By Ian Bradford
All scientists and many non-scientists would agree that there is climate change. Climate change has been occurring for millions, in fact billions of years — and nearly all of it without any human influence.
Now suddenly, according to the climate alarmists, humans are responsible for climate change, even though Carbon Dioxide levels have reached as high as 7000ppm in the past. They are at a very low 410ppm at present. What used to be called global warming was changed to climate change because from 1998 the earth has actually cooled slightly, though the cooling has increased in recent years, especially in the northern hemisphere. The cooling was an embarrassment for the climate alarmists.
Climate change covers anything. Let’s start with a definition of climate from NASA:
“No weather event by itself is evidence of global warming/climate change as the test is whether the weather adds to new weather pattern over many years or even millennia.”
So a couple of days rain causing flooding is NOT climate. Heat waves and droughts need to go on for years at least. So these are weather events.
Natural processes which cause climate change
The sun is the major influence causing climate change. But there is another important influence and that is the ocean currents-namely the Gulf Stream.
Variations in the Sun’s Intensity: The suns intensity varies over an 11 year cycle. The variation is about 0.1%. Even this small fluctuation can affect the earth. The earth orbits the sun in paths which are approximately elliptical. The path can vary slightly. Sometimes the earth is a little further from the sun and sometimes closer. This affects the climate. Obviously, when the Earth is further from the sun it is not as warm on the earth. The Earth can be warmer or colder.
The diagram show the exaggerated elliptical orbit of the earth around the sun
The shape of the ellipse changes over a period of 100,000 years. This means the Earth can be closer or further away from the sun. So it can be warmer or cooler.
The larger changes affecting the Earth occur at regular intervals. These changes are called the Milankovich cycles. They affect the amount of solar radiation striking the earth. The Earth orbits the sun in paths approximately elliptical. These changes in the Earth’s orbit occur over 100,000 years and this coincides with the glacial periods.
- The shape of the Earth’s orbit is the Eccentricity.
- The angle the earth’s axis is tilted with respect to the earth’s orbital plane is the Obliquity.
This has varied between 22.1 and 24.5 degrees. This cycle spans about 41,000 years. Obliquity slightly alters the distribution of solar radiation across the planet. As obliquity decreases, it gradually helps make our seasons milder, resulting in increasingly warmer winters and cooler summers.
The direction the earth’s axis is pointed is the Precession. As the earth rotates, it wobbles slightly on its axis. This wobble is due to tidal forces caused by the gravitational influences of the sun and moon. This cycle lasts about 26,000 years. Axial precession makes seasonal contrasts more extreme in one hemisphere and less extreme in the other. It also changes the timing of the seasons.
Diagram; Wikipedia Commons. Author: NASA, Mysid.
The top diagram shows the Tilt of the Earth’s axis, (the obliquity), and the lower diagram shows the wobble of the axis, (precession).
Variation in Sunspots
The number of sunspots on the sun’s surface varies from year to year. The variation is cyclical and a cycle takes about 11 years on average. This variation was observed by German astronomer Heinrich Schwabe in 1843 and is called the Sunspot Cycle or Solar Cycle. The largest number of sunspots gives a solar maximum and a period of few sunspots gives a solar minimum.
In 1989 we had 157 sunspots and this dropped to about 9 in 1996. Between 1700 and the present there have been 24 solar cycles. Solar Cycle 24 began in 2008. In some years in the Maunder Minimum, there were no sunspots. Each time the sunspot count rises and falls, the magnetic field of the sun reverses polarity. So a return to the original polarity takes 22 years on average.
We are now in Solar Cycle 25 and it continues the weak sun pattern of Cycle 24.
Valentina Zharkova, mathematician and astrophysicist at Northumbria University in Newcastle UK, published an editorial supporting the argument that with Cycle 25 the sun had entered a new minimum phase. She said this would reduce the solar activity and reduce the sun’s magnetic field. She said this would reduce the Earth’s temperature comparable to the Maunder Minimum. (The Maunder Minimum was the coldest part of the Little Ice Age. The Maunder minimum went from 1645 to 1715.)
In 2019 the sun saw 281 spotless days corresponding to a 77% reduction and at the start of 2020, the reduction was 78% and if this continued then the number of spotless days in 2020 would be more than in 2019. She considered that the increase in cosmic rays entering the Earth’s atmosphere would lead to the formation of more clouds, and this would lower the earth’s temperature. Cosmic rays form aerosols in the upper atmosphere which seed clouds. The reduction of the sun’s magnetic field lets more cosmic rays enter the Earth’s atmosphere.
Zharkova predicted that the new solar minimum would last till 2053 and reduce the Earth’s temperature by 1 deg C. (It was a reduction of 1.4 Deg C in the Little Ice Age). Sunspot data from 2021 confirmed Zharkova’s hypothesis.
