6. Causes of Climate Change

We keep hearing ever more about Climate Change, through the news, articles, books, and even blockbuster films. But despite these discussions, broad scientific consensus, and hard-won political victories, we have not changed our trajectory towards global temperatures rising above levels most scientists agree would be catastrophic. As we all head towards this future, in this long-read we explain a little of the history of climate science, why it is so important for us to understand the difference between annual and cumulative emissions, and why climate change is so integrated with our Great Transition. We will also include an overview of a new scientific concept to the causes of climate change, which would suggest a fundamentally different strategy for how to address it. What we hope is the 4Waves approach will really help us to understand just why a real solution is all but impossible.

What is Climate Change?

First of all, what is climate change? By climate, we mean the average weather conditions at a global level over a longer period of time. It includes everything from average temperature in different seasons, the amount of rainfall and sunshine, and the chance of extremes. The global climate was more-or-less stable for over 12-thousand years since the end of the last ice age. It is this climatic stability which many believe made the previous Great Transition, the transition from a hunter-gatherer to an agricultural society, possible. However, in the 20th century, this climate stability was disturbed, and this disturbance is called Climate Change. The most obvious characteristic of this disturbance is rising atmospheric greenhouse gas concentrations and average global temperatures since the beginning of the 20th century.

Until the 1970s, very few were concerned with climate change, and since then, its causes have been the subject of many years of debate. Many theories for Climate Change were discussed: the influence of solar activity, cosmic dust, the movement of the Earth's poles, natural processes, volcanic activity, and more. However, by the 1980s, scientists agreed that the main cause is the anthropogenic factor, that is, human activities emitting greenhouse gases and destroying forests by a third of pre-industrial levels. Particularly convincing is the tight correlation between increasing greenhouse gas concentrations and increasing global average temperatures. This is now the generally accepted concept for Climate Change among scientists today.


Climate change involves many changes and processes, a rapid rise in average temperature in all climatic zones of the Earth is just one of many, albeit an important one. Other changes include melting glaciers in high-mountainous regions, the Arctic, Greenland, and Antarctica; rising sea levels due to the rising temperatures causing both (a) water thermal expansion and (b) melting glaciers; more frequent natural disasters such as droughts, floods, and hurricanes; the migration of bacteria, viruses, and diseases; Ocean acidification and deoxygenation, a decrease in the concentration of oxygen in the ocean; an impact on crop yields; and much more.

Research into the relationship between the gases forming the Earth’s atmosphere and the climate began in the 19th century. Scientists studying the Earth’s atmosphere were not thinking about the cooling or warming of the planet, but they gradually came to understand how the Earth’s atmosphere is formed of various gases and that these gases absorbed heat. This understanding helped them discover how changing amounts of carbon and water vapor in the air could change the temperature of the planet. This is now known as the Greenhouse Effect. Without naturally occurring greenhouse gases, the Earth's average temperature would be around -18°C instead of the much warmer 15°C. Water vapor accounts for nearly two-thirds of this effect, CO2 for nearly a quarter, and CH4, N2O, and O3 for most of the rest.

We now understand the following about the flow of heat from the sun to the Earth and then back into space. Photons from the Sun come to the Earth’s surface, heating both the land and the ocean. The Earth’s surface then starts to emit or radiate thermal photons back out to space. Greenhouse gases let solar photons from the Sun through, but actively bind to thermal photons. Part of these captured heat photons are re-emitted back to the Earth’s surface. Increased greenhouse gases in the Earth’s atmosphere lead to more thermal photons re-emitted back towards the surface and the near-surface temperature rising.


99.9% of the Earth’s atmosphere is formed of just three gases; nitrogen (78%), oxygen (21%), and argon (0.9%). The remaining 0.1% is formed of multiple other gases, including greenhouse gases, the largest of which is carbon dioxide. When carbon dioxide concentrations rise and air temperatures increase, more water vapor evaporates into the atmosphere. This amplifies the greenhouse effect. So while carbon dioxide contributes less to the overall greenhouse effect than water vapor, scientists have found that carbon dioxide has a disproportionately large impact on global temperatures. Carbon dioxide controls the amount of water vapor in the atmosphere and thus the size of the greenhouse effect.

