- This topic is empty.
Viewing 1 post (of 1 total)
2023-01-01 at 17:41 #387787Nat QuinnKeymaster
This year ended with unusual cold in the USA and other parts of the Northern Hemisphere. There has been record cold at places all over America and Canada. Snow, ice, and blizzards have killed over 70 people in the USA – the New York city of Buffalo accounted for 37 of them. I have long predicted that, if the Sun remains quiet, there will be some global cooling, and the year 2100 will be about half a degree Centigrade colder than now. Does the snow and ice in America confirm my prediction?
No. The cold weather events in Northern America are no more a sign of global cooling than the warm weather events of the European summer were a sign of global warming. I was making a general prediction about the heat balance of the planet, not a detailed prediction about a particular region. It is impossible to make an accurate prediction more than a month in the future about any specific part of the world. What rainfall will the Western Cape have in 2025? I’ve no idea, nor has anyone else.
Will 2023 bring unusual heat or unusual cold to certain parts of the world? No idea. But I have got a very clear idea about global temperatures in the year 2100. They will not be more than a degree higher than now even if the Sun becomes active again, and they will be slightly lower than now if she remains quiet. Why my confidence in one prediction but complete lack of confidence in the other? Let me explain.
Studying the climate
There are two different considerations for studying the climate of the planet Earth. The first is extra-terrestrial, the exchange of energy between the Earth and universe outside. The second is terrestrial, the distribution of energy on Earth, among the land, air, and water. The latter is far more complicated.
By far the most important source of energy for the Earth is the Sun. The Sun radiates us with heat in the form of electromagnetic radiation (X-rays, light, infra-red, radio waves, and so on) peaking in light. A very small source of heat comes from the Earth’s interior, from residual heat and heat from radioactive decay. The heat balance of the Earth depends on the heat reaching the Earth and the heat leaving it. Heat might be absorbed in the atmosphere or pass through it. Heat might be absorbed by the Earth or reflected from it.
Greenhouse gasesabsorb radiant energy leaving the Earth in the atmosphere. The most important is water vapour. Carbon dioxide (CO2) is a minor greenhouse gas, although a vitally important biological gas for life on Earth. Its concentration is usually given in parts per million (ppm) – parts of CO2 compared with parts of all other gases in the air.
When multi-celled life began, about 550 million years ago, CO2 was at over 4,000 ppm or over 0.4%. It is now about 430 ppm or 0.043%. CO2 absorbs infrared radiation up to about 150 ppm but not beyond that. In the last 550 million years, CO2 has never been seen to have any effect on global temperatures. So, none of the recent changes in temperatures can be attributed to changes in CO2. Man has increased CO2 from about 280 ppm in the 19th Century, and temperatures have risen by about 1 degree C in this period, but this is coincidence as temperatures were higher a thousand years ago when CO2 was lower than now.
The most critical terrestrial factor for the Earth’s climate is low clouds (cumulous), which reflect away more heat than they absorb, so cooling the Earth. When the Sun has high electromagnetic activity, there are fewer clouds and the Earth warms. (The likely mechanism has been intensely studied.) This explains the warm periods over the last ten thousand years. When she was very inactive, we had the horrible cold of the Little Ice Age (LIA), about 1300 to 1850 AD, with terrible weather extremes, much worse in severity and frequency than in the present era.
The distribution of heat on Earth, in the air, land and seas, is much more complicated, and much more difficult to predict – indeed mathematically impossible to predict. There are a few tendencies. For example, the colder the climate is, the more extreme weather there is. This is because climate change hardly affects the equator at all but does affect the higher latitudes, so that a cold climate increases the differences between the equator and poles, driving stronger winds. Otherwise, we don’t know much at all.
We know what El Nino and La Nina are (changes of surface temperatures in the tropical Pacific) but we don’t know what causes them or exactly what effects they have on regions far from them – the Western Cape for example. The Sahara Desert was quite recently a wet savannah inhabited by hippos and elephants. Why did it change into a desert? Nobody knows. Dropping temperatures? Perhaps, but why should they? Nobody knows. Sometimes in the middle of a cold spell, you get record high temperatures, such as happened in Australia where temperatures reached 51.7 deg C at Longreach in 1901 and 53 deg C at Cloncurry in 1889. Similarly, there was snow in Egypt and Syria in 2013.
Furthermore, there are important oscillations in ocean flows and temperatures. Since the oceans hold far more heat than the atmosphere, these have profound consequences for our climate. I have mentioned El Nino and La Nina, or the El Nino Southern Oscillation (ENSO), which has huge influence on local climates. Then there is the Atlantic Multidecadal Oscillation (AMO) and the Pacific Decadal Oscillation (PDO). The PDO has a 60-year cycle (30 years of warming, 30 years of cooling), and now seems to be in a cooling phase. Could this have anything to do with the cold northern winter? Maybe but we don’t know.
Heat and cold
One thing, though, is certain: the cold is far more dangerous than the warmth. Unusual cold kills about 20 times more people than unusual heat. Humans evolved in the equatorial heat of Africa and can cope with heat much better than cold. I am scared of the cold.
I have been in the middle of the Sahara and in the edge of the Antarctic. The latter frightened me more, beautiful though it was. I was in England in December 2010, and marvelled at the snow that seemed to cover the whole country, but was scared by it. (In 2000, Dr David Viner, a scientist at the Climatic Research Unit of the University of East Anglia, closely related to the IPCC, predicted that, “Children just aren’t going to know what snow is.” To be fair to him, though, this was no worse than the silly predictions right now of the Earth warming by 3 deg C or the oceans rising by metres.)
What to do? First, we need to use science and reason to address the climate, not superstition and propaganda. Mankind might be doing some bad things to the environment but we are not causing dangerous climate change. We need to study the science, data, facts, and records that show this clearly, and then communicate them to the politicians and the public. Second, we need to acknowledge the dangers of natural climate change and prepare ourselves for them.
Down the ages, bad weather has caused famines, floods, storms, wars, revolutions, and reversions to horrible superstitious practices such as witch-hunting. The American winter has shown us that extreme weather can happen any time. We need to have resilient energy sources that can keep people warm and functioning throughout the blizzards and snowfalls. This means forsaking the very expensive but utterly useless “renewable” energy (solar and wind) for grid electricity in favour of nuclear, gas, and coal. Our airports need to be equipped for cold weather. (In 2010, I found out that the airports of London and Paris were shut down by a bit of snow but those in Moscow kept functioning under much more snow.) In parts of South Africa prone to floods, such as KwaZulu-Natal, we need to be constantly prepared for floods. There is no mystery about what needs to be done.
The climate of the last hundred years has been generally benevolent, productive and peaceful, with less extreme weather than the previous few centuries. I expect this to continue on the whole. The problems of 2023 will not come from the climate but from politics. For some reason I cannot explain, countries worldwide seem to be cursed by the most stupid politicians in history.
England and America have the most hopeless political leaders I have ever known in my longish life. South Africa’s political leaders have managed to wreck almost the whole of our economy despite the massive bounty that nature has bestowed upon our country. We live on a wonderful planet, in a period of equable climate, inhabited by potentially decent and intelligent human beings. But our political leadership is woeful. How can we correct this?
Viewing 1 post (of 1 total)
- You must be logged in to reply to this topic.