The History and Science of Global Warming

The story of global warming is about energy. Classical physics holds its interest in an object’s momentum which is the product of its mass and velocity, i.e., \(\mathbf{p} = m \mathbf{v}\). This core quantity in classical physics essentially sets the end goal of any endeavor within the framework: to find the velocity and mass. The velocity and the differential equation that describes how it would change over time are so integral to Newtonian physics, scientists had thought physics is all about changes. But, as time progressed, they’ve come to realize there is something called energy that does not change, a physical phenomenon we now call the ‘conservation of energy’. Energy merely transforms during a motion but is never further created nor destroyed. The forms of energy include the solar energy, thermal energy, and the electrical energy. If the electrical energy is a form of energy, the conservation of energy tells us that some other form of energy would have vanished as soon as we ‘create’ electricity. The world of energy is governed by the Law of Equivalent Exchange. Fullmetal Alchemist?

The way to create electricity is extremely simple, surprisingly: electromagnetic induction or Faraday’s law. An action as simple as moving a magnet around an electric circuit will create electricity. It works the other way around as well: move the circuit around a magnet. If you happen to visit a power plant regardless of which type it is, they’re all relying on this simple phenomenon that a British scientist, Faraday, discovered around two hundred years ago. Instead of moving a magnet since it’s made of heavy metals like manganese and cobalt, power plants have turbines that move thick electric circuits connected at the end surrounded by stationary magnets.

with the friendly permission of Siemens Germany by Christian Kuhna (CC BY-SA 3.0)

A steam turbine rotor being assembled in a Siemens factory in Germany

All that is left is to spin the turbines. If you remember the trembling lid of an overheated pot, that is what power plants use to propel the turbines. How a power plant boils water is what categorizes it into either a fossil-fuel power plant, geothermal power plant, or a nuclear power plant. To provide enough electricity to power an entire city, or even a country, power stations need to boil a massive amount of water. To this date, fossil-fuel power plants are the most cost-efficient. This results in the burning of excessive fossil fuel, which then leads to massive emission of greenhouse gases.

From Constructive Skepticism To Collective Awareness#

It was first suggested around the early twenty-first century that there might be some sort of global warming at play. At first, not every scientist was sold. Many were justifiably skeptical that human activities, as influential as they may be, couldn’t possibly cause a change in the climate on the Earth’s scale. Unlike the prevalent belief, science does not provide clear-cut answers but rather attempts to quantify how likely a phenomenon is. Uncertainty is probably a key element in any scientific endeavor. Therefore, to the surprise of many, climatologists don’t claim global warming with 100% certitude. The scientific community at the time were still skeptical but alert.

The constructive skepticism led to the establishment of a body under the United Nations to investigate the climate change issue in the late 1980s. The initial report by the The Intergovernmental Panel on Climate Change (IPCC) that suggested the existence of global warming came out in the early 1990s. Up until the second climate report which was written five years after the first, the tone was rather cautious in that they left room for error despite admitting a change in the global climate. There have been five reports since, and the degrees of belief that the climate change is man-made have increased with each report. This is not to fearmonger the general public but rather because there is overwhelmingly abundant evidence that it is, in fact, anthropogenic.

A common misconception about global warming people have is that the region in which we live in is sometimes too cold to believe that the Earth is warming up. But it mustn’t be forgotten that global warming is at a global level. One specific region can experience a sudden drop in temperature at a given time but that doesn’t disprove global warming.

Furthermore, the dialogue about global warming discusses a temperature rise of 1°C or 2°C, which is probably one of the main reasons a large group of people doesn’t take global warming seriously enough. My room temperature fluctuates more than that every day. How could a 1°C increase spell the end of the world? According to NASA, the average global temperature has risen around 1.1°C since the Industrial Revolution. It doesn’t sound alarming enough to raise awareness, does it? However, remind yourself that the increase in the temperature translates back to thermal energy. With the mass of the the Earth’s atmosphere and the 1.1°C increase in the global temperature, physicists can calculate the required energy. Speaking in terms of the atomic bomb dropped in Hiroshima during World War 2, the thermal energy that has brought about the 1.1°C rise amounts to four atomic bombs every second since the Industrial Revolution.