Based on radiocarbon analysis of ice formed over the past 800,000 years in Russia's Vostok station in the Antarctic, we can see that during that time the concentration of CO2 has remained around about 280 ppm (0.028%). In fact, many scientists believe these concentrations have been stable for closer to 3 million years. Today carbon dioxide has reached almost 420 ppm (0.042%).

In 1958, the first measurement of atmospheric CO2 concentration in Mauna Loa observatory, Hawaii was 315.34 ppm. In 2020 in May, the peak of the year, it was - 417.1 ppm https://www.esrl.noaa.gov/gmd/webdata/ccgg/trends/co2_data_mlo.png

In 1896, Swedish scientist Svante Arrhenius published the first calculations that a doubling of pre-industrial atmospheric CO2 led to an average annual increase of 4.95°C in the tropics and just over 6°C in the Arctic, very much in line with the latest computer models.

Already by the beginning of the 20th century, human activity as a result of the Great Transition of just the 1st Wave had become significant enough to influence the balance of greenhouse gases in the atmosphere. An English engineer, Guy Stewart Callendar, showed that in 1938 carbon dioxide concentration levels were 10% above long-term levels. While he too theorised this could eventually influence world temperatures to rise by 2 degrees, he certainly did not predict the speed with which it would happen. But even these projections were not treated seriously by even the scientific community. Then from 1958 onwards, US scientist Charles David Keeling, provided some of the most precise measurements for the historical baseline of carbon dioxide concentrations and for the recent increases. Keeling’s first measurements at the observatory Mauna Loa in Hawaii showed 315.34 ppm. He theorised that global temperatures would rise much sooner than previous scientists had projected. But only in the 1980s did the scientific community more broadly accept that human activity could and was indeed influencing the concentrations of greenhouse gases to the point that it could increase global temperatures.

Science also tells us that the global climate goes through cycles influenced by the tilt of the Earth towards the Sun. This is the cause of the last Great Ice Age, for example, that covered Europe and North America and then receded. The warming following that ice age is what allowed humanity to flourish. However, it is now happening much faster. Over the last 80 years or so global temperatures have climbed 1 degree Celsius, roughly ten times faster than the average rate of ice-age-recovery warming. Moreover, this global figure hides the fact that in some places the increase is far higher. In the Arctic, northern Canada and Russia, for example, temperatures have risen close to 2.5-3 degrees celsius. Rising temperatures in the far North particularly concerns scientists as it increases the risk of extreme events that could radically worsen the situation. These include the release of methane due to the melting of permafrost (tundra) and methane hydrate bombs in the ocean. A single such emission could exceed the annual greenhouse gas emissions!

Following the scientists’ lead, world leaders by the late 1980s were also starting to act. In 1984, there was a US Congressional Hearing, after which the term “global warming” was adopted and the severity of the warming threat was recognized. In 1989, the Intergovernmental Panel for Climate Change under the United Nations was established. In 1992, the first global climate convention was held in Rio de janeiro; it was there that the term Sustainable Development was adopted. And in 1997 the Kyoto Protocol was agreed. But Kyoto failed. The Kyoto Protocol aimed to decrease annual greenhouse gas emissions by 5%. By 2012, when the Kyoto Protocol finished, global emissions had increased by 54%. As Vaclav Smil calculates, in the 25 years following Kyoto, emissions from coal rose 70%, from crude oil by 37%, and from natural gas by 83%. Worse, emissions from the production of ammonia rose 60%, pig iron by 90%, and cement by 230%, The annual registration of cars nearly doubled and airplane deliveries increased by almost 150%!

Since December 2015, we have a new agreement, the Paris agreement. But even if it is successful, it aims merely to keep temperature increases to between 2.8 and 3.2 degrees higher by 2100. This is despite years of scientists explaining that even 2 degrees would be disastrous.

