Controlling global warming

Nov. 17, 2020
Transitioning to a 'green future' can become the motor of global recovery

In past articles I've covered the controls needed to transfer from the present fossil-fuel-based energy economy to a future solar-hydrogen-based energy economy. This green energy economy system will have a collector-electrolyzer-compressor (CEC) at the source end and a hydrogen storage-fuel cell (HFC) combination package at the user end. In past articles, I've also described the controls of the reversible fuel cell (RFC), the versatile device that generates hydrogen for storage when solar energy is in excess and reverses to generate electricity from hydrogen when solar energy is insufficient.

I've argued that our stone-age ancestors didn't switch to using bronze because they ran out of stones; they switched because it was better. So should we switch to green energy and leave fossils where they are. In past articles, I've also shown that robotization and artificial intelligence can provide the workforce needed to accomplish this transformation, and that present goals that hope emissions will peak by 2025, that they'll drop some 45% by 2030 and 100% by 2050 are overly optimistic in an age when there are leaders who question the very existence of global warming (GW).

In this article, I'll show that the GW process is self-stabilizing, and that it contains many positive feedback processes and tipping points. Unfortunately, many future-prediction models disregard these positive feedback processes and, as such, are highly inaccurate. I'll end with some comments on the economy of the conversion.

Positive feedback and tipping points

GW is a multivariable, heat-transfer process. It consists of a warm object (the Earth) rotating in a cold environment (outer space). The Earth has to be heated to maintain its temperature. It has two heat sources, one is outside (the Sun), the other (a much smaller one) inside, which I will neglect in this analysis. The heat balance will be stable if the following three variables are constant: 1) the amount of solar energy received, 2) the insulation of the planet, and 3) the reflectivity of the Earth's surface. Let us look at all three.

First, the amount of solar radiation received by the Earth varies because the Earth orbits the Sun at an angle. The solar energy reaching different parts of our planet isn't constant, but varies during the course of a year. This is the reason we have different seasons and why the seasons are opposite in the Northern and Southern hemispheres. There are three reasons for the variation: eccentricity of the Earth's orbit, which varies the planet's distance to the Sun (and triggers ice ages every 100,000 to 200,000 years); the orientation of the Earth's axis, which cycles off-center every 26,000 years; and the tilt-angle of the Earth's axis, with a cycle period of 41,000 years. It's obvious that none of these variables can be responsible for GW because they're all several magnitudes slower than the fast-increasing GW.

Figure 1: According to NASA ice core analysis, the carbon dioxide concentration in our atmosphere hasn't exceeded 300 ppmv in the past million years. Today, it is 415 ppmv and rising. Source: NASA, https://climate.nasa.gov/evidence/ Credit: D. Luthi et al., 2008; D. M. Etheridge et al., 2010; Vostok ice core data/J. R. Petit et al.; NOAA Mauna Loa CO2 record.

Second, life on Earth is made possible by the existence of our atmosphere, which, among other functions, insulates us from the cold of outer space. This insulation also keeps the "back side" of the Earth (the side not facing the Sun) warm. This insulation is facilitated by greenhouse gases, which reflect radiated heat back to Earth. The concentration of these carbon-dioxide-equivalent gases did not rise above 300 ppmv during the last 1 million years (Figure 1). Today it's 415 ppmv and rising. So, this “insulation" is now a variable, owing to the accumulation of our emissions during the Industrial Age. Today, every human being emits 3.6 kg of carbon daily. At the beginning of the industrial age, the total carbon in the atmosphere was 600 gigatons (GTC), and today it's 880 GTC and growing.

Third, the albedo, or reflectivity, of Earth's surface is about 0.3 and is dropping. In other words 30% of the solar radiation received is reflected back into outer space. The albedo varies with the nature of the surface. For example fresh snow reflects 90% (albedo = 0.9) of incoming radiation, while water reflects less than 10% and absorbs the rest. As GW melts the polar ice caps, Earth’s surface is replaced by water and permafrost, so its albedo drops drastically, even as the heat absorption of the surface rises. Therefore, the changing reflectivity of the earth's surface is not only a variable, but a self-accelerating one. In the process control profession, we call this phenomenon "positive feedback."

Secondary interactions

Two of the three main components of the Earth's heat-balance are variables (carbon dioxide in the air and albedo of the surface). Their variations can be influenced by positive and negative feedback sub-processes. Let's review the positive ones.

When snow/ice cover melts over land and the permafrost is exposed to GW, this material—that was frozen for several millennia—also melts and releases immense amounts of carbon. The total carbon dioxide content of the permafrost is estimated to be twice as much as that in the atmosphere. In addition, it contains large amounts of methane, which is a greenhouse gas 26 times more powerful than carbon dioxide.

The oceans are by far the largest carbon reservoirs on the planet. When GW increases, the oceans release immense amounts of carbon dioxide (degassing) because the rise of water temperature lowers its solubility. At the same time, more carbon dioxide in the air also increases acidification (lowers the pH) and increases the solubility of carbon dioxide. Acidification already has killed 30% of the coral reefs (the rain forests of the oceans). The combined effect of the oceans isn't well understood, and the various future models disagree about it or disregard it.

A self-stabilizing process

The present extent of GW (anomaly), which is about 1.1°C, has already exceeded all temperatures that occurred during the past 100,000 years. Further, during the last 1 million years, this anomaly has never exceeded 3 °C. On the other hand, during a presentation of its 2020 report to the U.N., World Meteorological Organization Secretary-General Petteri Taalas stated we're now on a path to 5.4 °F (3 °C).

The “personality” of the GW process is a self-stabilizing one because the energy that the Earth radiates back into space diminishes as the plane's temperature rises. This is because the Earth loses more and more heat to outer space as its temperature rises, and when this increased cooling offsets the heat gain caused by the greenhouse effect, the global temperature stops increasing—the heat-balance of the planet is reestablished.

This sounds like a happy conclusion, as it suggests that all we need to do is wait and the GW will stop rising on its own. Well, yes it will eventually stop rising, but that will be too late for human civilization. If GW rises to just 3 °C, 1 million plant and animal species will be decimated and a large part of the Earth will no longer be able to support human life. In addition to disease and starvation, it will trigger a Biblical scale migration that could destroy human civilization.

The UN’s Intergovernmental Panel on Climate Change estimates that exceeding the GW limit of just 2°C will cost some $54 trillion in damages. This sum is double U.S. GDP. The transition to a “green future” will also cost immense amounts of money, but it will also create an immense numbers of jobs. This transition is already happening in Utah where Mitsubishi is replacing a coal plant with a solar-hydrogen one.

So, we have reached a fork in the road of human evolution. We must take the one with the sign “Trust Science,” because the other reads: "Dead End." We must not only leave the fossil fuels where they are, but must also start preparing our profession, the instrumentation and control profession, to automate all these new systems, plus we must start preparing our coal workers to learn how to maintain wind turbines and our oil workers how to install solar panels. This conversion will be a new Marshall Plan and will become the engine of economic growth, a motor of global recovery, while we complete the transition to a safe, free and inexhaustible energy future by mid-century.

About the author: Béla Lipták
About the Author

Béla Lipták | Columnist and Control Consultant

Béla Lipták is an automation and safety consultant and editor of the Instrument and Automation Engineers’ Handbook (IAEH).