Adding heat to COVID
Sunrise over Hamilton - photo by Susan Wortman
Hamilton has just entered its fourth heat emergency of 2020 and it may be a long one, a relatively gentle reminder that parts of the planet are already hitting temperatures where humans can’t survive. Current forecasts predict plus 30C daytime temperatures for at least the next week, at a time when the pandemic has knocked out many of the city’s cooling centres at libraries and recreation centres.
The only library branch open at this point is Central on York Boulevard. And only two of the city recreation centres can be used although several public pools are scheduled to re-open on Monday. In lieu of this, the availability of spray pads is being emphasized, but these may not be very useful to the seniors whose health is most vulnerable in heat waves.
Globally there is accumulating evidence that we are in the middle of the hottest year ever. Both January and May came in with record average monthly temperatures, while the three months in between each reached second hottest status. June’s numbers are not yet available.
Earth’s polar regions continue to heat up far faster than the rest of the planet. Recent studies conclude that melting in the Arctic and Greenland is now occurring six times faster than in the 1990s. And 2020 has seen unprecedented heat waves in both the Antarctic and the Arctic. A record 18.4 Celsius was reached in early February at one of the Antarctic research stations. Three days later that was smashed when the mercury hit 20.75C at another station.
Those records were set during the southern hemisphere summer. Even more eye-popping numbers are now showing up in the ice fields of the northern hemisphere. On June 20 the Siberian town of Verkhoyansk, deep inside the Arctic Circle, hit 38C (just over 100 Fahrenheit). Last week it was Canada’s turn when the village of Alert in Nunavat near the northern tip of Greenland recorded its highest ever temperature.
The pandemic has largely pushed climate news out of the public eye, but that hasn’t prevented atmospheric carbon dioxide levels from pushing past 415 parts per million this spring with multiple consequences for global heating. Perhaps most sobering was a May study that found dozens of locations where temperatures had exceeded our upper survival limits.
“Humans’ ability to efficiently shed heat has enabled us to range over every continent,” acknowledged the authors, “but a wet-bulb temperature of 35°C marks our upper physiological limit, and much lower values have serious health and productivity impacts.”
Climate models had predicted this situation wouldn’t be reached until mid-century, but the study identified thousands of times on five different continents including along the US Gulf coast where these intolerable combinations of heat and humidity have been exceeded.
“Humidity is more dangerous than dry heat along because it impairs sweating – the body’s life-saving natural cooling system,” noted one news report. “Even the strongest, well-adapted people cannot carry out ordinary outdoor activities like walking or digging once the wet bulb hits 32C, though most would struggle well before that.”
Heatwaves can be deadly at much lower temperatures, especially when prolonged and when there is no significant night time relief. In the United States, heat waves kill more people each year than all other natural disasters combined, and especially devastate low income communities of colour. This year the state of New York is installing 74,000 air conditioners in the homes of low-income seniors.
The World Health Organization says 166,000 people have died from heat waves since 1997. More than a third of those perished during Western Europe’s 2003 extended bout of extreme temperatures.