The Gulf Stream
The Gulf Stream originates in the Gulf of Mexico and takes warm water from the tropics into the Northern Hemisphere.
For reasons I won’t go into here, if the Gulf Stream slows or even stops, then the Northern Hemisphere will cool significantly. Scientists have confirmed that in recent times the Gulf Stream has indeed slowed. This is probably reflected in the RECORD LOW temperatures experienced in the Northern Hemisphere winters over the past three years. These are never mentioned on TV, only the heat waves of recent times. The heat waves are nothing to do with humans, but are caused by the formation of heat domes — a natural phenomenon.
The impact of volcanoes on climate
A large cloud of ash can stop the sun’s radiation from reaching the earth, and so cooling can occur. When Mt Pinatubo erupted in the Philippines on June 15th 1991, an estimated 20 million tonnes of Sulphur Dioxide and ash particles blasted more than 20km into the atmosphere.
The most significant climate impacts from volcanic injections into the stratosphere come from the conversion of Sulphur Dioxide to Sulphuric Acid which condenses rapidly in the stratosphere to form fine sulphate aerosols. (Note: just above the Earth’s surface is the troposphere, then just above that is the stratosphere).The aerosols increase the reflection of radiation from the sun back into space, cooling the Earth’s lower atmosphere or troposphere.
The Pinatubo cloud was the largest Sulphur Dioxide cloud ever observed in the stratosphere since the beginning of such observations by satellite in 1978. It caused what is believed to be the largest aerosol disturbance in the stratosphere in the 20th century. It cooled the earth’s surface for about three years following the eruption by as much as 0.8 º C.
Pacific climate influences: El Nino and La Nina
During normal conditions in the Pacific Ocean, trade winds blow west along the equator taking warm water from South America towards Asia. To replace the warm water, cold water rises from the depths.
El Nino and La Nina are two opposing climate patterns which break these normal conditions. Scientists call these phenomena El Nino Southern Cycle (ENSO). During El Nino, trade winds weaken. Warm water is pushed back East towards the West coast of the Americas. El Nino can affect weather significantly. La Nina has the opposite effect of El Nino. Trade winds are even stronger than usual pushing more warm water towards Asia.
Both El Nino and La Nina can have global impacts on climate. They can lead to droughts, heavy rains and flooding, wildfires, high temperatures, and strong winds. Of course, weather events due entirely to El Nino and La Nina cannot be blamed on humans putting more CO2 into the air. Both El Nino and La Nina are natural weather events.
Here is what the Sydney Morning Herald wrote about El Nino and La Nina in November 2021
The Bureau of Meteorology declared on November 23 that a La Nina event was in full swing, with climate scientists saying it would bring cooler temperatures, more rainy days, and higher risks of extreme weather.
The La Nina is likely to hold until at least January, and weather experts are warning the increased rainfall will heighten the chance of flooding, with soils already saturated and rivers and catchments full. In fact, it’s already shaping up to be the country’s coolest spring since 1999 and the wettest spring since 2011.
Eastern Australia is vulnerable
As a giant island, Australia cops weather from all directions. One of the main drivers of our weather, particularly for those living in eastern parts of the country, extreme conditions periodically roars out of the Pacific. Whether it’s an El Nino bringing extreme droughts or a La Nina whipping up severe tropical cyclones and floods, farmers and firefighters and almost everybody else have cause to keep a wary eye on subtle temperature changes in the waters to Australia’s north-east.
The impact of El Nino and La Nina on weather should not be under estimated. When El Nino produced high temperatures in 2015, climate alarmists were quick to label it as one of the hottest years in recent times and put it down to humans putting Carbon Dioxide and Methane into the atmosphere and hence causing global warming. It was nothing to do with humans, but simply a natural event caused by El Nino.
The distinction between Climate and Weather
We might say the Siberia has a cold climate. That goes on from day to day and year to year. Superimposed on this it rains, snows, blows etc. This is weather.
It is likely that the heavy rain and flooding experienced in New Zealand recently is caused by the same El Nino and La Nina affecting Australia.
Natural factors cause the climate changes
Carbon Dioxide and Methane do NOT cause global warming/climate change nor any adverse weather events. The bad news is that the sun is in a period of very low activity and scientists have confirmed that the Gulf Stream is slowing. Looking at the past, many scientists are predicting that we may be going into another Little Ice Age. Below is a predicted temperature anomaly graph for the slowing and possible stopping of the Gulf Stream.
The dark blue indicates that the temperature will drop by 8ºC. Now, because the Gulf Stream may stop altogether, there will be a build-up of warmer water from the equator south. So in future years New Zealand may escape the very cold that the Northern Hemisphere may experience.
The prediction from the graph is that NZ will either stay the same, or warm by about 1ºC. However, the sun is also a factor, and if the number of sunspots continues to keep low then we will experience the cold. Make the most of the warmth that may be coming, it may not last.