Over time scientists have also come to understand that different gases absorb different amounts of heat photons, what is now known as Global Warming Potential. Carbon dioxide forms the basis of Global Warming Potential. In other words, the Global Warming Potential of a gas is the amount of heat absorbed by any greenhouse gas in the atmosphere, as a multiple of the heat that would be absorbed by the same mass of carbon dioxide (CO2). One molecule of carbon dioxide captures one heat photon, while a molecule of methane captures 28 heat photons. Other greenhouse gases can capture far higher amounts, for example, nitrous oxide captures 300 photons of heat and certain f-gases around twenty thousand photons. In other words, certain gases play a significantly more important role in global temperatures than their relatively small amount in the Earth’s atmosphere might suggest.

As mentioned, while concentrations of f-gases are too small even to be measured in millionths, they are very potent. Their contribution to Climate Change is still limited but steadily increasing; from 0.5 % in 1990 to 0.8 % in 2004 and 1.4 % in 2016. Their contribution is expected to continuously increase in the near future, because of the amount of time they remain in the atmosphere. In some cases, f-gases will remain in the Earth’s atmosphere for more than 1,000 years.

In 2017 we saw the following emissions: CO2: 41,226 Mt, CH4: 367 Mt, N20: 10.8 Mt, and F-gases: 0.294 Mt. If we use the Global Warming Potential coefficients to calculate their proportional impact, then we will see something closer to this graph:

If we use F-gases as an example, in 2016 greenhouse gas emissions were nearly 50 Gt, so F-gases CO2 equivalent emissions were around 1Gt.

Human Responsibility

Some protest that humanity has added relatively very little carbon dioxide to the natural carbon cycle. They argue that natural carbon emissions are huge. This is true. In the natural carbon cycle at the end of the 20th century, around 210 Gt of carbon per year was emitted; 60 Gt by plant respiration, 60 Gt from the soil (microbial respiration and decomposition), and 90 Gt from the ocean. But the same amount is utilized by Earth systems: 120 Gt by plant photosynthesis and 90 by ocean. In other words, the planet naturally removes as much carbon from the atmosphere as it adds.

Cellular respiration and photosynthesis are direct opposite reactions while photosynthesis requires carbon dioxide and releases oxygen, cellular respiration requires oxygen and releases carbon dioxide. Oxygen is consumed while carbon dioxide is released in plant respiration at night. In dim sunlight, the Photosynthesis rate equals the respiration rate. A plant consumes all the oxygen photosynthesis generates. It also uses all the carbon dioxide this respiration creates.


While humans’ carbon emissions may be relatively small compared to the natural carbon cycle, “only” an additional ~10 Gt of carbon (~36 Gt of CO2) or 5% per year, but this is “excess” carbon. Only part of this volume (55%) is absorbed by the Earth's systems. So far, land plants and the ocean have taken up about 55% of the extra carbon people have put into the atmosphere while around 45% has stayed in the atmosphere. Eventually, the land and oceans will take up most of the extra carbon dioxide, but as much as 20% may remain in the atmosphere for many thousands of years. This excess carbon in the atmosphere is enough to generate planetary warming. On another note, excess carbon in the ocean also makes the water more acidic and less oxygen, putting marine life in danger.

250 years of the Great Transition and Global Emissions

Humanity has produced greenhouse gas emissions for a long time, burning wood for heating and cooking, burning forests to obtain new territories for settlements and agriculture. But it was with the beginning of the Great transition that a significant increase in human greenhouse gas emissions began. As we now well understand, from previous long-reads, the 1st Wave countries saw tremendous changes to the societies and economies in the 19th and 20th centuries as they transitioned from agricultural to urban industrialized societies.

If we look at the emissions today, we can see the following: human activity emits 4 types of greenhouse gases – carbon dioxide, methane, nitrous oxide, and so-called F-gases.

