1. A big picture
Over the past 150 years, human activities have increased the Earth's average temperature by approximately 1.2°C. This is a significant rise, especially when considering that the last ice age was only 6 to 8 degrees colder than current conditions—and that change occurred over millennia. Feedback mechanisms in the Earth's climate system, such as the release of methane from melting permafrost, could create a tipping point. If global temperatures rise by an additional 0.3°C, these feedback loops could trigger self-accelerating warming.
The consequences of a warmer Earth extend far beyond merely hotter days. The changing climate amplifies extreme weather events like hurricanes, fuels devastating wildfires, and exacerbates drought conditions. These environmental changes pose severe risks to food and water supplies, creating challenges that could exceed our current capacity to adapt. Therefore, the 1.2°C of warming already observed is a critical concern that demands immediate action.
2. Why is earth warming?
The primary culprit is greenhouse gases, which trap heat radiating from the Earth's surface. Carbon dioxide (CO2) accounts for approximately 80% of all greenhouse gas emissions, effectively acting as a thermal blanket that keeps heat — or more scientifically, infrared radiation — from escaping into space.
So where does this CO2 come from? Major sources include electricity generation and industrial processes. To understand the impact, let's delve into how electricity is produced and how goods are manufactured. These activities often rely on burning fossil fuels, which releases CO2, thereby contributing to the Earth's warming.
3. How is electricity generated?
At the heart of electricity generation is a fascinating principle: a rotating magnet induces an electric current. To make the magnet spin, various methods are employed, but most commonly, it's achieved by burning fossil fuels like coal or natural gas to generate heat. Why do we need heat to spin the magnet?
The heat serves a purpose; it converts water into steam. Think of this steam as a forceful wind capable of pushing the blades of a turbine, causing it to spin. Within this spinning turbine is a rotating magnet encircled by stationary coils of wire. The rotation of the magnet creates a moving magnetic field around the coils.
This is the pivotal moment in electricity generation. According to the principles of physics, a moving magnetic field induces an electric current in a coil of wire. And that's exactly what happens here. The induced current in the coils is then directed through electrical circuits to power various applications.
Approximately 60% of the electricity we consume is generated from carbon-emitting fuel sources like coal and natural gas. When these fuels are burned to produce heat, CO2 is also released as a byproduct. However, there are alternative methods of electricity generation that are carbon-neutral. These include nuclear fission, wind turbines, and solar panels. Interestingly, solar panels operate on a different principle: they directly convert sunlight into electricity through the photovoltaic effect, bypassing the need for rotating magnets entirely.
Electricity consumption is set to increase; a decrease is unlikely given modern demands. Therefore, altering the energy source mix is imperative for a sustainable future.
4. How is manufacturing done?
Making things emit CO2 about as much as generating electricity does. In the realm of manufacturing, the production process often relies on energy-intensive operations. Whether it's the smelting of metals, the molding of plastics, or the assembly of electronics, these processes usually require a considerable amount of heat and mechanical energy.
For example, smelting metals, such as iron and aluminum, involves melting ore at high temperatures to separate the metal from impurities. Plastic molding often uses heat to melt resin into specific shapes. Electronics assembly may involve soldering, where heat is used to join metal parts. In these processes, heat is often generated by burning fossil fuels like coal in large industrial furnaces or boilers.
When these fuels burn, they undergo a chemical reaction that releases energy in the form of heat, but also emits carbon dioxide (CO2) as a byproduct.
5. What should we do?
As an individual, I concentrate on two main strategies. First, I dedicate time to understanding the climate crisis by reading books, taking courses, and studying basic principles in physics and geoscience. Second, I disseminate this knowledge through effective channels to maximize impact.
I think you can do the same things I'm doing, or maybe even more if you have more resources or know more people. If that happens, I'd consider my efforts well-spent.
Was it a good read? I recommend that you dive a little deeper and think about the technologies discussed in this story. There are many things I didn't explain why.
For example, electromagnetic induction isn't just "magnets can make electricity." It's one of the most foundational principles in physics, explaining many of the phenomena we encounter every day.
Carbon dioxide is more effective at absorbing and emitting infrared radiation compared to nitrogen or oxygen, due to its molecular structure and vibrational modes.
We can infer past Earth temperatures through the levels of Oxygen-18, an isotope of oxygen distinguished by having two extra neutrons compared to its most common form.
Gaining more knowledge in science, engineering, and technology can significantly improve your decision-making for the better.
Until next time,