By Dr Graham Pinn
Heat or cold, it’s always climate time!
As yet another, supposedly,” unprecedented” summer comes around, sensationalising social media look to create another crisis; in reality, the heat is nothing new. Working, or exercising in a hot climate, without adequate fluid or electrolyte replacement, can lead to problems, problems which have been known since the beginning of time.
The current emphasis is always on climate change, with fictitious melting icecaps, the destruction of the Great Barrier Reef, sinking Pacific Islands, and extinction of polar bears, all indicating the end is nigh. A factual assessment shows that both temperatures and carbon dioxide levels have, in the past, been higher, without our world coming to an end. In climate reality, we are nearing the end of an interglacial period, between ice ages; these typically last around 10,000 years and relate to the planets orbit and solar activity; the next ice age is coming!
Summer time is hotter than winter, in some parts of the world extremely so; living in Germany for many years, the summer temperature could sometimes reach 30C, in the winter minus 20C. Needless to say, the organised locals had appropriate clothing and housing for both situations. Worldwide statistics show that around 5 million die from extremes of temperature annually; European statistics from over 800 cities, show that cold-related deaths outnumber heat by ten to one; as cold kills far more than heat, a warmer world will save lives!
In Australia, where extreme cold is uncommon, there is a small but significant resulting loss of life, a survey by Peden et al in 2023, showed hypothermia deaths rising from 8 in 2015, to 37 in 2020-21, this particularly affected the elderly, living in cities. Is this due to climate change, or an increasing number of seniors; maybe they are unable to afford the cost of renewable electricity supplied heating? Hypothermia can still occur in air temperatures as high as 10C, and in water temperatures as high as 20C.
As well as the elderly, children are also more vulnerable to cold, their low body mass to surface area, means they lose heat more rapidly and core body temperatures can fall dramatically. From personal experience, I managed a child who survived unscathed, after 30 minutes under cold water, with a rapid temperature fall producing a physical hibernation, protecting against brain damage. Warming has to be done with care, as critical irregularities of heartbeat can occur at around 30C, on the way to the normal 37C.
At the other end of the spectrum, according to UN chief Guterres, as we move from global warming to global boiling, there should be more cases of heat stroke.
A far less impressive graph of the same annual data, over 100 years
The Australian Institute of Health and Welfare reported 2150 heat-related hospital admissions over the 2 years, from 2019-2021; one third in the over 65 group. The commonest problem is heat-syncope, due to inadequate fluid or electrolyte replacement, typically with exercise, leading to low blood pressure and fainting; heat cramps are also caused by the same mechanism. Normally, adequate fluid replacement by mouth resolves the problem.
The next stage is heat-exhaustion, where cooling by sweating is overwhelmed and the temperature starts to rise; this is associated with additional symptoms such as headache, confusion, rapid pulse and breathing. Treatment with intravenous fluids is usually required. Women are at a disadvantage in the heat, they have fewer sweat glands, which do not produce so much sweat, meaning they are less able to control their temperature by its evaporation.
When the body temperature climbs to 40C plus, this is an emergency known as heat stroke; as well as exposure to excess heat. Consequences include muscle breakdown, kidney and liver failure, heart disorders, brain damage and ultimately, death. Vigorous cooling is required, externally with ice-baths, internally with cooled fluids, sometimes even with kidney dialysis.
The typical circumstance for heat-stroke is excess or prolonged exercise, with inadequate fluid and salt replacement, in a hot climate; there are however other explanations. It can occur with an infection and fever, particularly when associated with fluid loss from diarrhoea or vomiting.
It can also occur with exercise in milder climates, when excess or inappropriate clothing prevents heat escape. From my own medical experience, this was an occasional occurrence on military exercises in Europe, when wearing carbon- coated suits, known as “noddy suits”, to prevent biochemical poisoning; organ failure and even death, resulted Those who believe this is a far-fetched scenario, should read about the use of chemical weapons in the Middle East, in Iraq and Syria.
Back in the real world, we are once more heading for summer and “weather porn” is upon us. The year 2023 was initially rated as the hottest year on record, in Australia it was eventually downgraded by the SRC to the 8th hottest year on record. Old recordings are discounted as unreliable, but the evidence is there that current temperatures are nothing new, the hottest accepted temperature was 50.6C at Chester Hill in 1909. Other temperatures, such as 53.9C, recorded by explorer Charles Sturt, in 1828 are ignored.
Long term records show current temperatures are the same as 1000 years ago.
Having lived in the Pacific and Indian Ocean Islands, (neither disappearing with climate), I can confirm that, even in the Tropics, people can survive without air conditioners, or electric fans, by using some common sense. The most common approach, in the Mediterranean as well, is to take a siesta during the hottest part of the day.
September 2024 was apparently the driest ever recorded, followed by wide-spread flooding later in the year! CSIRO tells us that rainfall on the continent has not altered over 100 years, cyclones are decreasing in frequency, bushfires have not increased, and the great barrier reef remains in rude health. Despite fire-risk not increasing, the fire service has added to the heat-tension by changing fire risk classification from low/medium/high, to medium/ high extreme and catastrophic.
As the population has quadrupled over the last century, worldwide deaths from extreme weather events have fallen by 98%! Such facts will not stop the usual summer media onslaught about “unprecedented” temperatures. At the end of the day the looming problem is not heat, but availability and cost of electricity; unreliable and expensive renewable energy is affecting the ability, to both cool and heat our homes! By comparison, as winter looms, those countries which have just been cut off from Russian gas supplies by Ukraine, really do have a temperature problem!
Dr Graham Pinn is a retired Consultant Physician.