Human activities in and of themselves do not create more heat and cause the rise in the temperature. It is more accurate to say that the activities rather prevent the solar energy from exiting the Earth which is then translated into heat. Usually, gases like carbon dioxide absorb the sunlight and get heated up. The Paris Agreement in 2016 aims to keep the global temperature below 2°C above the pre-industrial levels by putting a cap on carbon emission. The funny part is all that talk about 2°C or 1.5°C is fairly arbitrary. Scientists do not have a solid answer regarding what could happen if the temperature kept rising because the Earth is such a complex system. They hypothesize, however, that there exists a tipping point beyond which the Earth’s temperature will increase itself regardless of human efforts. We are essentially gambling on where the tipping point might be, and we’ve betted on 2°C in the Paris Agreement. Past the tipping point, wherever it might be, even if we stop all activities, including riding our cars and creating electricity in power stations, the rise will supposedly continue beyond control. We will enter into a realm we’ve never known before. There is, however, one thing we do know for sure. Every time there was an incorrigible change in the climate, it was inevitably followed by a mass extinction.

Difficulties#

The global warming happens at a macroscopic scale which requires a relatively long time from a human perspective. The goals laid out in the Paris Agreement talk about 2100. As parochial as it might seem, the consequences feel far away enough for ordinary people to discount the risk. Daily concerns will always trump longterm ones, and people will not budge to inconvenience themselves unless they have to. The problem is, it will be too late if we have to.

Renewable Energy?#

To understand what can and cannot be used as renewable energy, it is important to know what happens when we burn fossil fuels. The most integral part of this so-called ‘combustion’ is carbon. But carbon is included in this process not because it can create heat by itself but rather because it forms a ‘skeleton’ for other elements. The flesh around that skeleton consists of hydrogen. When hydrogen combines with oxygen, heat is emitted which can then be used to create electricity. Thus, what we really need from the fossil fuels is the hydrogen. If we can directly use hydrogen with no carbon involved, the only byproduct will be water (H2O).

The difficulty in using hydrogen directly lies within the fact that hydrogen does not exist on its own. Hydrogen is the most abundant element in the entire universe but, ironically, there is no hydrogen around us. Hydrogen, by default, combines with other elements, forming compounds like water, ammonia, methane, and sugar. The fact that hydrogen never stands alone implies that the hydrogen atoms must be detached from a compound. ‘Electrosis’ applies electric charge to water that breaks the chemical bond between the hydrogen and oxygen atoms. However, this starts from already having the electricity so we’re going in circles. An alternative is to chemically detach the hydrogen atoms from water through catalysts like platinum or iridium but these are rare and expensive. Iridium, in particular, is one of the rare-earth elements. The acquisition of the hydrogen atoms is already a predicament.

For hydrogen to be used at a commercial level, the storage thereof must be solved in advance for it to be transported and kept in bulk. But the gaseous form of hydrogen requires massive tanks, or it should be compressed at the risk of explosion. Another option is to liquefy the hydrogen but that requires -253°C (-423°F). None of the options is viable, physically or financially.

What next?#

  • Nuclear power plant doesn’t, in fact, create greenhouse gases. It is potentially a great solution as long as the danger of explosion and radioactive leaks can be minimized.
  • The renewable energy sources like wind, geothermal energy, and solar energy are limited by the availability and their vulnerability to changing weather conditions. The percentages of those sources are quite low as of now due to these restrictions. Despite these drawbacks, they’re free of charge. This should eventually be the way to go.
  • The heat used in power plants is usually discarded afterward. One can measure the ‘efficiency’ of different types of power plants. By reusing the hot water vapor to heat up a nearby city, the efficiency can be increased from 45% to near 80%. However, this doesn’t completely remove carbon emission unless an environmentally-friendly energy source is used, and is limited by the physical distance between the power station and the city in which the leftover heat is used.

There is a very simple oft-overlooked solution to the climate crisis: use less electricity and drive less. Of course, scientists will continue to investigate new ways to create green energy, and at some point we will be able to generate carbon-free energy. Nevertheless, we can’t bask in our complacency waiting for the Messiah to deliver us from evil. A slight change in our attitude will let politicians implement potentially inconvenient but necessary policies to address the climate problem without the fear of political repercussion. A collective willingness to tolerate inconvience enabled by our politics is a small price we pay to save our planet. Remember the Law of Equivalent Exchange.

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