Source- IPCC, 2014. Based on global emissions from 2010 (https://www.epa.gov/ghgemissions/global-greenhouse-gas-emissions-data)

If we start with carbon dioxide, the main source is the combustion of hydrocarbons such as coal, oil, and natural gas, or technologies based on the combustion of hydrocarbons for energy production. As we saw in the energy long-read, from the end of the 18th century and throughout the 19th century, 1st Wave countries burned coal exclusively; in metallurgical plants, in steam engines, for cooking and heating a growing number of houses, and so on. Then at the end of the 19th century, electrification began. Coal and oil products were burned in the furnaces of power plants to provide electricity and heat for the growing 1st Wave economies. At the beginning of the 20th century, 1st Wave countries began creating a new source of carbon dioxide emissions, burning of petroleum products, the basis of the transport revolution and motorization of the world. Internal combustion engines were used not just to power cars, but tractors and combine harvesters, airplanes, and ships. Already by the early 20th century, CO2 concentrations in the Earth’s atmosphere had increased above their 800-thousand year or possibly 3-million-year norms of 280 parts per million or ppm. Almost all those emissions came from 1st Wave countries.

Another source of CO2 emissions not included in the graph above is Land Use Change (LUC), including deforestation (when people cut down trees, this leads to a decrease in the absorption of atmospheric CO2, which is not an explicit emission. In 2019, CO2 emissions were 43 Gt CO2 (or 12 Gt of carbon (C), including 36.81 Gt from fossil fuels and industry (mostly cement production) and 6.23 from deforestation and other LUC.


Methane, or CH4 concentrations, have risen to their highest concentration in at least 650,000 years and cattle and manure as the largest source of emissions. Food production increased dramatically during the 19th and 20th centuries. Among other things, these production increases brought with them huge herds of methane emitting cattle, from 500 million heads in 1900 to 1.5 billion heads in 2018. Cattle produce methane as part of their digestive process and emit the gas via burping and flatulence. Rice cultivation surged, which produces methane, as waterlogged paddy fields provide an ideal environment for microbes to produce methane in a process called ‘methanogenesis’. After World War II, rapid increase in natural gas usage to generate electricity more efficiently as well as to heat homes and for cooking meant more methane emissions. While burning natural gas emits CO2, natural gas is methane and leaks of this methane occur during the exploration, production and transportation of oil and gas. By the beginning of the 21st century these are the largest sources of methane emissions.

Sources of nitrous oxide emissions include agriculture, energy use, industrial processes, and waste management. The largest source is agriculture, particularly nitrogen fertilizers production and the use of fertilized soil and animal waste. Since the 1960s, nitrogen fertilizer use has shot up, helping feed the growing population. Increased numbers of livestock also increase animal waste, which is often over-applied on cropland. Humanity today contributes 5 times more nitrogen to the soil than in the natural cycle of the planet.

Finally, despite being relatively small in volume, F-gas emissions have an outsized impact, as they are the most active greenhouse gases. Chief among these emissions are refrigerants, which are used in car air conditioners, industrial and residential refrigerators, air-conditioners and even tennis balls! And as we mentioned in our urbanization long-read, we can expect F-gas emissions to increase dramatically in the near future, also due to the doubling or tripling of urban populations in tropical regions buying cooling devices such as fridges and cars with air conditioners.

Where things go from here

Greenhouse gas emissions are integral to, if not the unwilling side effect of, the technologies and methods that allow humanity to move to an urban industrialized society. It is the inevitable byproduct. Before the mid-20th century, almost all global emissions could be attributed solely to the Great Transition of 1st Wave countries. Then, in the middle of the 20th Century, 2nd Wave countries began their transition. They used the same technologies and strategies developed in 1st Wave countries. They too started to burn coal, build cities, see their populations rise, eat more and more varied diets, and so on. 2nd Wave countries, which today include 3.5 billion people, thus saw new, rapid increases in emissions; and those emissions still continue to rise. India and 3rd Wave countries (2 billion population and another 500 million expected) began their transition in the late 20th century, while 4th Wave countries (1 billion population and another 3 billion expected) are only just beginning now. And as we can see from our long-reads on Food and Energy, we can expect demand for food and energy to double this century. Annual emissions are rising and do not appear to be reaching their peak. And even if we begin to reduce our annual emissions, something which is absolutely required to reach net zero emissions, we will still be emitting billions of tons of greenhouse gases for many decades to come, increasing our cumulative impact on the atmosphere.

