada! It is one of the coldest-nations on Earth.
Coincidentally I just happened to see a realty company's listing for some property near ours on Red Lake where they inform buyers of the risk of climate change for this spot. They list it to be at Significant Risk. It currently experiences seven days of 29.1 C and that is expected to rise to 28 days of 32.6 C by 2050.
Insurance companies do risk assessments, especially for their own industry. What's the worst that can happen for them and their customers? They become insolvent. That is why they only take a 0.5 per cent chance.
And that is why they have stopped insuring buildings in Florida, California and many other places that are experiencing repeated weather-related catastrophes.
You can find real-time wet-bulb temperatures on the Windy.com website or app. I strongly advise everyone to get this app and learn how to use it. Your life may depend on it.
Another is Zoom Earth. You can set this to show you where the forest fires are, again, in near-real-time. This is the stuff we need to know to survive now.
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