The Great Transition looks set to add ever higher concentrations of greenhouse gases into our atmosphere. We have already emitted 1.5 trillion tons of CO2 emissions alone since the start of the transition (so called cumulative emissions), and we have already seen temperature increases above 1-degree Celsius. If we want to keep temperature increases below 2 degrees Celsius, we have around 590 to 1240 gigatons more from 2018 levels. That is in total, not per year, but in total. This is known as an “emissions budget”. However, at current rates of 35 gigatons a year we will exceed that amount by the middle of this century. If we want to keep temperature increases below 2 degrees Celsius, we have around 590 to 1240 gigatons more, a number we would reach by the middle of this century. Even though 2 degrees is often touted as a target, as explained, that would already be a disaster. Temperatures have risen today by around 1-degree Celsius, and we are already witnessing a large number of events caused by climate change, such as forest fires in Australia, France, and California or hurricanes on America’s Atlantic coast. Further increases would lead to exponentially more dangerous changes. And as we can see, we are not even on target for 2-degrees.

When seeking to explain the choice in the 1st Wave countries, climate activists often present policy ideas that call for reducing annual emissions in 1st Wave countries. Such activists present the costs as financial, for example investing in renewables and lifestyle changes; not flying, for example. This would no doubt be helpful, but it is quite far from a solution. It fails to address the most important aspect of climate change – emissions, as we have seen, are cumulative. The 1st Wave countries have already emitted those 1-trillion tons of Co2 to urbanize 1-billion people. The climate is already broken, and the citizens of 3rd and 4th Wave countries are still in the early stages of their transition. Reducing emissions in the 1st and 2nd Wave countries may be feasible, but what about the 6 billion people in the 3rd and 4th Wave countries, including the 3-billion yet to be born, that have yet to complete their Great Transition to an urban industrialized society? Their emissions far exceed the remaining budget of emissions before exceeding 2-degrees.

When looking at the following graph, we should remember that in 1950 it would have been almost entirely made up of 1st Wave countries. Today, one 2nd Wave country, China, alone is responsible for 12% of cumulative missions, mostly from the last 30 years.

Of our total human cumulative 1.5 trillion tons of CO2 emissions between 1750 and 2017, again the 1st Wave accounts for 1 trillion tons. The 2nd Wave, so far, has emitted 450 gigatons, the 3rd Wave 70 gigatons, and 4th 10 gigatons. Understanding that the countries of the 2nd to 4th way have yet to complete their Great Transition, that is 6-billion people, we can expect emissions to continue to grow. If those 6-billion were to emit the same amount per capita as the 1st wave, that would be an additional 6 trillion tons. And 1st Wave countries’ emissions will not disappear overnight.

If we look at cumulative emissions over time we can see the initial rise of examples of 1st Wave countries (e.g. EU-27, US), followed by the 2nd Wave (e.g. China), the 3rd Wave beginning to rise, and the still low 4th Waves.

4th Wave countries form less than 1% of cumulative emissions (around 10 gigatons), as we have seen, increased energy consumption, food production, etc. will soon see this rise rapidly.

An Alternative Perspective and its Implications

Normally, this is where the explanation of our impact on the climate would stop, and we would move to explain how these trends appear to be set to continue. However, it would be a great disservice to our readers. Instead, we need to explain that there are other ways that humanity may be damaging the climate, aside from greenhouse gas emissions. The Earth's climate system is an extraordinarily complex and still poorly understood system. Another explanation for climate change is that it comes as a direct result of the destruction of natural forests. Russian theoretical physicists Viktor Gorshkov and Anastasia Makarieva have been working on a theory for 60-years called the “theory of biotic regulation” recently covered by the journal Science.

In this theory, forests are not simply carbon sinks, they actively regulate global temperatures. Forests are living organisms, biota, formed of everything from soil bacteria to microorganisms in swamps, soils, and so on. Gorshkov and Makarieva posit that these biota actively regulate global climate. This is done through two means. Firstly, Gorshkov and Makarieva argue that forests actually pull moisture from above the oceans into the heart of continents. This phenomenon is known as Forest Biotic Pump, some scientists call it “Flying Rivers”. This is what prevents those areas from turning into deserts, maintains the water level in rivers and groundwater, and feeds mountain glaciers. In this way, forests regulate the global ocean-to-land moisture circulation. Secondly, forests are able to regulate cloud build-up and height. While we still poorly understand whether clouds increase or lower temperatures, there is agreement that they play a role and that forests generate clouds. In other words, by influencing the distribution of moisture in the atmosphere on a continental scale and by regulating cloud build-up, forests are able to lower temperatures. For more information, please see https://bioticregulation.ru.

Forests in this understanding can be compared to a super-computer created by nature, the work of which we still poorly understand. Forests themselves "know" whether it is necessary to cool the air around or not. Therefore, a significant reduction in the area of the world's forests has led to the fact that forests have become worse able to cope with the function of regulating global temperature.

The key point is that the climate is damaged, due to humanity’s destruction of 50% of ​​the world's main natural forests in Siberia, Canada, the Amazon, Congo, and Oceania. As we discussed in the long read on food, over the past 200 years, growing food production as a result of increased agricultural lands has come at the direct expense of forests. Without those forests and their ability to regulate global temperatures, even bringing human emissions to zero would not be enough. We would need to restore natural forests and increase their area by 50%, or about 1-trillion trees. What is also important is that planting or mass-seeding trees is not reforestation. Human planted forests are not able to replicate this role. The forests must regenerate on their own, we need the so-called a-forestation. And before we can restore forests, we need to prohibit all logging except in man-made “plantations.” This long-read would be too long if we went into detail about all the ways humanity uses wood and the increased usage of deforestation as part of the Great Transition. Suffice it to say, the Great Transition sees growth in forest clearing for livestock to wood and cellulose used in everything from the furniture industry to packaging, newspapers to toilet paper, and more. And, as we have already understood, in the 21st century we have to radically change many industries!


So our global annual emissions are increasing and it will be very hard to decrease annual emissions, because humanity will see another 6 billion people move from an agrarian to an urban industrialised society by 2100. For the same reason, we can see the world’s remaining wild forests come under pressure. Scientists have informed us of the very severe consequences of a 2 degree increase in temperature, but we look as if we will increase temperatures by at least 4 degrees. We can therefore expect to see ever greater conflict between the 1st Wave and the 3rd and 4th Wave countries over the issue. 3rd and 4th Wave countries will not give up on their transition, especially not due to requests from 1st Wave countries who have already emitted what they needed to complete the transition. Regardless, there is no feasible scenario of humanity willingly sending itself back into the agrarian era. In our next long-read, we will consider why new clean technologies are not yet available to allow the 3rd and 4th Wave to complete their transitions emission free or with far lower emissions.

Sadly, there is little cause for optimism. The impact of climate change will gradually become ever more apparent and destructive for humanity. Many have started making comparisons to the Roman Empire. It took more than 300 years to collapse, and only descendants were able to establish the moment of the beginning of the end. The people who lived at that time did not realize the scale of what was happening. Today, we are already living inside an emerging climate catastrophe. For many decades to come we will be hearing ever more troubling climate news. But we cannot fix anything quickly, we can only fight to prevent the most negative scenarios.

In the next long-reads, we will look at what we can expect from new technologies in the 21st century and why we need to change the focus from the challenges of climate change to the more serious challenge caused by the ongoing Great Transition underlying both the climate and much more besides.

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